Variables & Hypotheses

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The Research Spiral
Identify the
Research Problem
Evaluate Data
and
Write Report
Analyze and
Interpret
Data
Review the
Literature
Collect Data
Specify a
Research
Purpose
Identifying a Research
Problem
Research Problem is the focus of a
research investigation
Key Concepts





Defining the Research Problem
Distinguishing the problem from the research topic,
purpose and research questions
Determining the research approach
Introducing the problem
The flow of ideas in a problem statement
Research Problem Defined
A research problem is an
educational issue or concern
that an investigator presents
and justifies in a research study.
Distinguishing the Research Problem
From Other Research Steps




A research topic is the broad subject matter being
addressed in a study.
A research problem is an educational issue or
problem in the study
A purpose is the major intent or objective of the
study.
Research questions are questions the researcher
would like answered or addressed in the study.
Differences Among Topic, Problem,
Purpose and Questions
General
Topic
Specific
Distance Learning
Research
Problem
Lack of students in distance
classes
Purpose
Statement
To study why students do not
attend distance education classes at
a community college.
Research
Question
Does the use of web site technology
in the classroom deter students
from enrolling in a distance
education class?
Flow of Ideas in a Problem
Statement
FLOW OF IDEAS
Topic
Subject
Area
Educational
Issue
•A Concern
•A Problem
•Something
that needs a
solution
Evidence for
the
Issue
•Evidence from
the literature
•Evidence from
practical
experiences
Deficiencies
in the
Evidence
•In this body of
evidence, what is
missing?
•What do we
need to know
more about?
What
Remedying
the Deficiencies
will do for
Select
Audiences
How will
addressing
what we need to
know help:
researchers
– educators
– policy-makers
– individuals like
those in the study
Specifying a Purpose, Research
Questions or Hypothesis
Distinguishing among various forms
of direction in research
Purpose
Statement
Intent
Form
Overall
Direction
One or more
sentences
Use
Quantitative
and
Qualitative
Research
Placement
End of
Introduction
Research
Hypothesis
Questions
Raise questions
to be answered
Make predictions
about expectations
One or more
questions
One or more
questions
Research
Objectives
State Goals
One or More
Objectives
Quantitative
Quantitative
Typically
and
Research
Quantitative
Qualitative
Research
Research
End of the introduction, after the literature
review, or in a separate section of the study
Research Questions
By the end of this chapter, you should be
able to:


1. Give some examples of
potential research
problems in education
2. Formulate a research a
research question


3. Distinguish between
researchable and nonresearchable questions
4. Describe
characteristics that good
research questions
possess
Research Questions
Objectives (cont.)


5. Describe three
ways to clarify
unclear research
questions
6. Give an example
of an operational
definition and explain
how such definitions
differ from other
kinds of definitions

7. Explain what is
meant, in research,
by the term
“relationship” and
give an example of a
research question
that involves a
relationship
Research Questions???

Usually a research problem is initially
posed as a question, which serves a focus of
the researcher’s investigation
Examples of Possible Research
Questions


1. Does behavior
modification reduce
aggression in autistic
children (single subject
experimental research)
2. Are the descriptions
of people in social
studies textbooks
biased (content analysis
research).

3. What goes on in
an elementary school
classroom during an
average week?
(ethnographic
research)
Examples of Possible Research
Questions (cont.)


4. Do teachers behave
differently toward
students of different
genders? (causal
comparative research).
5. How can we predict
which students might
have trouble learning
certain kinds of subject
matter? (correlational
research)


6. How do parents
feel about the
school counseling
program? (survey
research)
7. How can a
principal improve
faculty morale?
(interview research)
Researchable Questions



What all these questions have in common is that
we can collect data of some sort to answer them
(at leas in part). That’s what makes them
researchable.
For example, a researcher can observe and
interview in order to describe the functioning of an
elementary school classroom.
To repeat, then, what makes these questions
researchable is that some sort if information can
be collected to answer them.
Non-researchable Questions


There are other
kinds of questions,
however, that cannot
be answered by
collecting analyzing
data. Here are two
examples:

1. Should
philosophy be
included in the
high school
curriculum?
2. What is the
meaning of life?
Non-Researchable?





Why can’t these questions be research?
What about them prevents us from collecting
information to answer them?
The first question is a question of value -
It does not have any empirical (or observable)
referents.
The second question: Answers to this sort of
question lie beyond the accumulation of
information.
Which ones (if any) do you
think are researchable?
1. Is God good?
2. Are children happier
when taught by a
teacher of the same
gender?
3. Does high school
achievement
influence the
academic
achievement of
university students?


4. What is the best
way to teach
grammar?
5. What would
schools be like today
if World War II had
not occurred?
Researchable?


. Q. 4. Think about
this for a moment.
Is there any way we
can determine the
best way to do
something?
To be able to
determine this, we
must examine every
possible alternative,


and a moment’s
reflection brings us
to realize that this
can never be
accomplished.
How would be ever
be sure that all
possible alternatives
have been
examined?
Researchable?

Q. 5 requires the creation of impossible
conditions. We can, of course investigate
what people think schools would be like.
Researchable vs. Non-researchable Questions
Figure 2.1
6
Characteristics of Good Research Questions
Page 30
5
1.
The question is feasible (i.e., it can be investigated without an
undue amount of time, energy, or money).
2.
The question is clear (i.e., most people would agree as to what the
key words in the question mean).
3.
The question is significant (i.e., it is worth investigating because it
will contribute important knowledge about the human condition).
4.
The question is ethical (i.e., it will not involve physical or
psychological harm or damage to human beings, or to the natural or
social environment of which they are a part). We will discuss the
subject of ethics in detail in Chapter Three.
Research Questions should be clear

R Q. is the focus of
a research
investigation, it is
particularly
important that the
Q. be clear

What exactly is
being
investigated?
Examples of Research Questions


Example 1: “Is a
humanistic oriented
classroom effective?

May seem quite
clear, many
people may not be
sure exactly what
it means.
are not clear enough
If we ask, “What is a humanistic ally
oriented classroom?” We begin to
discover that it is not as easy as we
might have thought to describe its
essential characteristics.

Another term in this question is also ambiguous.
What does the term “effective” mean?
Example 2:

“How do
teachers feel
about special
classes for the
educationally
handicapped?

The first term that
needs clarification is
“teachers.”

The phrase “feel
about” is also
ambiguous.
The terms

“special classes”
and ‘educationally
handicapped” also
need to be clarified


.
An example of a
legal definition of an
educationally
handicapped student
is:

A minor, by reason of
marked learning or
behavioral disorders,
is unable to adapt to
a normal classroom
situation.
The Terms (cont.)


The disorder must be associated with a
neurological handicap or an emotional
disturbance and must not be due to mental
retardation, cultural deprivation, or a
foreign language problems.
Ambiguous words, such as “marked
leaning disorders,” which lend themselves
to a wide variety of interpretations.
The Terms (cont.)

As we begin to think about these (or other)
questions, it appears that terms which
seemed at first glance to be words or
phrases that every one would easily
understand are really quite complex and
far more difficult to define than we might
originally have thought.
What do such terms mean?


Consider such term as “core curriculum,”
“activity learning,” What do such terms
mean?
If you were to ask a sample of five or six
teachers or administrators that you
know, probably would get several
different definitions. Such ambiguity
represents a problem to investigators of a
research question.
be specific & define precisely


Researchers have no
choice but to be
specific about the
terms used in a
research question, to
define precisely what
is to be studied.
In making this effort,

researchers gain a
clear picture of how
to proceed with an
investigation, and, in
fact, sometimes
decide to change the
very nature of the
research.
Defining terms: Three ways to clarify
important terms in a research question


How, then, might the clarity of a
research question be improved?
1. A constitutive definition – that is, to
use what is often referred to as the
dictionary approach. Researchers
simply use other words to say more
clearly what is meant.
defined as:


, the term “humanistic classroom” might be
defined as:
A classroom in which(1) the needs and
interests of students have the highest
priority; (2) students work on their own for
a considerable amount of time in each
class period; and (3) the teacher acts as a
guide and a resource person rather than
an informant.
the dictionary approach


Notice, however,
that this definition is
still somewhat
unclear, the term
“humanistic” are
themselves
ambiguous.
What does it
mean to say that
“the needs and
interests of
students have the
highest priority”
or that “ students
work on their
own” And so on.
the dictionary approach (cont’)


Further clarification is needed.
As we have seen this approach has its own
limitations
2. A second possibility is to
clarify by example

Researchers might
think of a few
humanistic
classrooms with
which they are
familiar and then try
to describe as fully
as possible what
happens in these
classrooms.

We’d suggest that
people observe
such classrooms
to see for
themselves how
they differ from
other classrooms.
to clarify by example

This approach also has its problems,
however, since our descriptions may
still not be clear to others as they
would like.
A third method of clarification is to define
important terms operationally

Operationally
definitions require
that researchers
specify the actions or
operations necessary
to measure or
identify the term.

Defining terms
operationally is a
helpful way to clarify
their meaning.
Operational
definitions are useful
tools and should be
mastered by all
students of research.
Operationally definitions


Remember that the operations or activities
necessary to measure to identify the term
must be specified.
Which of the following possible definitions
of the term “motivated to learn
mathematics” do you think are
operational?
Which of the Following Definitions Are Operational?
Page 34
1. As shown by enthusiasm in class
2. As judged by the student’s math teacher using a rating scale she
developed
3. As measured by the “Math Interest” questionnaire
4. As shown by attention to math tasks in class
5. As reflected by achievement in mathematics
6. As indicated by records showing enrollment in mathematics
electives
7. As shown by effort expended in class
8. As demonstrated by number of optional assignments completed
9. As demonstrated by reading math books outside class
10. As observed by teacher aides using the “Mathematics Interest”
observation record
7
specifying operational definitions

In addition to their value in helping
reader understand how researchers
actually obtain the information they
need, specifying operational
definitions is often helpful in clarifying
terms.
operational definitions

Thinking about how to measure “job
satisfaction,” for example, is likely to force
a researcher to clarify, in her own mind,
what she means by the term (For everyday
examples of times when operational
definitions are needed)
Some Times When Operational Definitions
Would Be Helpful
Figure 2.2
8
Relationships


R. Qs often (but not
always)suggest a
relationship of some
sort to be investigated.
RLTS Means that two
qualities or
characteristics are tied
together or connected
in some way


Are motivation and
learning related? If
so how?
A principal’s
administrative
policies and faculty
morale?
Relationships (cont.)


IT is important to understand how the term
“relationship” is used in research, since the
term has other meanings in everyday life.
When researchers use the term RLTS, they
are not referring to the nature or quality of an
association between people, for example.
Look at the next slide
Illustration of Relationship Between Voter
Gender and Party Affiliation
Figure 2.3
9
Relationships (cont.)


There is a strong RLTS between the two
factors shown in group B.
We can express the RLTS in group B by
saying that males tend to be Republications
while females tend to be democrats. We can
also express this RLTS in terms of a
prediction. Should another female joint group
B. She would be a democrat since 14 of the
previous 16 females are Democrats.
Relationships (cont.)


Sometimes researchers are interested
only in obtaining descriptive information
to find out how people think or feel or
to describe how they behave in a
particular situation.
Other times the intent is to describe a
particular program or activity.
Relational and Nonrelational questions



There are two basic kinds of quantitative
research questions:
Relational and non-relational.
Non-relational questions simply ask for a
report on the state of some variable.
Example of non-relational questions follow:
Non-relational questions
(cont)

 What methods of
counseling are
employed at the
University if New
Mexico Student
Health Center?


 What is the
average Graduate
Record examination
(GRE) score of 1997
college graduates?
 What percentage
of students drops out
before high-school
graduation?
Non-relational questions (cont)

Do you see that each
of these questions
asks what the value
of the variable
counseling method
are at a particular
center.
The second
question asks
about the
average value
of the variable
GRE score for
certain group of
students.
Non-relational questions (cont)

The third asks what proportion of
students has the value dropout,
as opposed to non-dropout, of
the variable dropout status.
Relational questions

Relational questions ask about the
relationship between two (or more)
variables. Examples of relational questions
follow:
Relational questions (cont)


 Is directive
counseling more
successful than
nondirective?
 Do people have
higher GRE scores
earn more money?


 Does a higher percentage
of culturally diverse that of
Anglo children drop out of
high school?
Do you see that each of these
questions asks about the
relationship between two
variables?
Relational questions (cont)

Relational research
has the potential for
yielding
understanding of
cause and effect.
Understanding cause
and effect is one of
the highest goals of
science.
Relational questions (cont)

When you have identified the research question in a
quantitative research report, ask yourself whether the
question involves at least two variables and whether
there is the suggestion of a relationship, often causal
between these two variables. If so, the research is
relational.
Relational and Nonrelational questions

You must, however, exercise some caution
in applying this rule. It is possible for nonrelational research to involve two or more
variables – for example, what are the
heights and weights of certain people?
Unless it is clear that the researcher will be
trying to relate the two variables, these are
simply tow separate non- relational
questions in one study.
A Single Research Question Can
Suggest Several Hypotheses
Figure 4.4
20
Directional vs. Nondirectional Hypotheses
Figure 4.5
21
Hypotheses

Relational
research
questions are
usually stated as
hypotheses..

A hypothesis is a
prediction about
the relationship
between two or
more variables
Hypotheses


 people with high
GRE scores will have
higher incomes.
 There will be no
difference in the
dropout rates of
culturally diverse and
Angle children.

Researchers restate their
relational research
questions as hypotheses
because hypotheses can be
subjected to empirical test.
We can change the
question to a prediction
and then find out whether
or not the prediction is
empirically confirmed
Research Involves the Study of Relationships
Between Variables
Page 59
a. Two quantitative variables
•
•
•
•
Age and amount of interest in school
Reading achievement and mathematics achievement
Classroom humanism and student motivation
Amount of time watching television and aggressiveness of behavior
b. One categorical and one quantitative variable
•
•
•
•
Method used to teach reading and reaching achievement
Counseling approach and level of anxiety
Nationality and liking for school
Student gender and amount of praise given by teachers
c. Two categorical variables
•
•
•
•
18
Ethnicity and father’s occupation
Gender of teacher and subject taught
Administrative style and college major
Religious affiliation and political party membership
Definition of a Variable
A Variable
(A Characteristic or Attribute)
Can be
Measured
(Can be assessed
on an instrument
and recorded on
an instrument)
and
Varies
(Can assume
different values or
scores for
different
individuals)
Variables and Constructs
A Variable is an attribute or
characteristic stated in a specific or
applied way
 A Construct is an attribute or
characteristic
expressed
in
an
abstract,
Construct
Student Achievement
general way.

Variable
Grade Point Average
How Many Variables Can You Identify?
Page 54
15
Operational definitions

Whether the research process is a valid one
for answering the questions the research
posed. If the process is valid, then the
answer should be valid
Measurement validity


Two basic kinds of
validity – internal and
external.
Internal validity refers
to whether the
research process yields
a result that is valid in
the research context –

that is, whether the
answer to the research
question is valid for
the people on whom
the research was done,
at the time the
research was done, in
the place the research
was done.
External validity

External validity refers to whether the
answer to the research question is valid in a
larger context – for other people , at other
times, in other places.
Internal validity

Internal validity has two components:
measurement validity and validity of causal
argument
Measuring Variable Values

When a quantitative
researcher has decided
on the variables she
wishes to study, a
method must be found
for measuring the
variables –

that is, for determining
the value of each
variable for each of
the subjects that will
be studied.
Measuring Variable Values
(cont.)

For example, if gender is one of the
variables of interest, researcher must decide
on a method for determining whether each
subject is male or female. Gender may also
be measured by checking records; school
records
Measuring Variable Values
(cont.)

Similarly, intelligence may be measured in many
ways. There are a number of standardized tests
that are considered to be the tests of intelligence;
any of these might be used. Intelligence could
also be measured by asking students’ teachers;
teachers might, for example, be asked to assign
each students in their classes a value of above
average, average, or below average in intelligence.
Operational Definitions

This process of
deciding how to
measure a variable
must be ultimately
result in what is called
operational definition.

An operational
definition of a variable
specifies the
operations that will be
performed to measure
the variable.
Operational Definitions (cont.)

Operational definitions are thus very
precise; they give such complete
information about how a variable is
measured that other researchers can use
them to replicate the method of
measurement for a given variable
Categorical and Continuous
Scores


A categorical score is a value of a variable
assigned by the researcher into a small
number of categories. (e.g. Gender)
A continuous variable is the value of a
variable assigned by the researcher to a point
along a continuum of scores, from low to
high. (e.g. Age)
Illustration of Quantitative Compared
with Categorical Variables
Figure 4.1
16
Categorical Variables
Figure 4.2
17
Families of Variables

Independent Variable: An attribute
or characteristic that influences or
effects an outcome of the independent
variable.




Treatment Variable
Measured Variable
Control Variables
Moderating Variables
Independent versus Dependent
Variables.


Often relational research is an attempt to
demonstrate not just a relationship but a causal
relationship. The existence of a relationship
between the method of counseling employed and
the outcome of counseling suggests that the
method of counseling employed is one of the
causes of the outcome of counseling.
Independent versus Dependent
Variables(cont.)


Effects depend on causes; the values of
effect variables depend on the values of
causal variables.
It is important for you to think that what
is a dependent variable in one study may be
an independent variable in another.
Causes Versus Association

Not all relational research is about causal
relationships. There are non-causal
relationships, as well as relationships in
which cause is in doubt; the term
association or correlation is often used to
refer to such relationships.
Causes Versus Association
(cont.)

Distinguishing between cause and
association can be a serious problem in
research. Often our research methods can
tell us only that variables are associated;
they cannot tell us whether the relationship
is causal.
Proxy Variables


The use of proxy variables is a special case
of associational research
Proxy variables can be useful when true
causal variables are not well understood or
are difficult to measure.
Predictor and Criterion
Variables

Some educational research
is explicitly designed to
provide information about
non-causal associations
between variables
College entrance
examinations and gradepoint averages are a good
example.

When research is done
as a basis for making
such predictions,
research often use
special terms for their
variables.
Predictor and Criterion
Variables (cont.)

What would usually be termed independent
variables are instead labeled predictor variables,
and what would usually be termed dependent
variables are instead criterion variables. When
researchers use these terms they are explicitly
saying that any relationship between variables is
thought to be not causal but simply associational
Families of Variables


Intervening Variables (Mediating
Variables): An attribute or
characteristic that “stands between” the
dependent and independent variables.
Dependent Variables: An attribute
or characteristic influenced by the
independent variable.
Families of Variables

Confounding Variables (Spurious
Variables): Attributes or
characteristics that the researcher
cannot directly measure because their
effects cannot be easily separated from
the other variables, even though they
may influence the relationship between
the independent and the independent
variable.
The Family of Variables in
Quantitative Studies
Probable
Cause
Independent
Variables
•Treatment
•Measured
Effect
Intervening
Variables
Dependent
Variables
Control
Variables
Moderating
Variables
Confounding
Variables
Examples of Extraneous Variables
Figure 4.3
19
Intervening Variables “Stand Between”
Independent and Dependent Variables
Step 1
Independent
Variable
Dependent
Variable
Example Convenient office hours
Student seeks help
from faculty
for students
Step 2
Example
Step 3
Example
Independent
Variable
Variable
Convenient office hours
for students
Independent
Variable
Convenient office hours
for students
Intervening
Variable
Student becomes willing
to take risks
Intervening
Variable
Student becomes willing
to take risks
Dependent
Variable
Student seeks help
from faculty
Theories as Bridges Between
Independent and Dependent
Variables
Independent
Variables
Dependent
Variables
Different Types of
Explanations in Quantitative
Research
Extensive Tests by
other researchers
Broad
Abstractions
As a formal theory that is expressed by connected
hypotheses and variables identified by authors
As a conceptual framework often expressed as a
visual model by other authors for relationship
As a theoretical rationale posed by other authors
based on studies for relationship
No Test
As explanation posed by the author as a hunch for
why the independent variable relates to the
dependent variable
Narrow
Application
Whether Variables Prove
Probable Cause


Probable causation: The researchers attempt
to establish a likely cause/effect relationship
between variables rather than prove the
relationship.
Control is vital: Control means that the
researcher attempts to study all factors that
might help explain the relationship between
an independent and dependent variable.
Four Types of Probable
Causality
X = independent variable
Y = dependent variable
1. Time: Close in time, not distant
Y
X-Y, not X
2. Space: Close in distance, not distant
X-Y, not X
Y
3. Variation: One goes up, the other down
X
Y, not X Y
3. Multiple Causes: Multiple independent variables
influence the dependent variable
X
X
Y
X
Differences between quantitative and qualitative
purpose statements and research questions
Quantitative - more
Qualitative - more
closed
open-ended
1. Probable cause/Effect (“Why did it
happen?”)
2. Use of theories (Why did it happen
in view of an explanation or
theory?”
3. Assessing differences and magnitude
“How much happened?”
“How many times did it happen?
What were the differences among
groups in what happened?
1. Descriptive (“What happened?”)
2. Interpretive (“What was the
meaning to people of what
happened?”)
3. Process-oriented (“What
happened over time?”)
How researchers explain or predict variables
versus exploring or understanding a Central
Phenomenon
Quantitative
Explaining or
Predicting Variables
X
Y
Qualitative
Understanding or
exploring a
Central
Phenomenon
Y
The independent variable (X)
influences a dependent
variable (Y)
In-depth understanding of Y;
external forces shape and are
shaped by Y
Qualitative Research
Considerations




More open-ended
The direction of the study is focused on how
to best learn from the participants
The focus of the research is around a
Central Phenomenon which is an issue or a
process the researcher would like to study.
Qualitative research is built on an emerging
design
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