IDENTIFYING PRE-SERVICE PHYSICS TEACHERS’ MISCONCEPTIONS WITH
THREE-TIER TESTS
Derya Kaltakci1,* and Ali Eryilmaz2
1
Department of Secondary Science/Math. Education, Middle East Technical University, Ankara, Turkey,
kaderya@metu.edu.tr
2
Department of Secondary Science/Math. Education, Middle East Technical University, Ankara, Turkey,
eryilmaz@metu.edu.tr
Abstract
In order to measure individuals’ conceptions, different diagnostic tools have been developed
and used such as; interviews, multiple choice tests, concept maps, and multiple-tier tests (two
tier tests and three tier tests). Among these tools, interviews have advantages as flexibility and
obtaining in-depth information. However; interviews can be conducted on limited number of
individuals. Multiple choice tests can be administered to a large number of individuals; but
cannot investigate the students’ responses deeply. In order to compensate the limitations of
interviews and the ordinary multiple choice tests, researchers extended multiple choice tests
into two or three-tier tests. With the application of three-tier tests to determine
misconceptions, researchers can obtain rich information about the individuals’
misconceptions eliminated from lack of knowledge and errors.
Some previous research studies draw attention to the teachers as a possible source of student
misconceptions. For this reason, identifying teachers’ and teacher candidates’ misconceptions
become crucial to better understand the ones of students’. In the present study, three different
three-tier concept tests on geometric optics, simple electric circuits and force and motion were
administered to 30 senior pre-service physics teachers at Middle East Technical University
(METU) in Turkey to analyze their misconceptions. For each of the three topics, common
misconceptions measured by each of the tests are listed. Pre-service physics teachers’
misconceptions in all three topics is analyzed and presented for one, two and three tiers
separately in terms of percentages of each misconception.
Introduction
Misconceptions are stable, unscientific conceptions that obstacle the real learning of
individuals (Kaltakci & Didis, 2007) and Hammer (1996) listed the properties of
misconceptions as:
1) Misconceptions are strongly held and stable cognitive structures,
2) Differ from expert conception,
3) Affect how students understand scientific explanations,
4) Must be overcome, avoided and eliminated to achieve expert conception.
For this reason, identification and elimination of misconceptions about several science
concepts is a popular research area in educational research. In order to identify and measure
students’ misconceptions different diagnostic tools have been developed and used. Interviews,
multiple choice tests, concept maps and multiple-tier tests can be listed as diagnostic tools for
misconceptions in science education. Each of these tools has some advantages as well as
disadvantages over the others.
* On behalf of Department of Secondary Science/Math. Education, Kocaeli University, Kocaeli, Turkey
1
Interviews provide in-depth information about the students’ cognitive structures and
reasoning by its probing and flexibility. Several interviewing techniques have been used such
as Piagetian Clinical Interviews (PCI) (Piaget as cited in White & Gunstone, 1992),
Interview-About-Instances (IAI) (Osborne & Gilbert, 1979), Interviews-About-Events (IAE)
(Osborne & Gilbert, 1980), Prediction-Observation- Explanation (POE) (White & Gunstone,
1992), Individual Demonstration Interview (IDI) (Goldberg & McDermott, 1986, 1987),
Teaching Experiment (TE) (Katu, Lunetta, & van den Berg as cited in Komorek & Duit,
2004). However interviews as diagnostic tools have certain disadvantageous as can be
conducted on limited number of individuals.
For overcoming the disadvantage in interviewing, diagnostic multiple choice tests
(Treagust & Haslam as cited in Chen, Lin, & Lin, 2002) that can be immediately scored and
applied to a large number of subjects have been used to ascertain students’ conceptions. These
tests have been used either following in-depth interviews or alone. However these tests cannot
investigate the students’ responses deeply. In literature there exist several examples of
multiple choice tests developed by Linke and Venz, Tamir, Trembath (as cited in Chen et al.,
2002), and Hestenes, Wells and Swackhamer (1992).
Ordinary multiple choice tests with one-tier were criticized in overestimating the
students’ wrong answers. Because, some of these wrong answers of students may not be due
to students’ misconceptions, but due to lack of knowledge or error. In order to eliminate the
limitation of one-tier tests, two-tier tests developed by researchers. Treagust (1985) and Chen
et al. (2002) developed two-tier tests with ordinary multiple choice question in the first tier
and asking the reasoning in the second tier. Eryilmaz and Surmeli (2002) developed a threetier test about heat and temperature and in their test in addition to the first two tiers they asked
students’ confidence about their answers in the third-tier. Afterwards, three tier tests used by
many other researchers (Aydin, 2007; Kutluay, 2005; Peşman, 2005; Türker, 2005).
The main sources of students’ misconceptions are categorized as the students’ personal
experiences, textbooks, language used, and teachers. Since teachers have a crucial influence
on students’ learning, an effective pre-service and in-service teacher education process
becomes important. For this reason one of the aims of this study is to identify misconceptions
of pre-service physics teachers on the topics of “Geometric Optics”, “Force and Motion”, and
“Simple Electric Circuits” with three-tier misconception tests to guide effective teacher
education attempts in future. The second aim of the study is to give information about threetier misconception tests.
Methodology
Population and Sample
In order to analyze pre-service physics teachers’ misconceptions on three topics:
“Geometric Optics”, “Force and Motion”, and “Simple Electric Circuits”, a cross sectional
survey study was conducted on 30 senior pre-service physics teachers with 11 girls (37%), 19
boys (63%) at Middle East Technical University (METU) in Turkey. The target population of
the study was all senior pre-service physics teachers at METU (approximately 40 students).
Instruments
Three three-tier misconception tests from literature were used for this study. These are
Geometric Optics Misconception Test (GOMT) (Kutluay, 2005), Force and Motion
Misconception Test (FMMT) (Turker, 2005), and Simple Electric Circuits Misconception
Test (SECMT) (Pesman, 2005).
In the development of the three-tier tests, a certain process is followed. Firstly, semistructured interviews with participants similar to the intended sample of the test are done. At
2
this step, common misconceptions on the topic are determined, it gives time to think to the
participants, to elaborate on their answers and reasoning, and also gives an opportunity to the
researcher to obtain an in depth information. After the interviews, open-ended tests are
developed and administered to get greater generalizibility and to create the distracters of the
three-tier tests. After analyzing the results of open-ended tests, three tier-tests are developed.
In the development process, the interview results and the misconceptions found in literature
are also taken into account. All of the instruments are developed for high school students in
Turkey. The validity and reliability analysis are done by the researchers. In this present study
however, these three tests are administered to pre-service physics teachers who are going to
be teachers at high schools in future. The three different three-tier misconception tests were
administered during an approximately 30-35 minutes each on different days.
Data Analysis
In order to analyze misconceptions with three tier tests a descriptive statistical analysis
conducted with percentages. For the validity of the test scores three quantitative techniques
are used. Firstly, correlation between test scores on the first two tiers and confidence levels on
the third tiers are determined to establish construct validity. Since if the test is effective, it is
expected that students with higher scores on first two tiers would be more confident about the
correctness of their answers (Çataloğlu, 2002). As a second method for validity, factor
analysis method is used to determine whether there are one or more clusters of items on the
test scores. Thirdly, probabilities of false positive and false negatives are estimated for content
validity. False positive is defined as Newtonian response chosen with a non-Newtonian
reason. False negatives, on the other hand, are non-Newtonian response that is chosen by
Newtonian thinker. False negatives are considered unproblematic and attributed to the
carelessness or inattention. According to Halloun and Hestenes (1995), the probability of
false negatives should be less that 10%.
In the analysis of a three-tier test, if a student chooses incorrect choice in the first tier,
then chooses incorrect reasoning in the second tier and sure about the responses in the first
two tiers, then the student is considered to have misconception. Other responses are attributed
to either errors or lack of knowledge.
Results
The GOMT, FMMT, and SECMT measures the pure misconceptions of pre-service
teachers which are eliminated from lack of knowledge and errors with three tiers. In the first
tiers of the tests pre-service teachers are asked about the concepts, in the second tiers they are
asked to explain their reasons in the first tiers, and in the third tiers they are asked to what
degree they are sure about their given responses in the first two tiers. With this way of
measurement, each distracter in the multiple choice test corresponds to a misconception listed
previously. Each categorized misconception is determined by the selection of one or more
related distracters of several items from the test. However different from a one or two tier test
in a three tier test we can determine pure misconceptions. Table 1 shows the misconceptions
measured by the GOMT, the items that correspond to these misconceptions, percentage of
pre-service teachers having each misconception from the present study, and the percentage of
3
Table 1 Comparison of Misconception Categories for High School Students and Pre-service Teachers for the All Three tiers of GOMT
Misconceptions (Items)
M1 Light colored objects can be seen in total darkness since they emit light. (1.1.a, 1.2.e, 1.3.a) (12.1.a, 12.2.b, 12.3.a)
M2 There will be black rays in the total darkness. (1.1.b, 1.2.a, 1.3.a) (12.1.a, 12.2.e.12.3.a)
M3 Eyes can get used to seeing in total darkness. (1.1.c,d, 1.2.b, 1.3.a) (12.1.a, 12.2.d, 12.3.a)
M4 Light travels a different distance depending upon whether it is day or night. (2.1.a.,2.2.a,f,g, 2.3.a) (2.1.b, 2.2.b,c,e, 2.3.a)
M5 Light is emanating in only one direction from each source, like flash light beams. (3.1.b, 3.2.b, 3.3.a) (5.1.a, 5.2.b, 5.3.a)
M6 Shadows of the objects are clearer when the bigger bulb is used as a light source. (3.1.b, 3.2.a, 3.3.a) (4.1.a, 4.2.b, 4.3.a)
M7 Shadow belongs only to the non-luminous object and it always looks like the object. (5.1.a,b,d, 5.2.c, 5.3.a)
M8 Students claim that there will be no shadow even if a light source and a non- transparent object exist together. (5.1.e, 5.2.a, 5.3.a)
(6.1.a, 6.2.e, 6.3.a)
M9 In the region of geometrical overlap there would be either lightness (full illumination) or darkness (shadow). They did not
consider semi darkness and treated the shadow as the presence of something. (6.1.b, 6.2.b, 6.3.a) (6.1.d, 6.2.a, 6.3.a)
M10 Shadow is black color and light is white color. When they overlap, they mix and form the grey color. When the shadow and
light overlap, the shadow reduce the brightness of the light. (6.1.c, 6.2.d, 6.3.a)
M11 To see an image of any object, it should be inside the front region straight ahead of the mirror. (7.1.c, 7.2.c, 7.3.a) (15.1.b,
15.2.b, 15.3.a)
M12 Students think that an image in a plane mirror lies behind the mirror along the line of sight between a viewer and the object.
(7.1.a, 7.2.a, 7.3.a) (11.1.a, 11.2.d, 11.3.a) (13.1.b, 13.2.a, 13.3.a) (15.1.b, 15.2.c, 15.3.a) (16.1.b, 16.2.c, e, 16.3.a)
M13 An observer sees the object because the observer directs sight lines toward it, with light possibly emitted from the eyes. (7.1.b,
7.2.e, 7.3.a) (11.1.a, 11.2.b, 11.3.a) (15.1.a, 15.2.a,d, 15.3.a) (8.1.a, 8.2.f, 8.3.a)
M14 Confuse image formation with shadow formation. In the presence on an illuminant the position and size of the image of an
illuminated object depends on the illuminant. (8.1.a, 8.2.g,h, 8.3.a) (8.1.b, 8.2.ab,c,, 8.3.a) (8.1.c, 8.2.c, 8.3.a) (9.1.a, 9.2.a,b,c, 9.3.a)
(9.1.b, 9.2.d,e, 9.3.a)
M15 The position and size of the image of any object depend on the location of the observer. When the observer retreats size and
position of the observer is changed. (10.1.a, 10.2.a,b,c, 10.3.a) (10.1.c, 10.2. k, 10.3a)
M16 Image of a black object on the mirror was due to black rays bouncing off the black object. (11.1.a, 11.2.a, 11.3.a)
M17 Creating images are an inherent attribute of the silvery mirror material, rather than the product of the reflection process. The
students say that “The mirror reflects and so the person sees”. (12.1.a, 12.2.c, 12.3.a)
M18 While watching an object its position also shifted as they viewed it from different perspectives. They misunderstand that the
absolute position of the object remains the same as an observer moves. (13.1.b, 13.2.a,d, 13.3.a)
M19 Image of any object is located right ahead of the observer. (13.1.b, 13.2.b,f, 13.3.a) (16.1.b, 16.2.a,f, 16.3.a)
M20 To see him in a dark room, he or she should illuminate the mirror rather than himself. (14.1.b, 14.2.b,c, 14.3.a)
AVERAGE
4
% of
Preservice
(N=30)
4
3
3
0
17
20
3
7
% of High
School
(N=141)
10
13
23
31
17
30
19
7
10
17
27
30
0
12
73
18
27
18
10
23
7
21
7
7
14
10
10
25
0
13
29
25
12
19
high school students having each misconception from the study of Kutluay (2005). According
to the analysis of data the average misconception percentage for pre-service teachers is 12,
whereas the average misconception percentage for high school students is 19 for the same
test. 73 percent of the pre-service teachers have the misconception labeled as M12 (an image
in a plane mirror lies behind the mirror along the line of sight between a viewer and the
object) whereas only 18 percent of the high school students have this misconception. None of
the pre-service teachers have the misconception labeled as M4, on the other hand 31 percent
of the high school students have the same misconception. Table 2 illustrates the analysis of
the GOMT results of pre-service teachers for one tier, two tier and three tiers separately.
According to the results, if only first tiers of the test are considered an average of 33 percent
of misconceptions present for pre-service teachers, if first two tiers of the test considered an
average of 15 percent of misconceptions present, and when all three tiers are considered an
average of 12 percent of misconceptions present for pre-service teachers. Comparing the
analysis for only first tiers and first two tiers a percentage of 18 is predicted to be due to the
errors in answers. Also, comparing the analysis for first two tiers and all three tiers a
percentage of three is attributed to the lack of knowledge.
Table 2 Percentages of the Misconceptions of Pre-service Teachers Considering the Tiers of the
GOMT
All Three Tiers First Two Tiers Only First Tiers
M1
M2
M3
M4
M5
M6
M7
M8
M9
M10
M11
M12
M13
M14
M15
M16
M17
M18
M19
M20
AVERAGE
4
3
3
0
17
20
3
7
10
27
0
73
27
10
7
7
7
10
0
13
12
7
7
3
0
17
20
7
10
13
27
3
80
43
17
10
7
7
10
0
13
43
43
43
7
7
60
40
60
20
20
33
50
43
20
3
0
27
13
30
37
15
33
Similarly Table 3 presents the comparison of misconception categories with percentages
for high school students from the study of Turker (2005) and pre-service teachers for the all
three tiers of FMMT. The most striking results appear in I4, I5, and AF6 between both
samples. According to Table 4, three tier analyses reveal that six percent of the
misconceptions are attributed to errors, and three percent is to the lack of knowledge.
Table 5 shows the comparison of misconception categories with percentages for high
school students from the study of Pesman (2005) and pre-service teachers for the all three
tiers of SECMT, and M3 and M11 seems somehow different for the two samples.
5
Table 3 Comparison of Misconception Categories for High School Students and Pre-service Teachers for the All Three tiers of FMMT
Misconceptions (Items)
I1 Impetus supplied by hit (7.1 a, 7.2 c, 7.3 a/b), (7.1 b, 7.2 a, 7.3 a/b), (16.1 b, 16.2 b, 16.3 a/b), (16.1 c, 16.2 a, 16.3 a/b)
I2 Loss/ Recovery of original impetus (5.1 c, 5.2 a, 5.3 a/b), (14.1 a, 14.2 c, 14.3 a/b), (14.1 c, 14.2 b, 14.3 a/b)
I3 Impetus dissipation (4.1 a, 4.2 b, 4.3 a/b), (4.1 b, 4.2 c, 4.3 a/b), (6.1 b, 6.2 c, 6.3 a/b)
I4 Gradual/ delayed impetus build- up (6.1. c, 6.2 a, 6.3 a/b), (12.1 c, 12.2 a, 12.3 a/b)
I5 Circular impetus (3.1 a, 3.2 c, 3.3 a/b), (3.1 b, 3.2 c, 3.3a/b)
AF1 Only active agents exert force (2.1 a, 2.2 c, 2.3 a/b), (15.1 a, 15.2 d, 15.3 a/b)
AF2 Motion implies active force (2.1 c, 2.2 a, 2.3 a/b), (2.1 d, 2.2 e, 2.3 a/b), (11.1 b, 11.2 b, 11.3 a/b), (11.1 c, 11.2 a, 11.3 a/b)
AF4 Velocity proportional to applied force (13.1 a, 13.2 b, 13. 3 a/b)
AF6 Force causes acceleration to terminal velocity (13.1 c, 13.2 a, 13.3 a/b)
AR1 Greater mass implies greater force (1.1 a, 1.2 c, 1.3 a/b), (1.1 c, 1.2 b, 1.3 a/b), (8.1 b, 8.2 a, 8.3 a/b), (15.1 b, 15.2 a, 15.3 a/b)
AR2 Most active agent produces greatest force (8.1 c, 8.2 b, 8.3 a/b), (9.1 b, 9.2 d, 9.3 a/b), (15.1 b, 15.2 b, 15.3 a/b)
CI1 Largest force determines motion (8.1 c, 8.2 d, 8.3 a/b), (9.1 b, 9.2 c, 9.3 a/b), (10.1 a, 10.2 b, 10.3 a/b), (10.1 c, 10.2 a, 10.3 a/b)
CI2 Force compromise determines motion (5.1 b, 5.2 d, 5.3 a/b), (12.1 b, 12.2 c, 12.3 a/b)
CI3 Last force to act determines motion (5.1 a, 5.2 b, 5.3 a/b), (12.1 a, 12.2 d, 12.3 a/b)
CF Centrifugal force (2.1 e, 2.2 b, 2.3 a/b), (3.1 d, 3.2 a, 3.3 a/b), (3.1 e, 3.2 a, 3.3 a/b), (11.1 d, 11.2 c, 11.3 a/b)
Ob Obstacles exert no force (9.1 c, 9.2 a, 9.3 a/b)
AVERAGE
% of
Preservice
(N=30)
23
7
7
0
7
0
27
7
3
3
7
30
10
17
7
23
% of High
School
(N=188)
18
26
30
33
43
4
24
13
35
29
11
28
10
12
8
17
11
21
Table 5 Comparison of Misconception Categories for High School Students and Pre-service Teachers for the All Three tiers of SECMT
Misconceptions (Items)
M1 Sink Model (1.1 a, 1.2 a, 1.3 a), (10.1 a, b, 10.2 b, 10.3 a)
M2 Attenuation Model (4.1b, c, 4.2 c, 4.3 a)
M3 Sharing Current Model (3.1 b, 3.2 c, 3.3.a), (3.1 a, 3.2 c, 3.3.a), (4.1 d, 4.2 c, 4.3 a), (5.1 a, b, 5.2 c, 5.3 a)
M4 Clashing Current Model (1.1 b, 1.2 b, 1.3 a), (10.1 a, 10.2 a, 10.3 a)
M5 Empirical Rule Model (4.1 b, 4.2 a, 4.3 a), (7.1 b, 7.2 b, 7.3 a), (12.1.a, 12.2.b, 12.3 a)
M6 Short Circuit Misconception (8.1 b, 8.2 b, 8.3 a), (8.1 c, 8.2 c, 8.3 a), (10.1 a, 10.2 c, 10.3 a), (12.1 b, 12.2 d, 12.3 a)
M7 Power Supply as a Constant Current Source Model (3.1a, c, 3.2 a, 3.3 a), (5.1 c, 5.2 e, 5.3 a), (9.1 d, 9.1 d, 9.3 a)
M8 Parallel Circuit Misconception (5.1 a, 5.2 a, 5.3 a)
M9 Sequential Reasoning (9.1 a, 9.2 a, 9.3 a), (9.1 c, 9.2 b, 9.3 a)
M10 Local Reasoning (2.1 a, 2.2 a, 2.3 a), (5.1 a, 5.2 b, 5.3 a), (12.1 a, 12.2 c, 12.3 a)
M11Confusion Between Current Flow and Water Flow (6.1 a, 6.2 a, 6.3 a), (7.1 c, 7.2 a, 7.3 a), (11.1 a, 11.2 b, 11.3 a)
AVERAGE
6
% of
Preservice
(N=30)
3
0
0
10
0
17
7
0
0
10
0
% of High
School
(N=124)
5
4
11
26
4
16
9
2
4
15
8
4
9
Table 4 Proportions of the Misconceptions of Pre-service Teachers Considering the Tiers of the
FMMT
Misconceptions
All Three Tiers First Two Tiers Only First Tiers
I1
I2
I3
I4
I5
AF1
AF2
AF4
AF6
AR1
AR2
CI1
CI2
CI3
CF
Ob
23
7
7
0
7
0
27
7
3
3
7
30
10
17
7
23
23
17
10
0
10
0
30
13
7
3
7
37
20
17
10
23
40
30
23
10
20
0
33
13
7
13
30
17
13
17
23
23
AVERAGE
11
14
20
According to Table 6, three tier analyses reveal that one percent of the misconceptions are
attributed to errors, and one percent to the lack of knowledge.
Table 6 Proportions of the Misconceptions of Pre-service Teachers Considering the Tiers of the
SECMT
Misconceptions
All Three Tiers First Two Tiers Only First Tiers
M1
M2
M3
M4
M5
M6
M7
M8
M9
M10
M11
3
0
0
10
0
17
7
0
0
10
0
3
0
0
10
0
23
7
0
0
13
0
30
0
0
0
0
7
10
0
0
13
3
AVERAGE
4
5
6
Conclusion and Discussion
Identification of pure misconceptions eliminated from errors and lack of knowledge is
crucial. Present study provides the literature with valuable information in two folds: firstly the
difference between one, two, tier analysis of three different concepts, secondly the
comparison of the misconception categories identified with these three concepts for preservice teachers and the high school students. The results show that analysis of
misconceptions with three tier tests eliminates the overestimation of one and two tier tests and
disadvantages of the other methods. Also results show that pre-service teachers even after
formal education have misconceptions on the three topics like high school students. For this
reason teachers should be considered as a source of their students’ misconceptions and a
special attention should be given to teacher education process.
7
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