Chapter 2 definitions

Question 1

Theory

Answer 1

• a general statement about the relationship between constructs/events.
• must be parsimonious
• must generate a testable hypothesis

Question 2

Hypothesis

Answer 2

-formal prediction about the relationship between two or more variables which is logically derived from the theory

Question 3

Independent Variable (aka treatment variable)

Answer 3

-determines how the groups in the experiment are divided

Question 4

Dependent Variable

Answer 4

-(aka outcome variable or variable to be measured) is measured by the investigator and is used to compare the experimental groups.

Question 5

Interaction

Answer 5

-how one independent variable affects the dependent variable depends on the other independent variable.

Question 6

Manipulated Independent Variable

Answer 6

• investigator begins with a large number of participants and assigns them to experimental groups

Question 7

Nonmanipulated Independent Variable (aka subjects variable)

Answer 7

Exists without the researcher’s intervention (ie. Participants are separated according to Character or physical traits, birth order etc.)

• participants are not randomly assigned
• problem with nonmanipulated variable is that it cannot be assumed that the participants are identical on average in the beginning because they are not randomly assigned
• cause/effect relationship difficult to determine in nonmanipulated variables

Question 8

3 elements of an experiment

Answer 8

1) generate a theory
2) make a hypothesis
3) collect data to support hypothesis

Question 9

Replication

Answer 9

-examine participant populations different from those in the original research so that it can be determined if these results can be generalized to a larger population

Question 10

File Drawer Problem

Answer 10

-often only “significant results” are published so we do not know where we went wrong on non-significant experiments

Question 11

Case Study Method

Answer 11

• in-depth evaluation of a single individual (or sometimes a few individuals)
• often involves a psychotherapy client suffering from a problem that the researcher is interested in
• ○ Client’s history, current behavior and changes in behavior over the investigation are recorded
• often involves descriptive data

Question 12

limitations of case study (3)

Answer 12

• cannot generalize results from a single person to a large population
• issues determining cause/effect relationships
• investigators subjective judgements can influence results

Question 13

Pros of case study method (2)

Answer 13

• appropriate when investigating a rare case (ie. multiple personalities)
• Appropriate when it can be argued that the individual being studied is no different from people on the dimension of interest (ie. Studying participants with a severed corpus collapsum; it can be argued that these participants have a “normal” brain and that these results can be compared)

Question 14

statistical significance

Answer 14

• if the difference was large enough that in all likelihood it was not caused by chance
• traditionally a 0.5 significance level is used (ie. difference between scores is so large that it would occur less than 5% of the time by chance)

Question 15

Correlation coefficient

Answer 15

• statistical test used to understand the relationship between two measures
• Need to examine reliability and validity before using any standardized test.

Question 16

test-retest reliability coefficient

Answer 16

-researchers administer the test to a large number of people; this test is then re-administered to the same people some time later. The scores from the first administration are correlated with those from the second. A high positive correlation coefficient (ie. 0.90) indicates good consistency over time.

Question 17

internal consistency

Answer 17

-Test is internally consistent when all the items on the test measure the same thing; high internal consistency coefficient can indicate that most items are measuring the same concept.

Question 18

Face Validity

Answer 18

-do the test items appear to measure what they are supposed to measure.

Question 19

Congruent validity (convergent validity)

Answer 19

-extent to which scores from the test correlate with other measures of the same construct; if two tests measure the same thing then the scores should highly correlate

Question 20

Discriminant validity

Answer 20

-refers to the extent to which a test score does not correlate with the scores of theoretically unrelated measures.

Question 21

Behavioral validation

Answer 21

-it is important that test scores predict relevant behavior as participants may behaviorally respond as they think they would act/how they wish they would act.