How to identify Variables and Write Research Hypotheses

Doing research for the Social Science. How to identify independent and dependent variables. How to write research hypotheses

2. Variables are a class of outcomes that can take on more
than one value. Eg.include: Height, Weight, Social
class, Color
Variables can therefore be further divided into specific
categories or attributes
Eg.Social Class: Underclass Lower Class, Working
Class, Middle Class, Upper Class
The more precisely a variable is measured, the more
useful the measurement is

7. Independent
Dependent
Represents the
treatments or conditions
that the researcher has
either direct or indirect
control over to test their
effects on a particular
outcome.
At least two different
values of the
independent variable
must be present
reflects the outcomes of a
research study.

8. The longer you spend on a task the better the
results.
People who attend church regularly are more
likely to oppose abortion
Educated women are likely to have fewer
children

9. Type of
Variable
Definition Other Terms You
Might See
Dependent
A variable that is measured to see whether the treatment or
manipulation of the independent variable had an effect
•Outcome variable
•Results variable
•Criterion variable
Independent
A variable that is manipulated to examine its impact on a
dependent variable
•Treatment
•Factor
•Predictor variable
Control
A variable that is related to the dependent variable, the
influence of which needs to be removed
•Restricting variable
Extraneous
A variable that is related to the dependent variable or
independent variable that is not part of the experiment
•Threatening variable
Moderator
A variable that is related to the dependent variable or
independent variable and has an impact on the dependent
variable
•Interacting variable

10. “An educated guess”

11. Reflects the general problem under study
Restates the general problem in a form
that is precise enough to allow testing
Two types:
❑Null Hypothesis
❑Research Hypothesis

12. States that there is no relationship between the
independent and dependent variables under
study : Ho = the symbol for the null hypothesis
❑There will be no difference in the average score of ninth graders and
the average score of twelfth graders on the ABC memory test.
❑There is no relationship between personality type and job success.
❑There is no difference in voting patterns as a function of political
party.

13. A starting point for analysis
Accepted as true absent other information
Assumes that chance caused any observed
differences
Provides a benchmark for comparison

14. Whereas a null hypothesis is a statement of no relationship
between variables, a research hypothesis is a definite
statement of the relationship between two variables.
Nondirectional Research Hypothesis
Groups are different, but direction is not specified
Teachers who are more knowledgeable about HIV/AIDS treat their
students differently than those who do not know as much.
Directional Research Hypothesis
Groups are different, and direction is specified
Teachers who are more knowledgeable about HIV/AIDS treat their
students who are infected better than those who do not know as much.

15. Is stated in declarative form
Posits a relationship between variables
Reflects theory or literature
Is brief and to the point
Is testable