The effects of subject's reading achievement level in a recognition memory task
by Anne Thompson-Gibbs
A thesis submitted in partial fulfillment of the requirements for the degree of Master of Science in
Psychology
Montana State University
© Copyright by Anne Thompson-Gibbs (1982)
Abstract:
Studies of recognition memory usually examine the effects of variables related to the stimulus
materials, one of the most common being the meaningful ness of brief letter strings. The subject in a
recognition study may use meaningfulness as a cue in the decision process. Conceivably the subject's
reading achievement level may directly affect letter string recognition due to differences in accessing
letter string codes during the recognition process. A signal detection paradigm was used to obtain
measures of performance for the two reading achievement groups in a recognition task varying the
meaningful ness of CVC trigrams. Non-parametric measures were employed to evaluate differences in
sensitivity and response bias. While there were no differences in the levels of sensitivity as a function
of the subject variable, there were significant differences in response bias, suggesting that the less
capable reader does not process letter strings in the same manner as the skilled reader. THE EFFECTS OF SUBJECT'S READING ACHIEVEMENT LEVEL
IN A RECOGNITION MEMORY TASK
by
Anne Thompson-Gibbs
A t h e s i s submitted in p a r t i a l f u l f i l l m e n t
o f the requirements f o r the degree
of
Master o f Sc ie nc e
in
Psychology
■
■ MONTANA STATE UNIVERSITY
Bozeman, Montana
December 1982
MAnN U B .
T3W 5
£c>p'£
APPROVAL
o f a t h e s i s submitted by
Anne Thompson-Gibbs
This t h e s i s has been read by each member o f the t h e s i s committee
and has been found to be s a t i s f a c t o r y regarding c o n t e n t , English
usage, format, c i t a t i o n s , b i b l i o g r a p h i c s t y l e , and c o n s i s t e n c y , and
i s ready f o r submission to the C o ll e ge o f Graduate S t u d i e s .
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Date
Approved f o r the Major Department
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Approved f o r the Co lle g e o f Graduate S t u d i es
Date
Graduate Dean
iii
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iv
. TABLE OF CONTENTS
Page
ABSTRACT.................................................................' ........................................................
INTRODUCTION ............................................................ , .
..........................................
vti
I
METHOD............................................................................................
S u b j e c t s .....................................................................................................
Stimulus M a t er ia ls ...........................................................
Apparatus..............................................................................
Procedure. . ..............................................................................
8
8
RESULTS AND DISCUSSION.........................................................................................
Measures o f S e n s i t i v i t y and Response B i a s ................................................
Area Under th e ROC Curve - P /A) ....................................................... • •
Chi Square Values as a Measure^of Response B ia s . . . . . . .
Mean Rating Category V a l u e s ................................................................................
Summary and C o nc lu sio n s. . . '....................................................... .... • •
15
15
18
23
26
27
REFERENCES.......................................................................................................
APPENDICES
A. I n s t r u c t i o n s t o S u b j e c t s ............................................................................
B. Post Experimental Q u es t io n n a ir e . .........................................................
37
41
43
V
LIST OF TABLES
■ Page
1.
Mean Meaningful ness Value f o r Each CVC Condition by Tray . . .
10
2.
A n a l y s i s o f Variance f o r Area under the ROC Curve
As a Measure o f S e n s i t i v i t y . . ....................... ....
19
3.
A n a l y s is o f Variance f o r Chi Square (2x6)
As a Measure o f Response. B i a s .................................................................
4.
A n a l y s is o f Variance f o r Mean Rating Category Values
As a Measure o f S e n s i t i v i t y and Response B i a s ......................
•
29
vi
LIST OF FIGURES
Page
1.
ROC Curves f o r Meaningful ne s s C o n d i t i o n s ..............................................
20
2.
Sample Frequency Data as Organized f o r Computation
o f Chi-Square Measure o f Response B i a s ..........................................
24
Mean Response C a te g o ri e s f o r Old and New CVC Conditions . . .
28
3.
vii
ABSTRACT.
S t u d i e s o f r e c o g n i t i o n memory u s u a l l y examine the e f f e c t s o f
v a r i a b l e s r e l a t e d to the st im u lu s m a t e r i a l s , one o f the most common
being the meaningful n ess o f b r i e f l e t t e r s t r i n g s . The s u b j e c t in a
r e c o g n i t i o n study may use meaningful n ess as a cue in the d e c i s i o n
p r o c e s s . Conceivably the s u b j e c t ' s reading achievement l e v e l may
d i r e c t l y a f f e c t l e t t e r s t r i n g r e c o g n i t i o n due t o d i f f e r e n c e s in
a c c e s s i n g l e t t e r s t r i n g codes during the r e c o g n i t i o n p r o c e s s . A
s ig n a l d e t e c t i o n paradigm was used t o ob ta in measures o f performance
f o r the two reading achievement-groups in a r e c o g n i t i o n t a s k varying
the meaningful ne s s o f CVC tr ig r a m s. Non-parametric measures were
employed t o e v a l u a t e d i f f e r e n c e s in s e n s i t i v i t y and response b i a s .
While t h er e were no d i f f e r e n c e s in the l e v e l s o f s e n s i t i v i t y as a
f u n c t io n o f th e s u b j e c t v a r i a b l e , t h e r e were s i g n i f i c a n t d i f f e r e n c e s
in resoo ns e b i a s , s u g g e s t i n g t h a t the l e s s capable reader does not
pr oc es s l e t t e r s t r i n g s in t h e same manner as the s k i l l e d reade r.
I
INTRODUCTION
S t u d i es o f r e c o g n i t i o n memory u s u a l l y take i n t o c o n s i d e r a t i o n
the e f f e c t s o f v a r i a b l e s r e l a t e d o n ly t o the sti mu lus m a t e r i a l s .
When
th e st im u lu s m a t e r i a l s c o n s i s t o f l e t t e r s t r i n g s or words, t h e s e
v a r i a b l e s o f t e n i n c l u d e approximation to th e English language,
meaningful n e s s , p r o n o u n c e a b i l i t y , and f a m i l i a r i t y .
Underwood and
Schulz (1960) s u g g es te d t h a t t h er e are a number o f r e l a t i o n s h i p s
between meaningful n e s s , p r o n o u n c e a b i l i t y , and f a m i l i a r i t y , and t h a t
one or a l l o f t h e s e may play a part in the r e c o g n i t i o n o f l e t t e r
s t r i n g s and words.
The s u b j e c t in a r e c o g n i t i o n study would use t h e s e
f a c t o r s as cues a i d i n g the d e c i s i o n p r o c e s s .
P e t e r s o n , P e t e r s o n , and M i l l e r (1961) found p o s i t i v e
r e l a t i o n s h i p s between meaningful n es s and s h o r t term memory with the
s i n g l e p r e s e n t a t i o n o f trigrams and t h r e e l e t t e r words.
Keppel and
Underwood (1967) v a ri ed response meaningful n ess in a paired a s s o c i a t e
paradigm and found a p o s i t i v e r e l a t i o n s h i p between meaningful ness and
s h o r t term memory in a r e c o g n i t i o n memory t a s k .
Raser (1970) s t u d i e d the e f f e c t s o f meaningful n e s s u t i l i z i n g a
paired a s s o c i a t e paradigm a ll o w i n g f o r s ep ar a t io n o f both the stimulus
and response meaningful n e s s .
Using t h e four p o s s i b l e combinations o f
high and low meaningful n ess s t i m u l i , as def ine d by Noble ( 1 9 6 1 ) , he
^
'
found t h a t mean ingfulness was an e f f e c t i v e v a r i a b l e in r e c o g n i t i o n
.
2
performance.
Raser ,indicated t h a t r e c o g n i t i o n was more l i k e l y when
both members o f a given p a i r were high in meaningful n e s s .
In an unpublished s t u d y , Thompson-Gibbs (1972) u t i l i z e d a sig n a l
d e t e c t i o n paradigm, p r e s e n t in g o l d and new CVC trigrams s e r i a l l y and
s e q u e n t i a l l y , varying meaningful n ess a c r o s s four c o n d i t i o n s .
Trials
where both o l d and new CVCs were high in meaningful n ess y i e l d e d the
b e s t r e c o g n i t i o n performance.
While i t i s w el l e s t a b l i s h e d t h a t meaningful ne s s provides
e f f e c t i v e cues t o the s u b j e c t in a r e c o g n i t i o n s t u d y , s u b j e c t s '
u t i l i z a t i o n o f t h e cues may be d i r e c t l y a f f e c t e d by:a s u b j e c t v a r i a b l e
not g e n e r a l l y c o n s i d e r e d .
Wallach (1963) approached t h e problem o f
s u b j e c t v a r i a b l e s in h i s study on th e r e l a t i o n s h i p o f s p e l l i n g
achievement t o the p er ce pt io n o f l e t t e r s t r i n g s .
He found p o s i t i v e
r e l a t i o n s h i p s between high l e v e l s o f s p e l l i n g achievement and the
recognition o f l e t t e r s t r in g s .
S p e l l i n g and reading achievement are
d i r e c t l y r e l a t e d t o one another ( J a s t a k , B i j o u , and J a s t a k , 1 9 6 5 ) , as
s p e l l i n g i s more or l e s s t h e r e v e r s e o f re a d i n g , t r a n s l a t i n g sound i n t o
graphic symbols.
S u b j e c t s ' a b i l i t y t o re c o g n i z e English words out o f
c o n t e x t , t h e n , may be a p o t e n t i a l l y confounding s u b j e c t v a r i a b l e th a t
should be co n s id er ed in r e c o g n i t i o n memory s t u d i e s .
This s k i l l ^
g e n e r a l l y d ef in ed as s k i l l e d r e c o g n i t i o n r e a d in g , or t h e a b i l i t y to
read in d iv i d u a l words out o f normal s e n t e n c e s t r u c t u r e , combines
s e v e r a l s u b s k i l l s or components t h a t may be d i r e c t l y r e l a t e d to
r e c o g n i t i o n memory performance.
These s u b s k i l l s are d i s c u s s e d by
Eleanor Gibson in her 1969 a n a l y s i s o f reading s k i l l s .
3
The f i r s t o f t h e s e i s the a c q u i s i t i o n o f lan guage, not only
comprehending i t s meaning, but p e r c e i v i n g i t s vari ous segments and
ord ers o f combination.
The second s k i l l
i s v is u a l d i s c r i m i n a t i o n o f
the va ri o us l e t t e r s , n o t in g the c o n t r a s t s and s i m i l a r i t i e s in t h e i r
form.
Both t h e s e s k i l l s are o r i g i n a l l y developed during th e preschool
y e a r s and reach maturation during the e a r l y school y e a r s .
Neither
needs t o be co n sid er ed in a word r e c o g n i t i o n ta sk u n l e s s the s u b j e c t
pop ulat ion i s known t o have d e f e c t s in v i s u a l p erc ep ti o n or i s
co n sid er ed l e a r n in g d i s a b l e d .
The decoding o f w r i t t e n language i s the t h i r d s k i l l ,
At t h i s
reading l e v e l the s u b j e c t reads out in s i l e n t v e r b a l i z a t i o n u n i t s what
i s d i r e c t e d by the w r i t t e n u n i t s .
This may be an important s k i l l in
the r e c o g n i t i o n o f l e t t e r s t r i n g s and words, e s p e c i a l l y i f the
v e r b a l i z a t i o n u n it i s not a word, but r a t h e r , a s t r i n g o f l e t t e r s .
If
the l e t t e r s t r i n g can be coded as m e a n in g f u l, i . e . , one t h a t can be
a s s o c i a t e d with known words or w o r d - li k e p a t t e r n s , t h e s u b j e c t i s more
l i k e l y t o r e c o g n i z e t h a t sequence when i t i s presented t o him as a
r e c o g n i t i o n s t im u lu s .
Jackson (1980) s u g g e s t s t h a t the b e t t e r reader i s more e f f i c i e n t
in th e p r o c e s s e s o f a c c e s s i n g l e t t e r c o d e s , and t h a t t h e un fa m il ia r or
new item w i l l be proces se d more q u i c k l y by the b e t t e r reade r.
A unique
ite m , i . e . , o n e t h a t i s an u n f a m i li a r l e t t e r p a t t e r n , may be processed
s e r i a l l y by the l e s s s k i l l e d readers due t o t h e i r decreased
a u t om at iz a tio n o f r e c o g n i t i o n s k i l l s .
This i s supported by He aly's
(1981) d i s c u s s i o n o f th e r u l e s readers use to process reading u n i t s .
She s u g g e s t s t h a t a l e t t e r s t r i n g i s proces se d as a u n i t when i t i s
4
normally co n ta in ed in a fre q u en t word, but t h a t when t h e l e t t e r s t r i n g
i s u n f a m i l i a r , i t i s proces se d in s i n g l e l e t t e r u n i t s .
Gibson's four th s u b s k i l l r e l a t e d t o the r e c o g n i t i o n o f new words
i s the a b i l i t y t o read in high er order u n i t s . . . reading in chunks,
u t i l i z i n g a l l o f the s t r u c t u r a l r e g u l a r i t i e s found in t h e w r i t t e n
language.
I t i s t h i s s k i l l t h a t f a c i l i t a t e s the l e a r n i n g o f new words,
a ll o w i n g the reader t o a t t a c h meaning t o t h e various combinations o f
w r i t t e n symbols.
This s k i l l
i s c o n t i n u o u s l y developed and improved
upon with p r a c t i c e , l e a d i n g to t h e d i f f e r e n c e s in performance t h a t are
measured by t e s t s o f word r e c o g n i t i o n .
S k i l l e d r e c o g n i t i o n reading as d i s c u s s e d here i s measured by one
o f the s u b t e s t s o f t h e Wide Range Achievement Te st (WRAT) d ev is ed by
J a s t a k 5 B i j o u , and Ja stak ( 1 9 6 5 ) .
During development and
s t a n d a r d i z a t i o n o f the WRAT, re se ar ch in d i c a t e d t h a t the t e s t s co re s
c o r r e l a t e h ig h ly with the verbal s c o r e s o f various o t h e r in d iv id u a l
i n t e l l i g e n c e t e s t s , and with o t h e r s t and ard iz ed t e s t s measuring
academic achievement.
With the tendency f o r r e s e a r c h e r s to use r e a d i l y a v a i l a b l e
s u b j e c t s and small groups f o r r e c o g n i t i o n s t u d i e s , perhaps the a b i l i t y
t o re c o g n i z e words out o f c o n t e x t should be con sid ere d a s u b j e c t
variable.
S u b j e ct s are o f t e n a s e l e c t group, i . e . , c o l l e g e s tu d en ts
who tend t o be a t the upper end o f the reading achievement s c a l e s f o r
the general p o p u l a t io n .
C ol le g e s t u d e n t s do, however, e x h i b i t a wide
range o f i n t e l l e c t u a l and academic s k i l l s and cannot be co ns ide red to
be a matched s u b j e c t group f o r s t u d i e s t h a t r e l y h e a v i l y on one
specific s k i l l .
The use o f a word r e c o g n i t i o n t e s t such as the WRAT
5
would a l l o w the experimenter t o s cr ee n s u b j e c t s subsequently.making
comparisons between s u b j e c t p o p u l a t io n s i d e n t i f i e d by d i f f e r e n c e s in
reading achievement l e v e l s and, by doing s o , avoid what may prove to
be a confounding v a r i a b l e in r e c o g n i t i o n s t u d i e s t h a t use l e t t e r
/
s t r i n g s as st im u lu s m a t e r i a l s .
Sin ce i t i s p o s s i b l e t h a t more s k i l l e d readers pr o ce ss l e t t e r
s t r i n g s in u n i t s as s u g g es t e d by Jackson ( 1 9 8 0 ) , Healy ( 1 9 8 1 ) , and
Gibson ( 1 9 6 9 ) , w h i le the l e s s s k i l l e d reader p r o c e s s e s l e t t e r s t r i n g s
s e q u e n t i a l l y , t h e r e may very well be d i f f e r e n c e s in performance between
t h e two. groups.
Most r e c o g n i t i o n s t u d i e s a ll o w on ly a very b r i e f time
f o r both l e a r n i n g t r i a l s and r e c o g n i t i o n t r i a l s .
The reader who cannot
proc es s a p a r t i c u l a r item as a u n i t simply does not have time to e n t e r
t h a t item i n t o the memory code as a meaningful b i t o f infor m at ion ,
In
the r e c o g n i t i o n t a s k , t h e r e f o r e , t h e r e i s l i t t l e information pres en t
in t h e memory code t h a t i s o f value t o the s u b j e c t in making the Old
or New d e c i s i o n .
This would i n c r e a s e both the s u b j e c t ' s tendency to
make er r o r s and h i s tendency t o g u e s s .
This s t u d y , t h e r e f o r e , c o n c e n t r a t e s on the e f f e c t s o f a p o s s i b l e
s u b j e c t v a r i a b l e , i . e . , th e a b i l i t y o f the s u b j e c t to r e c o g n i z e words
out o f the normal c o n t e x t as measured by the reading s u b t e s t o f . t h e
WRAT.
Using a s ig n a l d e t e c t i o n paradigm (Green and S w e t s , 1966;
Sh on tz , 1 9 6 7 ) , data t r i a l s were conducted u t i l i z i n g CVC trigrams o f
d i f f e r e n t meaningful ne s s v a lu e s in the four p o s s i b l e combinations o f
high and low meaningful n e s s .
Previous s t u d i e s o f r e c o g n i t i o n performance which inv ol v ed
varying t h e meaningful n ess o f CVC trigrams as the independent v a r i a b l e
6
(Raser, 1970, and Thompson-Gibbs, 1972) have y i e l d e d c o n s i s t e n t
p a t t e r n s o f r e c o g n i t i o n performance.
I t i s expected t h a t t h e f o l l o w i n g
p a t t e r n s would again occur .
1.
Re cognition performance in t r i a l s where both the Old and New
CVCs were high in meaningful n ess would r e f l e c t t h e h ig h e s t
degree o f s e n s i t i v i t y t o t h e va ri o us st im u lu s f e a t u r e s .
2.
Re cognition performance f o r t h o s e t r i a l s where t h e Old CVCs
were high in meaningful n ess and the New CVCs low in
meaningful n ess would r e f l e c t s e n s i t i v i t y o f a somewhat
lower l e v e l .
3.
Re cognition performance f o r t r i a l s where the Old CVCs were
low in meaningful n ess and the New CVCs high in
meaningful n ess would r e f l e c t an even lower l e v e l o f
s e n s i t i v i t y t o the f e a t u r e s o f t h e st im u lu s m a t e r i a l s .
4.
In the t r i a l s where both t h e Old and New s t im u lu s m a t e r i a ls
were low in meaningful n e s s , the r e c o g n i t i o n performance
would r e f l e c t a very low l e v e l o f s e n s i t i v i t y .
D i f f e r e n c e s in r e c o g n i t i o n performance occur not o n ly in
response t o the meaningful n ess l e v e l s o f the sti mu lus m a t e r i a l s , but
a l s o appear t o be r e l a t e d t o the c o n t r a s t e f f e c t s e v i d e n t in the two
c o n d i t i o n s where Old and New s t i m u l i are o f d i f f e r e n t v a l u e s .
The major hypotheses o f t h i s study are:
I) Previous f i n d i n g s
w i l l c on t in u e t o hold t r u e regarding r e c o g n i t i o n performance when
meaningful n ess i s v a ri ed a c r o s s c o n d i t i o n s ; and 2) s u b j e c t s in the
h i g h e s t reading achievement group w i l l d i s p l a y c o n s i s t e n t l y b e t t e r
7 .
r e c o g n i t i o n performance under a l l four st im u lu s c o n d i t i o n s .
The Low
reading achievement g r o u p .w il l d i s p l a y s i g n i f i c a n t l y lower measures
o f performance.
8
METHOD
S u bj ec ts
Eighty s u b j e c t s were s e l e c t e d from an o r i g i n a l pool o f 120
s t u d e n t s e n r o l l e d in psychology co u rs es a t Montana S t a t e U n i v e r s i t y .
S u b j e ct s were s e l e c t e d on the b a s i s o f t h e i r sc ore on J a s t a k 5 B i j o u 5 .
and J a s t a k ' s (1965) Wide Range Achievement T e s t .
A dm in ist rat ion o f
the WRAT was the f i r s t ta s k presen ted in the experimental s e s s i o n .
S u b j e ct s were a s s i g n e d t o two achievement groups d e s ig n a t e d as High
WRAT and Low WRAT.
The f o r t y s u b j e c t s wit h the h i g h e s t WRAT s co re s
were d e s ig n a t e d the High group, w h i l e the f o r t y s u b j e c t s wit h the
l o w e s t s c o r e s were d e s ig n a t e d as the Low group.
The o n ly experimental
requirement was t h a t s u b j e c t s had normal v is u a l a c u i t y with or wi thout
corrective lenses.
Each o f the o r i g i n a l 120 s u b j e c t s was scheduled f o r a t h i r t y
minute time b l o c k , and p a r t i c i p a t e d in the data c o l l e c t i o n t r i a l s
whether or not h e /s h e was s u bs eq u en tly a s s i g n e d to one o f t h e two
11
experimental gro u p s.
Stimulus M at er ia ls
CVC trigrams used as st im u lu s m a t e r i a l s were i d e n t i f i e d by
s e l e c t i n g 200 High and 200 Low meaningful n ess CVC trigrams from Noble's
(1961) s c a l e d l i s t s .
The CVCs were chosen t o exclude English words
and known a b b r e v i a t i o n s .
't?
9
The CVCs were prepared f o r p r e s e n t a t i o n by ty p in g th e in d iv id u a l
trigrams on a c e t a t e f i l m , then mounting th e f i l m in standard 2X2" s l i d e
mounts.
Eight t r a y s o f s l i d e s were prepared f o r the experimental task
us in g t h e four p o s s i b l e p a i r i n g s o f meaningful n e s s .
.
The four
c o n d i t i o n s were d es ig n a t ed as High-High, High-Low, Low-High, and
Low-Low.
The f i r s t v a l u e , in each c a s e , r e f e r s to t h e meaningful ness
l e v e l o f t h e Old s t i m u l u s , and the second t o the New s t i m u l u s .
Two Carousel t r a y s were assembled f o r each c o n d i t i o n ; each
cont aine d 25 Old CVCs in random o r d e r , then 25 New CVCs i n t e r s p e r s e d
randomly among re p e a t s o f the 25 Old CVCs f o r a t o t a l o f 50 stimulus
s l i d e s for the recognition task.
Each s u b j e c t was given two s e r i e s o f
r e c o g n i t i o n t r i a l s , both with the same meaningful ness c o n d i t i o n f o r a
t o t a l o f 100 t r i a l s per s u b j e c t .
Old CVCs were d e f in e d as t h o s e CVCs presented in le a r n in g
t r i a l s ; the New CVCs were t h o s e added to the l i s t o f Old CVCs and
presen ted during r e c o g n i t i o n t r i a l s .
time in any c o n d i t i o n .
No trigram was used more than one
As shown in Table I , the meaningful ness values
a s s i g n e d by Noble (1961) f o r each CVC were summed f o r Old and New CVCs
in each t r a y and mean meaningful n ess v a lu es computed f o r each
condition.
I
10
Table I
Mean Meaningful ne s s Value f o r Each CVC Condition by Tray
Tray
Condition
Mean Old
Mean New
I
2
High-High
High-High
3.41
3 .5 3
3.32
3. 49
I
2
High-Low
High-Low
3. 36
3. 29
1.27 .
1 .2 6
I
2
Low-High
Low-High
1. 27
1. 26
3.3 9
3.4 2
I
2
Low-Low
Low-Low
1. 25
1 .2 7
1.2 7
1.2 6
Total p o s s i b l e range:
1.06 to 4.78.
One t r a y was used in the p r a c t i c e t r i a l s .
This t r a y was
assembled using 50 CVCs from the middle range o f N ob le 's s c a l e d l i s t s .
No CVC from the p r a c t i c e s e t was used in any o f the e i g h t s e t s o f
experimental m a t e r i a l s .
Apparatus
Stimulus m a t e r i a l s were presen ted on a rear p r o j e c t i o n screen
(12x15 in c h e s ) via dual Carousel p r o j e c t o r s equipped with automatic
s h u t t e r s and a timing d e v i c e known as t h e L a f a y e t t e T-2K c o n s t a n t
illum ination tachistoscope.
The f i r s t p r o j e c t p r o j e c t e d the CVC on
the scree n w h i l e t h e second provided comparable i n t e r v a l i l l u m i n a t i o n
t o the s cr ee n to minimize a ft er im a ge e f f e c t s .
The scree n was placed
a t eye l e v e l with t h e s u b j e c t s e a t e d approximately 36 in ch es from the
screen.
I
11
I l l u m i n a t i o n o f the experimental room during l e a r n i n g and
r e c o g n i t i o n t r i a l s c o n s i s t e d o f low l e v e l l i g h t i n g s u f f i c i e n t o nly to
a ll ow the experimenter t o record the data.
Procedure
The word l i s t from t h e Reading po rt io n o f the Wide Range
Achievement T e s t , Level II was ad m ini st ere d i n d i v i d u a l l y t o each o f
the 120 v o l u n t e e r s u b j e c t s .
The 40 h i g h e s t s c o r in g s u b j e c t s were
a s s i g n e d t o t h e High WRAT group; the 40 lo w e s t t o the Low WRAT group.
The s c o r e s and data t r i a l s from th e 40 s u b j e c t s in the middle range
were d is car ded and not included in any experimental a n a l y s i s .
The mean s co re on t h e Wide Range Achievement T es t f o r t h e High
WRAT group was 1 5 . 6 , with a range o f 1 3 .2 t o 1 7 . 1 , whereas the mean f o r
t h e Low WRAT group was 1 1 .2 with a range o f 7 . 7 to 1 2 . 2 .
The s co res
ex p re ss ed above r e p r e se n t the academic grade l e v e l o f s u b j e c t s '
r e c o g n i t i o n reading s k i l l s .
Each o f the s u b j e c t s a l s o p a r t i c i p a t e d in the r e c o g n i t i o n
port ion o f the st ud y.
To f a c i l i t a t e co un ter ba lan ci ng t h e order o f
p r e s e n t a t i o n o f st im u lu s m a t e r i a l s , a running mean was kept f o r the
WRAT s c o r e s a f t e r the f i r s t 20 s u b j e c t s had completed data t r i a l s .
S u bj ec ts t h a t f o ll o w e d were a r b i t r a r i l y a s si g n e d t o High and Low WRAT
groups depending on the s c o r e being above or below t h e then current
mean WRAT s c o r e .
A s i g n a l d e t e c t i o n paradigm was chosen as the most e f f e c t i v e way
o f o b t a i n i n g measures t h a t were s e n s i t i v e to d i f f e r e n c e s in performance
between t h e two reading achievement groups.
This paradigm, proposed
12
by Green and Swets ( 1 9 6 6 ) , i s formulated on a theo ry t h a t assumes
psychophysical judgments are based on underlying neural a c t i v i t y which
can vary in magnitude.
This a c t i v i t y can be produced by an ex ter nal
st im u lu s ( th e s i g n a l ) but can a l s o occur when no s ig n a l
s i g n a l ) i s present.
(o r a f a l s e
Gleitman (1981) prov ide s a most simple
ex p la n a t io n o f t h e s u b j e c t ' s ta s k in the d e t e c t i o n experiment:
" . . . the s u b j e c t ' s t a s k in a d e t e c t i o n experiment . . . .
He must deci de whether a given se n so r y process should be
a t t r i b u t e d to t h e s ig n a l superimposed on background n o i s e
or t o t h e background n o i s e along . . . .
On the av er a g e ,
t h e s i g n a l ( p lu s background n o i s e ) produced a pr o ce ss o f
g r e a t e r magnitude than does t h e n o i s e a l o n e , an average
value which r i s e s with in c r e a s i n g signal, s t r e n g t h . The
s u b j e c t ' s d e c i s i o n problem a r i s e s because the magnitude o f
the two s e t s o f s en sor y p r o c e s s e s f l u c t u a t e s .
. . . the
more i n t e n s e the s t i m u l u s , the l e s s l i k e l y i t i s t h a t
such con fu sio n w i l l occur.
. . . .
The b e s t they can do i s deci de t h a t t he y have a
s e n s a t i o n — t h a t t h e i r i n t e r n a l s en sor y e x p er i en ce i s
produced by a s ig n a l ra th er than by n o i s e a l o n e . And
in t h i s d e c i s i o n th ey can be wrong."
Following a t ec hn iqu e d i s c u s s e d by McNicol ( 1 9 7 2 ) , a ra t in g
s c a l e respo nse was u t i l i z e d ra t h er than the standard Yes or No answer.
!
The use o f such a s c a l e provides th e most e f f i c i e n t means o f o b t a in in g
information regarding th e s e n s i t i v i t y o f th e s u b j e c t t o ! d i f f e r e n c e s in
I
the st im u lu s m a t e r i a l s .
I
Pr io r to the p r e s e n t a t i o n o f l e a r n i n g and r e c o g n i t i o n t r i a l s ,
each s u b j e c t was handed a copy o f the i n s t r u c t i o n s .
The experimenter
went over t h e s e i n s t r u c t i o n s v e r b a l l y w h i le the s u b j e c t ! r e a d h i s / h e r
copy o f the i n s t r u c t i o n s .
A f t er the s u b j e c t had an o p p o rt u n i t y to
i
become f a m i l i a r and comfortable with th e r a t i n g s c a l e , t h e experimenter
presented th e two block s o f p r a c t i c e t r i a l s using the t r a y o f medium
13
value CVC tr ig r a m s.
The f i r s t o f t h e s e t r i a l s c o n s i s t e d o f ten CVCs
in the l e a r n i n g t r i a l and twenty in t h e r e c o g n i t i o n t r i a l .
The second
p r a c t i c e t r i a l s c o n s i s t e d o f f i f t e e n and t h i r t y CVCs, r e s p e c t i v e l y .
The s u b j e c t was encouraged to ask q u e s t i o n s regarding th e use o f the
r a t i n g s c a l e and v e r b a l l y r e i n f o r c e d f o r us in g the s c a l e e f f i c i e n t l y .
The i n s t r u c t i o n s f o r the experimental ta s k (Appendix A) were
modified from a previ ous study (Thompson-Gibbs, 1972).
The s tim u lu s c o n d i t i o n s f o r the data t r i a l s were then presented
v ia th e L a f a y e t t e p r o j e c t i o n system.
The 25 CVCs in th e l e a r n in g
t r i a l s (Old CVCs) were presen ted s e q u e n t i a l l y f o r l / 1 2 5 t h second a t
one second i n t e r v a l s .
A f t e r a f i f t e e n second i n t e r v a l between l e a r n in g
and r e c o g n i t i o n t a s k s , the f i f t y s l i d e s f o r the r e c o g n i t i o n ta s k were
presen ted f o r I / 1 25th second a t four second i n t e r v a l s .
During the
f i f t e e n second i n t e r v a l between l e a r n i n g and r e c o g n i t i o n t r i a l s the
s u b j e c t was i n s t r u c t e d t o count backwards from 100 by 3s out loud to
minimize the reh earsal o f th e Old CVCs.
The four st im u lu s c o n d i t i o n s were counterbalanced f o r order o f .
p r e s e n t a t i o n w it h in th e s tim u lu s c o n d i t i o n s as well as f o r order o f
st im u lu s c o n d i t i o n s .
This cou n ter b al a n ci ng occurred f o r both reading
groups.
During p r e s e n t a t i o n o f the r e c o g n i t i o n s t i m u l i , t h e s u b j e c t ' s
ta s k was t o respond t o each CVC shown wit h a c o n f id en ce r a t i n g o f one
through s i x , with resp on se s o f on e, two, and th ree i n d i c a t i n g an Old
CVC (one t h a t had been seen in t h e l e a r n i n g t r i a l s ) wit h co n fid en ce
l e v e l s o f Very Sure, F a i r l y Sure, and Guess ( u n s u r e ) , r e s p e c t i v e l y .
Responses o f f o u r , f i v e , and s i x i n d i c a t e d t h a t t h e CVC was New (not
14
seen in th e l e a r n i n g t r i a l s ) and with r e s p e c t i v e co n f id e n c e l e v e l s , o f
Guess, F a i r l y Sure, and Very Sure.
I t should be noted t h a t a response
o f t h r e e or f ou r i s d i f f e r e n t o n ly in terms o f the Old or New portion
o f the re sp on se .
At the end o f each experimental p r e s e n t a t i o n , each s u b j e c t was
asked to complete a po st- e x pe rim en ta l q u e s t i o n n a i r e (Appendix B).
15
RESULTS AND DISCUSSION
Measures o f S e n s i t i v i t y and Response Bias
In the pro ces s o f t a l l y i n g re sp on se s f o r each o f t h e two
.
(
st im u lu s c o n d i t i o n s (Old or New CVC) t h e raw data from each s u b j e c t
was org anized in a t w o - b y - s i x ma tri x.
Data a n a l y s i s f o ll o w e d
procedures design ed t o i l l u s t r a t e any d i f f e r e n c e s in s e n s i t i v i t y and
response b ia s a c r o s s t h e f ou r meaningful n ess c o n d i t i o n s and between
the two reading achievement groups.
Such an a n a l y s i s y i e l d s an
X
'
in-d ept h measure o f s u b j e c t performance t h a t i s not p o s s i b l e when
merely comparing c o r r e c t response r a t e .
S e n s i t i v i t y in th e p re s en t study i s de fin ed in terms o f
r e c o g n i t i o n performance.
In th e language o f the s i g n a l d e t e c t i o n
paradigm, p r e s e n t in g an Old CVC, i . e . , one t h a t occurred during
l e a r n in g t r i a l s , c o n s t i t u t e s t h e "Signal" t r i a l .
A New CVC (one t h a t
has not been p re se nt ed b e f o r e ) , c o n s t i t u t e s a "Noise" t r i a l .
The more
Old CVCs t h a t are r e c o g n i z e d , the more s e n s i t i v e t h e o b s er v er i s to
q u a l i t i e s unique t o t h e st im u lu s m a t e r i a l s .
A primary f a c t o r a f f e c t i n g
t h e s e n s i t i v i t y o f th e s u b j e c t t o CVCs varying in meaningful n ess i s
presumed t o be th e number o f a s s o c i a t i o n s t h a t can be made to the CVC
(Noble, 1 9 6 1 ) .
Also r e l a t e d to s e n s i t i v i t y i s the a b i l i t y o f the
s u b j e c t t o pro ces s a l l o f th e components o f the CVC in such a manner
t h a t th e meaningful n ess f a c t o r can o p e r a t e .
16
An a d d i t i o n a l f a c t o r was s u g g es t e d by s u b j e c t s who p a r t i c i p a t e d
in Thompson-Gibbs 1972 st ud y.
This i s a "co nt rac t e f f e c t " t h a t occurs
when Old and New CVCs d i f f e r in meaningful n ess v a l u e s .
Old CVCs t h a t
are high in meaningful ne s s w i l l appear d i f f e r e n t to the s u b j e c t when
t h ey occur along the New CVCs t h a t are low in meaningful n ess and v i c e
ve r s a .
This d i f f e r e n c e i s in the c o n t e n t o f the l e t t e r s t r i n g , s i n c e
CVCs high in meaningful n ess o f t e n f o l l o w p a t t e r n s found in common .
words, w h i l e low meaningful ne s s CVCs o f t e n appear t o have no
r e l a t i o n s h i p t o t h e l e t t e r s t r i n g s found in words.
Response b i a s , on t h e o t h e r hand, i s t h e manner in which the
s u b j e c t uses t h e r a t i n g s c a l e .
S u b j e c t s in t h e r e c o g n i t i o n study
responded us in g a s i x - p o i n t r a t i n g s c a l e .
D i f f e r e n c e s in the
.
meaningful n ess combinations o f t h e f ou r st im u lu s c o n d i t i o n s may r e s u l t
in s u b j e c t s using t h e s c a l e s d i f f e r e n t l y .
Under one experimental
c o n d i t i o n s u b j e c t s may spread out t h e i r res ponses t o Signal t r i a l s more
than t o Noise t r i a l s or v i c e v e r s a .
The mean ca t ego ry response may
s h i f t more f o r Signal t r i a l s than f o r Noise t r i a l s under c e r t a i n
experimental c o n d i t i o n s .
response b i a s .
In t h i s s t u d y , t h i s i s what i s meant by
S u bj e ct s may use the s c a l e d i f f e r e n t l y under the four
c o n d i t i o n s in a s y s t e m a t i c way.
Measurement o f such s y s t e m a t i c s h i f t s
may provide a d d i t i o n a l information on how meaningful ne s s or reading
a b i l i t y i n f l u e n c e s s u b j e c t performance in a Short-Term Memory ta sk such
as t h a t used in the p r e s e n t stud y.
I t must be po in ted out t h a t t h i s d e f i n i t i o n o f response b ias
does not r e f e r to the type o f response s e t i n d i v i d u a l s d i s p l a y when
responding on a r a t i n g s c a l e ( G u i l f o r d , 1 9 5 4 ) .
In response s e t s , a
17
tendency t o use extremes o f the s c a l e , the c e n t e r o f th e s c a l e , or a
normal d i s t r i b u t i o n o f resp onses i s determined by the s u b j e c t s
p e r s o n a l i t y or i n f l u e n c e d by the i n s t r u c t i o n s .
S e n s i t i v i t y and
response b ia s measures in t h i s study are not s e n s i t i v e t o t h i s type o f
set.
Three measures o f s e n s i t i v i t y and response b ia s were used in
an a ly zi n g t h e performance o f the two reading achievement groups.
The
measure o f s e n s i t i v i t y i s the area under the R eceiver Operating
C h a r a c t e r i s t i c (ROC) curve (P^), as d ef in ed by Green and Swets (1966)
and McNicol ( 1 9 7 2 ) .
This g e n e r a l l y a ccepted measure prov ide s an
a n a l y s i s s e n s i t i v e to t h e e f f e c t s o f meaningful n e s s , a s s o c i a t i o n v a lu es
r e l a t e d t o meaningful n e s s , and o t h e r d i s t i n c t i v e f e a t u r e s o f the CVC
trigrams used as st im u lu s m a t e r i a l s .
This measure should a l s o be
s e n s i t i v e t o any p r o c e s s i n g d i f f e r e n c e s r e l a t e d to the s u b j e c t
variable.
The measure o f response b ia s used was a m o d i f i c a t i o n o f t h e
Chi-square Goodness o f F i t T e s t .
d ef in ed e a r l i e r .
This t e s t measures response b ia s as
Shontz (1967) d i s c u s s e s t h i s measure in h i s study o f
f a c t o r s a f f e c t i n g t h e p r o c e s s in g o f s e q u e n t i a l l y presen ted form p a r t s .
He found t h i s measure t o be s e n s i t i v e t o s y s t e m a t i c changes in the use
o f the r a t i n g s c a l e as a f u n c t io n o f t h e experimental v a r i a b l e s .
A t h i r d measure, an a n a l y s i s o f the Mean Rating Category Values,
should provide information regarding both s e n s i t i v i t y and response
bias.
Shontz (1967) has e s t a b l i s h e d t h a t t h i s measure i s us efu l in
th e i n t e r p r e t a t i o n o f information regarding response b ia s data.
18
Area Under th e ROC Curve
(A)
P l o t t i n g th e p r o b a b i l i t i e s o f c o r r e c t r e c o g n i t i o n s (H i t Rates)
versu s " f a ls e" r e c o g n i t i o n s o f New st im u lu s m a t e r i a l s ( F a l s e Alarms)
from the r a t i n g s c a l e data on the u n i t square y i e l d s the Receiver
Operating C h r a c t e r i s t i c Curve d i s c u s s e d by Green and Swets (1966) and
McNicol ( 1 9 7 2 ) .
As d i s c u s s e d e a r l i e r , th e area under th e ROC curve
has become a g e n e r a l l y accepted measure o f s e n s i t i v i t y as i t i s
independent o f changes in response b i a s .
This non-parametric measure
i s u s ef ul when assumptions regarding the parametric measures o f
s e n s i t i v i t y ( d / ) and response b ia s (3) cannot be met.
P l o t s o f the
p r o b a b i l i t y data from t h i s experiment on double p r o b a b i l i t y paper
i n d i c a t e d t h a t th e assumptions f o r parametric measure had not been met.
The area measure ( P ( A ) ) has been shown to be comparable t o d/ (McNicol,
1972) and was chosen as t h e b e s t measure o f s e n s i t i v i t y .
Area v al u es were computed f o r each s u b j e c t .
These va lue s were
used as data p o i n t s f o r a two-way ANOVA f o r the area under the ROC
curve as a measure o f s e n s i t i v i t y .
• i l l u s t r a t e d in Table 2.
The two-way ANOVA Table i s
There were s i g n i f i c a n t d i f f e r e n c e s , F ( I , 72)
= 2 4 . 2 0 , !P < . 0 0 1 , in s e n s i t i v i t y as a f u n c t io n o f meaningfulness
c o n d i t i o n s i n d i c a t i n g t h a t a l l s u b j e c t groups were in some way
c og n iz a nt o f , and u s i n g , th e f e a t u r e s o f the s t im u li in reaching
decisions.
The mean area v a lu es f o r th e High WRAT group were:
High-High, .796; High-Low, .895; Low-High, .773; and Low-Low, .612.
Mean area v a lu e s f o r t h e Low WRAT group were .766; .344; .7 37 ; and
19
.737, r e s p e c tiv e ly .
There were no s i g n i f i c a n t d i f f e r e n c e s in the
s e n s i t i v i t y o f the two reading achievement groups, F ( I , 72) = 1 . 2 3 ,
£>.05.
Table 2
' A n a l y s is o f Variance f o r Area Under the ROC Curve
As a Measure o f S e n s i t i v i t y
SS
DF
MS
F
Meaningful n ess (R)
0.52 2
3
0.207
24.200***
Reading Level (B)
0.011
I
0.011
R B Interaction
0.0 1 0
3
0.003
0.39 6
Individuals
0.51 7
72
0.009
———
Total
1.26 0
79
-- -
-- -
Source
-
1.23 2
* * * S i g n i f i c a n t beyond the .001 l e v e l .
The r e l a t i v e d i f f e r e n c e s in s e n s i t i v i t y between st im u lu s
c o n d i t i o n s and t h e two reading achievement groups are i l l u s t r a t e d in
Figure I .
I t should be noted t h a t i t i s g e n e r a l l y not ap propriate to
combine raw data from i n d i v i d u a l s as i l l u s t r a t e d in Figure I as la r g e
d i f f e r e n c e s in t h e s l o p e s o f the i n d iv i d u a l curves e x i s t ( McNicol,
1972 ).
I t i s inc lu d ed here f o r i l l u s t r a t i o n purposes o n l y .
In previous s t u d i e s ( Rase r, 1970; and Thompson-Gibbs, 197 2) ,
d i s t i n c t d i f f e r e n c e s in th e pa tt er n o f r e c o g n i t i o n performance were
found when meaningfulness was v a ri ed as a sti mu lus v a r i a b l e .
Superior
r e c o g n i t i o n performance occurred when both Old and New CVCs were high
in m e an in g fu ln es s .
In t h i s s t u d y , s u b j e c t s appear t o have u t i l i z e d
20
High — High
H igh — Low
.1 .2 .3 . 4 . 5 . 6 .7 .8 .9
• 1 . 2 . 3 . 4 . 5 . 6 .7 .8 .9
Low — Low
Low— H igh
Cf
.1 . 2 . 3 . 4 . .5 . 6 . 7 .8 .9
.1 . 2 . 3 .4 .5 .6 .7 .8 .9
P
P
n
nr
H ig h WRAT
Low WRAT
Figure I
ROC Curves f o r Meaningfulness Co ndi tio ns
21
c o n t r a s t e f f e c t in a d d i t i o n t o t h e st im u lu s p r o p e r t i e s r e l a t e d to
meaningful n e s s .
Re cognition performance was s u p e r io r f o r both groups
when t h e Old CVCs were high in meaningful n ess and New CVCs were low.
I n s p e c t i o n o f t h e r e p r e s e n t a t i o n s o f the ROC curves f o r each
meaningfulness c o n d i t i o n c l e a r l y i l l u s t r a t e s the d e c l i n e o f s e n s i t i v i t y
in the f o l l o w i n g manner:
1.
S u b j e c t s Were most s e n s i t i v e t o the High-Low c o n d i t i o n .
Not o n ly were s u b j e c t s s e n s i t i v e t o the p r o p e r t i e s o f the
st im u lu s CVCs t h a t provided cues f o r l a t e r i d e n t i f i c a t i o n ,
but they seemed t o be a b le t o p ick up the c o n t r a s t in the
two l e v e l s o f meaningful n e s s .
2.
Jhe second l e v e l o f s e n s i t i v i t y was to t h e High-High
condition.
In t h i s c a s e , s u b j e c t s were s e n s i t i v e . t o the
s i m i l a r p r o p e r t i e s o f both Old and New CVCs, apparently
making comparisons with a c c e s s i b l e r e p r e s e n t a t i o n s in the
memory codes,
3.
The t h i r d l e v e l o f s e n s i t i v i t y was t o the Low-High
condition.
Under t h i s c o n d i t i o n , the Old CVCs a ll o w for.
few a s s o c i a t i o n s t h a t might a id the ob s er v er in h i s d e c i s i o n
process.
The f a c t t h a t th e New CVCs are high in
meaningful n ess and are t h e r e f o r e more wor dli ke in natu re,
probably provides a c o n t r a s t e f f e c t t h a t o f f e r s th e major
cue f o r the s u b j e c t ' s d e c i s i o n p r o c e s s ,
4.
As e x p e c t e d , the lo w e s t l e v e l o f s e n s i t i v i t y was pr es ent
in th e Low-Low c o n d i t i o n .
There i s l i t t l e information
co nt ain ed in the st im u lu s t h a t a ll o w f o r the formation o f
22
a s s o c i a t i o n s with o t h e r information nor i s t h e r e any
c o n t r a s t information a v a i l a b l e .
An i n s p e c t i o n o f Figure I s u g g e s t s t h a t t h e r e were s l i g h t
d i f f e r e n c e s in r e c o g n i t i o n performance between the two reading
achievement groups a c r o s s a l l four meaningful n ess c o n d i t i o n s .
not s t a t i s t i c a l l y s i g n i f i c a n t ,
While
F ( I , 72) = 1 . 2 3 2 , £ > . 0 5 , t h e s e
d i f f e r e n c e s in s e n s i t i v i t y may be r e l a t e d to the manner in which
s u b j e c t s pr o ce ss the st im u lu s m a t e r i a l s .
Jackson (1980) s u g g e s t s the
l e s s s k i l l e d reader i s more l i k e l y t o pr o ce ss t h e i n d iv i d u a l components
o f th e st im u lu s s e r i a l l y r a t h er than as a u n i t .
What i s not c l e a r i s
a t what l e v e l t h e degree o f reading achievement ( r e l a t e d to
ch r o n o lo g i c a l a g e , academic l e v e l , and reading a b i l i t y ) , a f f e c t s the
s e n s i t i v i t y o f the s u b j e c t t o the p r o p e r t i e s o f the s t i m u l u s .
The p o s s i b i l i t y should be co n s id er ed t h a t on ly t h o s e s u b j e c t s
who were reading a t the lower end o f t h e range were p r o c e s s i n g the
components o f t h e s t im u lu s d i f f e r e n t l y from o th er s u b j e c t s .
This would
c r e a t e t h e d i f f e r e n c e s in s e n s i t i v i t y t h a t are e v i d e n t in the p i c t o r i a l
r e p r e s e n t a t i o n o f the ROC c u r v e s .
I f o nly t h o se s u b j e c t s a t the lower
end o f t h e range o f WRAT s c o r e s are performing d i f f e r e n t i a l l y , however,
t h e r e would not be s u f f i c i e n t d i f f e r e n c e s between th e groups t o be
s ta tis tic a lly significant.
Additional s t u d i e s s e p a r a t in g s u bj ec ts, in t o
groups d i f f e r i n g in degree o f reading a b i l i t y as o u t l i n e d above would
be n e c e s s a r y t o determine where d i f f e r e n c e s in s e n s i t i v i t y , i f any,
would e x i s t .
I
23
Chi Square Values as a Measure o f Response Bias
Chi-square v al u es can be used in t e s t i n g the G o o d n e s s - o f- F it o f
a t h e o r e t i c a l curve t o an observed frequency d i s t r i b u t i o n (McNemars .
1969 ).
The Chi-square G o o d n e s s - o f- F it techn iqu e ena ble s us t o t e s t
whether t h e f r e q u e n c i e s o f an experimental d i s t r i b u t i o n depart from
t h o s e o f a t h e o r e t i c a l curve s u f f i c i e n t l y t o be regarded as chance
de p ar tu re s .
A m o d i f i c a t i o n o f t h e Chi-square G o o d n e s s - o f - F it t e s t as used
by Shontz (1967) was employed to a s s e s s the s y s t e m a t i c v a r i a t i o n s in
response b ia s as a f u n c t io n o f meaningful n ess and reading achievement
level.
S in ce th e assumptions f o r t h e parametric measure (g) could not
be met, t h i s non-parametric measure was chosen as the most s u i t a b l e
means o f e v a l u a t i n g response b ia s because i t can provide data t h a t
r e f l e c t d i f f e r e n c e s in th e use o f r a t i n g s c a l e s ac ro s s c o n d i t i o n s .
The frequency data were org anized as shown in Figure 2.
In
t h i s c a s e , t h e ord eri ng o f c o n f id e n c e l e v e l s i s re ve rs ed f o r the New
CVC p r e s e n t a t i o n s .
This new matrix p a ir s t h o se c e l l s t h a t are
e q u i v a l e n t in co n f id e n c e and acc uracy.
As a r e s u l t , as s e n s i t i v i t y
changes, t h e two frequency d i s t r i b u t i o n s can be exp ected to change
concurrently.
The shape o f the two d i s t r i b u t i o n s , when no response
b ia s i s p r e s e n t , w i l l be s i m i l a r , and the Chi-square va lu e w i l l be
small.
I f , however, t h e r e are s y s t e m a t i c s h i f t s in response bia s
a c r o s s c o n d i t i o n s , t h e Chi-square v a lu es w i l l become l a r g e r as the two
frequency d i s t r i b u t i o n s d i f f e r s y s t e m a t i c a l l y .
As t h i s measure i s
i n s e n s i t i v e t o both s e n s i t i v i t y and v a r i a t i o n b i a s , i t s e r v e s as an
independent measure o f response b i a s .
■
24
STIMULUS
OLD
NEW
27
22
6
IO
17
5
O
3
4
LU
(Z)
I
3
3
§
S)
8
3
2
4
2
(Z)
LU
QC
O
S
O
IU
CC
Figure 2
Sample Frequency Data as Organized f o r Computation
o f Chi-Square Measure o f Response Bias
Response b i a s , as d i s c u s s e d h e r e , i s not t h e type o f response
s e t c h a r a c t e r i z e d by a s u b j e c t ' s c o n s i s t e n t i d i o s y n c r a t i c use o f the
rating scale.
This measure i s s e n s i t i v e , however, t o changes in the
use o f t h e s c a l e due to ex perimental c o n d i t i o n s .
As an example, t h e r e
may be changes in th e d i s t r i b u t i o n o f re sp onses on Signal t r i a l s (Old
CVCs) w i t h o u t concomitant changes in Noise t r i a l d i s t r i b u t i o n s .
If
s e n s i t i v i t y changes a c r o s s c o n d i t i o n s but t h e use o f t h e r a t i n g s c a l e
remains c o n s t a n t f o r Signal and Noise t r i a l s , th e re sp onses w i l l be
d i s t r i b u t e d in s i m i l a r p a t t e r n s , and t h e r e s u l t a n t C hi- s qua r e Goodnesso f - F i t t e s t val ue w i l l be s m a l l.
I f resp ons e d i s t r i b u t i o n s a re
d i f f e r e n t f o r Signal and Noise c o n d i t i o n s t h e r e s u l t a n t Chi-square
value w i l l be l a r g e .
D i f f e r e n c e s in Ch i-s quare valu es a c r o s s the
25
d i f f e r e n t meaningfulness and s u b j e c t c o n d i t i o n s provide th e measure o f
respo nse b i a s .
Chi-square v al u es were c a l c u l a t e d f o r each s u b j e c t .
v a lu e s were then transformed us ing
+
Vx+1 t o
These
s t a b i l i z e t h e variance
o f d i s t r i b u t i o n o f th e Chi-square v a lu es ( Snednecor and Cochran, 1980).
The transformed v a lu e s were analyzed us in g the same ANOVA model as was
used on th e a n a l y s i s o f th e area under the ROC curve.
I t must be
poin ted out t h a t t h e s e v a lu e s are used o n ly as data p o i n t s in the ANOVA
and have no o t h e r s i g n i f i c a n c e in th e
overall analysis o f r e s u lts .
The r e s u l t s o f th e a n a l y s i s are shown in Table 3.
The
n o n s i g n i f i c a n t F ( 3 , 72) = 2 . 0 5 9 , £ > . 0 5 , i n d i c a t e s t h e r e were no
s i g n i f i c a n t changes in th e use o f the r a t i n g s c a l e as a f u n c t io n o f
meaningful n e s s .
There were, however, obvious s y s t e m a t i c d i f f e r e n c e s
in t h e use o f the r a t i n g s c a l e as a f u n c t i o n o f the s u b j e c t v a r i a b l e .
The s i g n i f i c a n t d i f f e r e n c e F ( I , 72) = 4 . 4 9 5 , P<.05 found in reading
achievement l e v e l i n d i c a t e s t h a t t h e r e were s y s t e m a t i c d i f f e r e n c e s
in the way the two reading achievement groups used the r a t i n g s c a l e .
Means f o r t h e High WRAT group were:
Low-High, 3 . 4 ; and Low-Low, 4 . 3 9 .
High-High, 3 . 5 9 ; High-Low, 3 .3 6 ;
Means f o r the.Low WRAT group were
4 . 3 4 , 4 . 4 9 , 3.64., and 4 . 6 2 , r e s p e c t i v e l y .
This measure, however,
w h i l e p ro vid ing ev i d e n c e t h a t t h e r e were d i f f e r e n c e s in response b ias
as a f u n c t io n o f reading achievement l e v e l , does not pr ov ide c l u e s to
t h e manner in which th ey d i f f e r .
These d i f f e r e n c e s are more c l e a r l y
i l l u s t r a t e d in t h e d i s c u s s i o n o f t h e Mean Rating Category Values t h a t
follows.
26
Table 3
A n a l y s is o f Variance f o r Chi Square (2x6)
as a Measure o f Response Bias
F ■
SS
DF
MS
Meaningful n ess (R) .
9. 7 8 3
3
3.261
2.059
Reading Level (B)
7.102
I
7.120
4.495*
R/B I n t e r a c t i o n
3.006
3
1.00 2
0. 6 3 3
Individuals
114.032
72
1 .584
——
Total
113.942
79
Source
-I-
*£<.05
Mean Rating Category Values
The a n a l y s i s o f t h e d i f f e r e n c e s in mean co n f id e n c e l e v e l s fo r
each c o n d it io n prov ide s an information measure f o r both response b ia s
and s e n s i t i v i t y .
By adding the response c o n d i t i o n (Old or New CVC) as
a d d i t i o n a l v a r i a b l e s in th e ANOVA, i t i s p o s s i b l e t o o b t a in an a n a l y s i s
s e n s i t i v e t o ev id e nc e t h a t mean co n f id e n c e l e v e l s are a f f e c t e d by
st im u lu s c o n d i t i o n s .
As s e n s i t i v i t y cha ng es , the mean va lue o f t h e r a t i n g categ or y
should d e c r e a se f o r t h e Old response c a t e g o r y , and c o n v e r s e l y , in c r e a s e
f o r t h e New response c a t e g o r y .
To provide a measure where the two mean
va lue s are p o s i t i v e l y r e l a t e d t o one a n o t h e r , and to avoid n e g a t iv e
v al u es in the ANOVA, t h e value o f the New mean r a t in g i s s u bt ra c te d
from seven ( £ r a t i n g c a t e g o r i e s plu s o n e ) ,
As s e n s t i v i t y to st imulus
c o n d i t i o n s cha ng es , t h e r e f o r e , t h e two means would now tend t o . s h i f t
27
upward or downward s i m u l t a n e o u s l y .
The d i f f e r e n c e between mean r a t i n g
c a t e g o r y v a lu es f o r Old and New s t i m u l i i s the index o f s e n s i t i v i t y .
D i f f e r i n g d i s t r i b u t i o n s o f response w i t h i n each o f t h e s e means across
st im u lu s c o n d i t i o n s i n d i c a t e changes in response b i a s .
Figure 3
i l l u s t r a t e s t h e s e s h i f t s in value and provides some e v id e nc e o f the
manner in which s u b j e c t groups d i f f e r .
To more c l e a r l y i l l u s t r a t e the d i f f e r e n c e s between t h e s u b j e c t
g r o u p s , t h e t ra n s f o rm at io n s o f th e Old r e s p o n s e ca t eg o r y data were not
used when p l o t t i n g the data f o r Figure 3.
The data p o i n t s r e f l e c t the
o r i g i n a l mean ca te g o r y r a t i n g v a lu e s f o r Old CVCs.
A f i n a l type a n a l y s i s o f v a ri an c e was conducted to provide
information s e n s i t i v e t o i n t e r a c t i o n s between reading achievement
groups, st im u lu s c o n d i t i o n s (mean ing fu lne ss ) and mean c o n f id en ce
r a t i n g s f o r each response c o n d i t i o n (Old or New).
The four-way ANOVA
(r(BC)D) provides a measure o f t h e d i f f e r e n c e s in s e n s i t i v i t y and
response b i a s t h a t may e x i s t between t h e two reading achievement
gr ou p s, and any i n t e r a c t i o n t h a t may be p re s en t between the mean
c o n f id en ce r a t i n g s , st im u lu s c o n d i t i o n s , and reading achievement
groups.
This measure i s redundant with the two measures p r e v i o u s l y
re p or te d.
As in d i c a t e d in Table 4 , t h i s ANOVA does provide a d d it io n a l
information regarding the d i f f e r e n c e s in performance between the two
reading achievement groups.
Of p a r t i c u l a r i n t e r e s t i s t h e s i g n i f i c a n t
i n t e r a c t i o n between meaningfulness c o n d i t i o n s and response categ or y
r a t i n g s , F ( 3 , 72) = 3 . 3 5 0 , p <. 02 , i n d i c a t i n g t h a t t h e r e were
28
HighWRAT-OIdCVC
HighWRAT- NewCVC
- Low WRAT-OId CVC
L ow W R A T -N ew CVC
H-H
H-L
L-H
L-L
MEANING FULNESS CONDITION
Figure 3
Mean Response Cat ego rie s f o r Old and New CVC Conditions
When the response was I , 2 , or 3, the s u b j e c t b e l i e v e d the CVC was Old;
when responding 4 , 5 , and 5 , the s u b j e c t b e l i e v e d the CVC was New.
29
s y s t e m a t i c d i f f e r e n c e s in the mean r a t i n g ca t eg o r y between groups as a
f u n ct io n o f mea nin gf uln es s.
Table 4
A n a l y s is o f Variance f o r Mean Rating Category Values
as a Measure o f S e n s i t i v i t y and Response Bias
Source
SS
DF
MS
26.004
72
.361
.494
I
.494
Meaningfulness (C)
14.301
3
4.767
13.119***
Response Cat. (D)
10.126
I
10.126
59.279***
rD/BC
12.299
72
.170
BC
1.65 8
3
.552
1 .531
BD
.238
I
.238
I .396
CD
1.716
3
.572
3.350**
BCD
1 .086
3
.362
2. 1 2 0
67.926
159
r/BC
Reading Level (B)
Total
—
F
—
1.370
—
—
***£<.001
**£<. 02
To s e e what i s a c t u a l l y happening, r e f e r back to Figure 3.
The
s i g n i f i c a n t d i f f e r e n c e in the use o f t h e r a t i n g s c a l e s i s a r e s u l t o f
the d i f f e r e n c e in the degree o f change a c r o s s the four s t i m u l u s .
The
pa tt ern o f the change i s roughly s i m i l a r f o r both reading achievement
groups, but i t i s e v i d e n t t h a t the low reading achievement group
ex p e r i e n c e s a much more dramatic s h i f t in co n f id en ce f o r the Low-High
30
and Low-Low c o n d i t i o n s .
I t should be noted t h a t the High WRAT group
e x h i b i t s a c o n s i s t e n t l y h igh er l e v e l o f c o n f i d e n c e .
This i s a l s o
r e f l e c t i o n o f the d i f f e r e n c e s in s e n s i t i v i t y seen in the ROC curves
o f Figure I .
The mean r a t i n g ca t eg or y v a lu es o f the High WRAT group remain
almost equal
( 1 . 9 3 , 2 .2 6 f o r Old CVCs; 2 . 0 4 , 2 . 0 8 f o r New CVCs) under
t h e High-Low and How-High c o n d i t i o n s .
e x h i b i t s a s h i f t in co n f id en ce l e v e l
The Low WRAT group, however,
( 1 . 9 6 , 2 . 7 3 f o r Old CVCs; 2 . 3 8 ,
.
2 . 9 f o r New CVCs) t h a t s u g g e s t s t h a t perhaps t h er e has been a change
in dec isi on- m ak ing s t r a t e g y or in the manner in which the sti mu lus
I
i s being p r o c e s s e d , or both.
The High WRAT group appears;.able to
u t i l i z e th e c o n t r a s t in'meaningful ness during the d e c i s i o n p r o c e s s ,
w h i l e the Low WRAT group appears not t o be u t i l i z i n g t h i s f e a t u r e .
In the Low-Low c o n d i t i o n , the High WRAT group e x h i b i t s an
extreme s h i f t toward g u e s si n g ( 2 . 5 5 Old, 3 . 8 , New CVC) and th e mean
r a t i n g c a t e g o r y v al u es f o r the two reading achievement groups becomes
n ea rl y eq u a l.
This s u g g e s t s t h a t the lack o f f e a t u r e s normally
a v a i l a b l e t o the s u b j e c t when l e t t e r s t r i n g s are o r t h o g r a p h i c a l Iy
c o r r e c t (as in the ca s e o f the High meaningful ness c o n d i t i o n ) may be
r e s p o n s i b l e f o r the s h i f t in the d e c i s i o n c r i t e r i o n .
These, s h i f t s in
mean r a t i n g c a t e g o r y v a lu e s as d i s c u s s e d here are the f e a t u r e s th a t
i l l u s t r a t e changes in both s e n s i t i v i t y and response b ia s ac ro s s
conditions.
/
The d i f f e r e n c e s i l l u s t r a t e d here r a i s e q u e s ti o n s regarding the
manner in which t h e st im u lu s m a t e r i a l s are processed in each c o n d i t i o n .
Gibson's 1969 a n a l y s i s o f reading s k i l l s s u g g e s t s t h a t the s k i l l e d
31
reader reads In terms o f h ig h er order u n i t s , or chunks, u s in g the
vari ous s t r u c t u r a l r e g u l a r i t i e s found in w r i t t e n language. D if f e r e n c e s
in performance, t h e n , may be r e l a t e d t o t h i s a b i l i t y , but cannot be
co m p le t e ly ex p la i n e d by t h e data from t h i s study.
Jackson (1980) s u g g e s t s t h a t t h e r e are two independent
components o f reading a b i l i t y .
The major component i s made up o f the
general language s k i l l s n e c e s s a r y f o r understanding language,
r e g a r d l e s s o f m o d a lit y.
The second component o f reading a b i l i t y
i n v o l v e s the p r o c e s s e s t h a t a c c e s s memory codes f o r v i s u a l
r e p r e s e n t a t i o n s a t the more a b s t r a c t l e v e l s o f a n a l y s i s .
Jackson
f u r t h e r s u g g e s t s t h a t t h e b e t t e r reader has f a s t e r a c c e s s to l e t t e r
i d e n t i t y c o d e s , a s k i l l r e l a t e d not o n l y t o reading (or l e t t e r
r e c o g n i t i o n ) , but t o the r e c o g n i t i o n o f any v is u a l p a t t er n having a
learn ed a b s t r a c t r e p r e s e n t a t i o n .
He proposes t h a t t h e r e may be two
sources o f d i f f e r e n c e between s k i l l e d and l e s s s k i l l e d , re a d e r s .
The
f i r s t i s th e p o s s i b i l i t y t h a t the s k i l l e d re a d er , a t an e a r l y ag e, has
developed the a b i l i t y to a c c e s s memory codes f o r v is u a l p a t t e r n s f a s t e r
than has t h e l e s s s k i l l e d reader a t the same ch r o n o lo g i c a l ag e.
The
a l t e r n a t i v e p o s s i b i l i t y i s t h a t t h e s k i l l e d re ad er , through p r a c t i c e ,
has f u r t h e r automatized t h e s k i l l s o f r e c o g n i t i o n f o r any meaningful
visual pattern.
In h i s study o f v i s u a l encoding speed, Jackson found
t h a t d i f f e r e n c e s in performance are r e l a t e d t o a more general
d i f f e r e n c e in the a b i l i t y to a c c e s s memory codes f o r meaningful
patterns.
This d i f f e r e n c e in a b i l i t y could produce the s y s t e m a t i c
c r i t e r i o n s h i f t s observed in t h i s stud y.
32
In rev ie w ing th e po st- e x pe ri m en ta l q u e s t i o n n a i r e s , i t was noted
t h a t both th e s k i l l e d and l e s s s k i l l e d readers observed t h e lack o f
"word-like" q u a l i t y in the low meaningful ness CVCs, but th e s k i l l e d
readers more f r e q u e n t l y commented t h a t the New high meaningful ness CVCs
were more m ean ing fu l, and t h a t they could a s s o c i a t e them wit h o th er
known words.
This may e x p l a i n the d i f f e r e n c e s in the mean r a t i n g
ca t eg o r y v al u es t h a t were e v i d e n t in th e Low-High c o n d i t i o n .
The more
s k i l l e d r e a d e r , even though unable to a s s o c i a t e the Low CVC with "word
p a t t e r n s , " was a b le in th e s h o r t time a v a i l a b l e t o pr oce ss the
inf ormation and reach a d e c i s i o n based on the c o n t r a s t e f f e c t .
The
l e s s s k i l l e d r e a d e r , ’ on the o t h e r hand, may not have been a b le to
a r r i v e a t some s o r t o f "Ii k e - u n l i k e " d e c i s i o n due t o d i f f e r e n c e s in
the e f f i c i e n c y o f a c c e s s i n g memory co d es .
This would tend to produce
a s h i f t in c r i t e r i o n as evidenced by a high er frequency o f g u e s s i n g .
This h y p o t h e s i s i s supported by t h e s h i f t in the mean r a t i n g category
value i l l u s t r a t e d in Figure 3.
D i f f e r e n c e s in the manner o f p r o c e s s i n g st im u lu s m a t e r i a l s may
a l s o account f o r the d i f f e r e n c e s in performance between the two reading
achievement groups,
Underwood and Bargh (1982) s u g g e s t t h a t when
d i s t i n c t i v e f e a t u r e s are not a v a i l a b l e in l e t t e r s t r i n g s r e c o g n i t i o n
w i l l be more l i k e l y t o proceed through a s e r i a l scanning s t r a t e g y .
The
use o f l e s s f re q u en t l e t t e r combinations as in the ca s e o f the Low
meaningful n ess CVC prov ide s fewer cues f o r phonological coding in much
t h e same manner as using u n f a m i li a r combinations o f l e t t e r form w i l l
do.
When l e t t e r combinations are high in m e a n in g f u ln e s s , and,
t h e r e f o r e , more f a m i l i a r , t hey w i l l be proces se d as a s i n g l e u n i t .
The
33
The High WRAT group was more aware o f t h e f a m i l i a r i t y o f t h e
combination, and was more e f f i c i e n t in t h e use o f a r e c o g n i t i o n
strategy.
The Low WRAT group f a i l e d t o use t h i s information
efficien tly.
This view i s supported by H e a ly 's 1981 d i s c u s s i o n o f th e r u le s
readers use to pro ces s reading u n i t s .
She s u g g e s t s t h a t readers g i v e
more p r i o r i t y t o r e s o l v i n g the general shape (or en vel ope ) o f a group
o f l e t t e r s when s ea rc h in g f o r a t a r g e t l e t t e r .
When t h e group o f
l e t t e r s i s w r i t t e n in a l t e r n a t e upper and lower ca s e l e t t e r s , c r e a t i n g
an u n f a m i li a r l e t t e r p a t t e r n , t a r g e t r e c o g n i t i o n i n c r e a s e s .
She
s u g g e s t s t h i s i s due to the n e c e s s i t y f o r p r o c e s s in g each l e t t e r in
u n f a m i li a r ma ter ia l as an i n d iv i d u a l u n i t .
On the o t h e r hand, s u b j e c t s
f a i l e d t o re c o g n i z e t a r g e t T e t t e r s e f f i c i e n t l y when the l e t t e r was
imbedded in material t h a t could be p roc es se d as a common, f a m i l i a r
unit.
These f e a t u r e s o f l e t t e r s t r i n g p r o c e s s in g may account f o r the
performance d i f f e r e n c e s between the two reading groups, and may a l s o
provide c l u e s t o the d i f f e r e n c e s in s e n s i t i v i t y noted a c r o s s
meaningful n es s c o n d i t i o n s .
The High WRAT group appeared t o be aware
o f th e f e a t u r e s o f t h e High CVC, w h i le the Low WRAT group did not.
Coding s t r a t e g i e s were t h e r e f o r e l e s s e f f i c i e n t and more s u s c e p t i b l e
t o d i s r u p t i o n s i n c e they were not u t i l i z i n g the meaningful ness
information t h a t was a v a i l a b l e .
v
34
Summary and Conclusions ■
This study has measured d i f f e r e n c e s in r e c o g n i t i o n memory
performance as a f u n c t io n o f the s u b j e c t v a r i a b l e reading achievement
l e v e l as measured by a t e s t o f r e c o g n i t i o n reading.
While t h e r e were no s i g n i f i c a n t d i f f e r e n c e s between reading
achievement groups as a f u n c t io n o f s e n s i t i v i t y to sti mu lus
c o n d i t i o n s , s i g n i f i c a n t v a r i a t i o n s in t h e manner in which t h e two
groups used th e r a t i n g s c a l e occ urred.
These r e s u l t s were i n t e r p r e t e d
in terms o f d i s c u s s i o n s by Jackson ( 1 9 8 0 ) , Healy ( 1 9 8 1 ) , and Underwood
and Bargh (1982) t h a t s u g g es t e d t h a t d i f f e r e n c e s e x i s t e d in the manner
in which s u b j e c t s a c c e s s memory codes in r e c o g n i t i o n t a s k s .
The data
from t h i s study could not be used t o d i f f e r e n t i a t e between s t r a t e g i e s
t h a t may have been used.
The s t a t i s t i c a l measures employed in t h i s study appear to
provide a v i a b l e approach f o r an in -d ep th e v a l u a t i o n o f r e c o g n i t i o n
s t r a t e g i e s and p r o c e s s e s u t i l i z e d by s u b j e c t s in the r e c o g n i t i o n o f
le tte r strings.
I f a measure i s used t h a t confounds response b ia s .a n d
s e n s i t i v i t y , t h e r e i s no way o f knowing whether d i f f e r e n c e s in s u b j e c t
performance i s r e l a t e d t o one or to th e o t h e r .
A simple Old or New
response does confound t h e s e measures and g i v e s l i t t l e information
regarding t h e v a r i a b l e s o f i n t e r e s t .
The use o f the m u l t i - l e v e l c o n f id e n c e r a t i n g s c a l e measure o f
s e n s i t i v i t y and response b i a s allowed f o r an a n a l y s i s o f the
d i f f e r e n c e s in r e c o g n i t i o n s t r a t e g y , i , e . , response b i a s .
The s h i f t
35
in c o n f id en ce l e v e l s s u g g e s t s t h a t t h e r e may be a breakdown in st imulus
encoding and r e t r i e v a l mechanisms as a f u n c t io n o f reading achievement
lev el.
The weakness o f t h e p re s en t study i s t h a t w h i le t h e r e are
performance d i f f e r e n c e s as :a f u n c t io n o f reading achievement l e v e l ,
t h e r e i s not s u f f i c i e n t information to j u s t i f y an e x p l i c i t t h e o r e t i c a l
statement regarding th e e x a c t nature o f t h e d i f f e r e n c e s .
What i s
needed i s a measure t h a t a ll ow s f o r t h e development o f a h yp ot he sis
regarding the response, b ia s mechanism, and t h e encoding s t r a t e g i e s
underlying i t .
The development o f . s u c h a h yp o th e sis would provide a
conceptual framework t h a t could have important i m p l i c a t i o n s f o r the .
development o f remedial t ec h n iq u es f o r d y s l e x i c and minimal cerebral
d y s fu n ct i o n syndrome r ea d er s.
I f , as Jackson s u g g e s t s , the l e s s s k i l l e d reader i s simply not
e f f i c i e n t in the pro ces s o f a c c e s s i n g l e t t e r c o d e s , i t i s p o s s i b l e t h a t
changes in response b ia s are due t o th e s u b j e c t ' s i n a b i l i t y t o reach a
d e c i s i o n q u i c k l y , t h e r e f o r e lowering h i s / h e r co n f id en ce in th e accuracy
o f the re s p o n se .
Concentrating f u t u r e s t u d i e s on the r e l a t i o n s h i p
between meaningful n ess and t h i s s u b j e c t v a r i a b l e s , reading achievement,
in terms o f response b i a s may be a major i s s u e in determining the
s t r u c t u r e o f th e d i f f e r e n c e s in r e c o g n i t i o n performance.
The a d d it io n
o f a response time measure t o the p r e s e n t paradigm, combined with a
m u l t i v a r i a t e approach to t h e mean r a t i n g ca t ego ry measure, would more
c om p le t e ly address t h e v a r i a b l e s o f i n t e r e s t and provide another f a c e t
to th e information regarding the nature o f response b i a s .
Such an
36
approach would a ll o w f o r a more p r e c i s e e v a l u a t i o n o f t h e s t r a t e g i e s
u t i l i z e d by s u b j e c t s wit h reading d i s a b i l i t i e s in l e t t e r s t r i n g
recognition.
37
REFERENCES
38
REFERENCES
Gibson, E. J . P r i n c i p l e s o f perceptual l e a r n in g and development.
New York: A pp l e t o n -C e n t u r y - C r o f t s , 1969.
Gleitman, H.
Ps y ch o lo g y .
New York:
W. W. Norton & Co, 1981.
Green, D. M., and S w e t s , J . A. Signal d e t e c t i o n theo ry and
p s y c h o p h y s i c s . New York: W iley, 1966.
G u il f o r d , J . P.
1954.
Psychometric methods, (ed . 2 ) .
New York:
H e a ly , A. F. C og ni t iv e p r o c e s s e s in reading t e s t .
10, 119-226.
McGraw-Hill,
C o g n i t i o n , 1981,
Jackson, M. D. Further e vi de nc e f o r a r e l a t i o n s h i p between memory
a c c e s s and reading a b i l i t y / Journal o f Verbal Learning and
Verbal B eh a vi or , 1980, 4 9 , 683-694.
J a s t a k , J. F . , B i j o u , S. W., and J a s t a k , S. R. Wide Range Achievement
T e s t . Guidance A s s o c i a t e s o f Delaware, I n c . , Wilmington,
Delaware, 1965.
Keppel, G . , and Underwood, G. J. Reminiscence in th e s h ort -t erm
retention of paired-associate l i s t s .
Journal o f Verbal
Learning and Verbal Beh a v io r, 1967, 6_, 375-382.
McNemar, Q. P s yc h o lo gi ca l S t a t i s t i c s ,
and S o n s , I n c, 1969.
(ed. 2)
McNicol, D. A primer o f s i g n a l d e t e c t i o n t h e o r y .
A lle n and Unwin Ltd, 1972.
New York:
London:
John Wiley
George
Noble, C. E. Measurements o f a s s o c i a t i o n value ( a ) , rated
a s s o c i a t i o n s ( a / ) and s c a l e d meaningful ness (m'). f o r the 2100
CVC combinations o f the English a lp h a b et . Ps y c h o lo g i c a l
R e p o r t s , 1961, fj, 478-521.
P e t e r s o n , L. R ., P e t e r s o n , M. J . , and M i l l e r , A. Short-term r e t e n t i o n
and meaningful n e s s . Canadian Journal o f P s y c h o lo g y , 1961, 15_,
143-147.
R a se r, G. A. Meaningful n ess and s i g n a l - d e t e c t i o n theory in *immediate
p a i r e d - a s s o c i a t e r e c o g n i t i o n . Journal o f Experimental
Ps ych olo gy, 1970, M , 173-175.
'39
S h o n t z» W. D. Factors a f f e c t i n g the p r o c e s s in g o f s e q u e n t i a l l y
p re se nt ed form p a r t s ! Unpublished do ctoral d i s s e r t a t i o n , Iowa
S t a t e U n i v e r s i t y , 1967.
Snedecor5 G. W., and Cochran, W. G. S t a t i s t i c a l Methods, (ed. 7 ) ,
Ames5 Iowa: The Iowa S t a t e U n i v e r s i t y P r e s s 5 1980.
Thompson-Gibbs5 A. The e f f e c t s o f meaningful ness on th e r e c o g n i t i o n
o f CVC t r i grams: a s i g n a l - d e t e c t i o n paradigm. Unpubli shed
undergraduate s t u d y , Montana S t a t e U n i v e r s i t y , 1972.
Underwood5 G., and Bargh5 K. Word shape, orthographic r e g u l a r i t y ,
and con tex tu al i n t e r a c t i o n s in a reading t a s k . C o g n i t i o n 5
1982, 12_, 197-209.
Underwood5 B. J . , and S c h u lz , R. W. Meaningful n ess and verbal
l e a r n i n g . New York: L i p p i n c o t t 5 1960.
Wallach5 M. A. Perceptual r e c o g n i t i o n o f approximations t o English
in r e l a t i o n to s p e l l i n g achievement. Journal o f Educational
■Psychology, 1963, 54 , 57-62.
40
APPENDICES
41
APPENDIX A
I n s t r u c t i o n s t o Subj ec ts
The ta s k you are about to perform i s a r e c o g n i t i o n t a s k .
You
w i l l be scored on the amount o f information you are a b le t o r e c o g n i z e .
The s l i d e s you w i l l s e e on the scree n b e f o r e you are known as CVC or
consona nt-vo wel-co nson an t t r ig r a m s .
f l a s h e d on the s c r e e n .
A s e r i e s o f t h e s e CVCs w i l l be
I t w i l l be n e c e s s a r y f o r you t o keep your eyes
focu sed on the screen during p r e s e n t a t i o n as they w i l l be. f l a s h e d very
quickly.
.
.
At the end o f t h e f i r s t s e r i e s , you w i l l be given a f i f t e e n
second break.
During t h i s break you are t o count backwards by t h re es
from one hundred--out lo ud .
At the end o f t h i s f i f t e e n second p er i o d ,
you w i l l be t o l d t o s t o p co u n t in g .
s e t o f s l i d e s on the s c r e e n .
I w i l l then begin t o show another
Half o f t h e s e s l i d e s w i l l be the CVCs
t h a t you saw during t h e f i r s t p r e s e n t a t i o n ; the o t h e r h a l f w i l l be new
CVCs--Ones t h a t y o u 'v e not seen b e f o r e .
They w i l l appear on the
scree n f o r t h e same le n g t h o f time as during the p r e s e n t a t i o n o f the
f i r s t s e r i e s , but t h e r e w i l l be a lo n g er period o f time between the
s l i d e s t o g i v e you an op p o rtu ni ty t o respond.
Your t a s k , a f t e r s e e i n g each s l i d e in the second s e r i e s , w i l l
be to respond with a number t h a t i n d i c a t e s a s p e c i f i c r es p o n se .
numbers you use w i l l be I , 2 , 3 , 4 , 5 , or 6.
The
The numbers on e, two
and t h r e e i n d i c a t e t h a t you b e l i e v e t h e CVC you have j u s t seen i s an
42
OLD CVC, or one you have seen b e f o r e ,
ONE means t h a t you are VERY'
SURE; TWO, t h a t you are FAIRLY SURE; and THREE, t h a t you are only
GUESSING t h a t i t i s an OLD CVC..
The numbers f o u r , f i v e , and s i x i n d i c a t e t h a t you b e l i e v e the
CVC t h a t . y o u have j u s t seen i s a NEW on e, or one t h a t you have not
seen p r e v i o u s l y .
The numbers f o u r , f i v e , a n d s i x , however, DO NOT
FOLLOW THE SAME PATTERN OF CONFIDENCE RATING.
The l a r g e s t number,
SIX, in t h i s c a s e , i n d i c a t e s t h a t you are VERY SURE; FIVE, t h a t you
are FAIRLY SURE; and FOUR, the s m a l l e s t number, i n d i c a t e s t h a t you are
j u s t GUESSING t h a t the CVC i s new.
Be sure t h a t you use a l l o f the resp on se s a v a i l a b l e t o you i f
i t i s a p p ro p ri a t e.
I t i s o nly r a r e l y tr u e t h a t you are very sure or
g u e s s i n g a l l o f th e time .
Don't l e t t h i s confuse you.
You w i l l be
given the o p p or tu ni ty to p r a c t i c e the s c a l e u n t i l you are ea s e with i t
There w i l l be two: s e t s o f p r a c t i c e s l i d e s shown to you so t h a t
you can p r a c t i c e the r a t i n g s c a l e and le a rn t o pace y o u r s e l f to the
rate o f presentation.
The f i r s t s e t o f p r a c t i c e s l i d e s has ten OLD
CVCs; the second has. f i f t e e n .
Feel f r e e to ask q u e s t i o n s during the
p r a c t i c e s e s s i o n s , and t o s t o p me i f you need to d i s c u s s the use o f
the rating s c a le .
The actu al experimental t r i a l s w i l l c o n s i s t o f two block s o f
trials.
Each block w i l l use 25 OLD CVCs, then FIFTY C V C s - h a l f w i l l
be NEW CVCs; the o t h e r h a l f OLD.
43
APPENDIX B
Post Experimental Qu es tionnaire
Condition_________________________ _
Name____________________ __________
P l e a s e answer t h e f o l l o w i n g q u e s t i o n s to the b e s t o f your
a b i l i t y . When q u e s t i o n s re q u ir e a YES.or NO re s p o n se , check the
ap pro pr iat e answer. Other q u e s t i o n s may req uir e a check in the
ap pro pri at e s p a c e , and in a d d i t i o n , ask you t o make comments regarding
your a c t i v i t i e s during th e experimental t r i a l in which you have j u s t
p a r t i c i p a t e d . Make your answers c o n c i s e but as e x p l i c i t as p o s s i b l e .
There i s space at the end o f t h i s q u e s t i o n n a i r e f o r any f u r t h e r
comments you care t o make regarding t h e s e q u e s ti o n s or any^ot h er
a s p e c t o f the stud y.
1.
Did you do anything s p e c i a l t o help you remember each CVC as i t
was presen ted to you?
YES___ NO____
la.
I f your answer was YES, what did you do?
1) Pronounce i t or attempt to?
2) Said each l e t t e r s e p a r a t e l y ?
3) Something e l s e ? EXPLAIN
2.
Did you attempt to r e l a t e the CVC trigrams to something meaningful
t o you? As an example, DEC might be December, or JAN, a name.
YES_____NO_____
3.
Did you do anything s p e c i a l t o help you deci de whether a trigram
was OLD or NEW? YES____ NO_____
3a. I f
YES, what did you do, t h i n k , or look for?
EXPLAIN.
4.
Once you had decided on what to look f o r in making
did you change your s t r a t e g y ? YES____ NO_____
4a.
I f you d i d , how did you change what you were doing?
5.
Did you n o t i c e any d i f f e r e n c e s in the co n te n t o f t h e trigrams?
YES____ NO_____
5a.
I f YES, what were th e d i f f e r e n c e s ?
EXPLAIN.
a decision,
EXPLAIN.
44
6.
When you responded with . , 2 , or 3 , and 4 , 5, and 6 , did th ose
resp onses a c c u r a t e l y r e f l e c t a d i f f e r e n c e in your l e v e l o f .
co n fid en ce? In o t h er words» did ONE mean t h a t you were r e a l l y
sure i t was OLD, and FOUR r e a l l y mean t h a t you were g u es sin g
t h a t the CVC was NEW? Were a l l o f your responses a cc u ra t e in
t h e s en se o f c o n f id e n c e in the OLD or NEW r a tin g ? YES____ NO_____
6a.
I f your answer i s NO, p l e a s e e x p l a i n why.
7.
Should t h e r e have be,en MORE resp on se s a v a i l a b l e , r e p r e s e n t i n g
in t e r m e d i a t e s t e p s between the resp on se s you were using?
YES____ NO
8.
Were t h e r e any ph ysi cal c h a r a c t e r i s t i c s o f the s l i d e s t h a t helped
you d i f f e r e n t i a t e between s l i d e s ? .YES____NO_____
8a.
I f YES, what were they?
P l e a s e make any ot h er comments regarding t h e methods you used to make
OLD and NEW d e c i s i o n s t h a t w i l l e x p l a i n your s t r a t e g y .
THANKS FOR TAKING PART IN THE STUDY.
MONTANA STATE UNIVERSITY LIBRARIES
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N378.T3795@Theses
The effects of subject's reading achieve
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The e f f e c t s o f s u b j e c t s
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in a r e c o g n it io n memory
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