Chapter 8

Question 1

Characteristics of Experimental Research

Answer 1

The researcher decides on and carries out the specific interventions (or treatments) for one or more groups of subjects

The researcher controls extraneous variables so that they don’t pose alternative explanations for the results of the experiment

The researcher controls subject variables (characteristics) so that they are equivalent in different groups

Question 2

a

Answer 2

1

Question 3

b

Answer 3

2

Question 4

C

Answer 4

3

Question 5

D

Answer 5

4

Question 6

a

Answer 6

1

Question 7

b

Answer 7

2

Question 8

C

Answer 8

3

Question 9

D

Answer 9

4

Question 10

Extraneous variables can be controlled

Answer 10

by eliminating them or by keep them constant

Question 11

Internal Validity

Answer 11

The extent to which the outcomes of an experiment can be attributed to the experimental conditions, and not to other extraneous or confounding variables

Question 12

When alternative explanations of the findings exist, we say that there are threats to _______________________.

Answer 12

the internal validity of the study

Question 13

For threats to internal validity to be “plausible” two conditions must be met: __________________ and ____________________.

Answer 13

The factor must influence the dependent variable

The factor must be different in amount or intensity across levels of the independent variable

Question 14

History

Answer 14

Threat from uncontrolled events that affect the dependent variable

Question 15

Statistical Regression

Answer 15

Threat from change of extreme scores to those closer to the mean. Can be controlled through the use of an equally extreme control group

Question 16

External History

Answer 16

Something that happened during the intervention outside the context of the study

Question 17

Selection (Subject Characteristics)

Answer 17

Threat from the characteristics of participants differing as a function of condition. This threat is much less likely when subjects have been randomly assigned to conditions.

Question 18

Maturation

Answer 18

Threat from changes in participants over time

Question 19

Pretesting

Answer 19

Threat from the effect of taking a pretest

Question 20

Instrumentation

Answer 20

Threat from the unreliability or changes in measurement

Question 21

Treatment Replication

Answer 21

Threat from insufficient replications of the treatment

Question 22

Subject Attrition (Mortality)

Answer 22

Threat from loss of subjects

Question 23

Statistical Regression

Answer 23

Threat from change of extreme scores to those closer to the mean. Can be controlled through the use of an equally extreme control group

Question 24

Diffusion of Treatment

Answer 24

Threat from treatment effect on one group affecting other groups

Question 25

External validity

Answer 25

refers to the extent to which the results of a study can be generalized to other subjects, interventions, procedures, and settings

Question 26

In the real world, there is generally a negative correlation between ___________________ and ___________; that is, studies strong in ___________ tend to be weak in _______________ and vice versa

Answer 26

internal validity and external validity | internal validity, external validity

Question 27

External validity can be used to refer to generalization across:

Answer 27

``` Subjects Situations or Contexts Time Interventions or Treatments Measures ```

Question 28

Single-Group Posttest-Only Design

Answer 28

A single group gets an intervention followed by a posttest No comparison is possible in this design

Question 29

Single-Group Pretest-Posttest Design

Answer 29

A single group gets a pretest, then an intervention, and finally a posttest Posttest scores can be compared to pretest scores

Question 30

Non-Equivalent-Groups Posttest Only Design

Answer 30

Two groups receive posttests, but only one receives the intervention Several groups receive posttests, but each receives a different intervention

Question 31

Non-Equivalent-Groups Pretest-Posttest Design

Answer 31

These designs mimic experimental designs, but lack random assignment of subject to groups, thereby being susceptible to selection or subject characteristic threats to internal validity

Question 32

Randomized-to-Groups Posttest-Only Designs

Answer 32

The randomized to groups designs are true experimental designs, because they use random assignment of subjects to groups A control group receives no intervention; a comparison group receives the “standard” intervention Random assignment produces groups that should be equivalent, as long as the N is large enough (generally at least 15 per group)

Question 33

Sometimes called a quasi-experimental design due to the lack of random assignment

Answer 33

Non-Equivalent-Groups Pretest-Posttest Design

Question 34

Subject Effects (Reactivity)

Answer 34

Threat from the effects of awareness of being a subject in a study. Examples are the Hawthorne effect, compensatory rivalry, resentful demoralization, and the novelty effect.

Question 35

Generalization over the type of and nature of measures used to represent the dependent variable require ________________.

Answer 35

studies to support such generalization.

Question 36

Interventions or Treatments | Generalization over different way of delivering a conceptually identical intervention requires _____________.

Answer 36

new studies.

Question 37

Generalization over time periods generally requires _______________.

Answer 37

additional studies at the new time periods.

Question 38

Generalization to new situations or contexts can be assessed through _________________________-.

Answer 38

sampling and statistics, but usually isn’t. Usually a logical argument is made by the experimenter.

Question 39

Ecological Validity

Answer 39

is the term used for generalizing from the laboratory to the real world.

Question 40

Generalization from the sample to sub-samples (e.g., different genders or ethnic groups) of the total population requires _____________.

Answer 40

additional statistical analyses

Question 41

Experimenter Effects

Answer 41

Threat from characteristics or expectations of the experimenter. Characteristics can include age, sex, race, status, hostility, authoritarianism, and physical appearance. Experimenter expectancy refers to deliberate or unintentional effects of bias on the part of the experimenter, which is reflected in differential treat of participants. These can be eliminated by running the experiment double-blind.

Question 42

Subject Effects (Reactivity)

Answer 42

Threat from the effects of awareness of being a subject in a study. Examples are the Hawthorne effect, compensatory rivalry, resentful demoralization, and the novelty effect.

Question 43

Factorial Designs

Answer 43

Studies that employ two of more IVs, or interventions, each of which may have multiple levels

Question 44

Field studies should check ________________.

Answer 44

intervention fidelity.

Question 45

Criteria for Evaluating Experimental Research

Answer 45

The primary purpose is to test causal hypotheses There should be direct control of the intervention The experimental design should be clearly identified The design should provide maximum control of extraneous/confounded variables The intervention should be described and implemented as planned The determination of n should be the same as independent replications The measure of the dependent variable must be sufficiently sensitive to capture the change caused by the intervention

Question 46

Single-Subject (Single Case) Designs

Answer 46

One or a few subjects are studied, rather than a large group The subject is measured multiple times prior to and after an intervention Behavior prior to the intervention is compared to behavior after the intervention to determine the effectiveness of the intervention

Question 47

Baseline

Answer 47

The period of time in which the target behavior is observed without the intervention

Question 48

Intervention

Answer 48

The period of time in which the target behavior is observed with the intervention

Question 49

A-B-A Design

Answer 49

Sometimes called a withdrawal design

Question 50

Characteristics of Single-Subject Research

Answer 50

``` Reliable Measurement Repeated Measurement Description of Conditions Baseline and Intervention Conditions Single-Variable Rule ```

Question 51

Multiple-Baseline Designs

Answer 51

Observations are made on one of the following: Several Subjects, Several Target Behaviors in a Single Subject, Different Situations (or Contexts) The onset of the intervention is offset in time for each of the: Subjects, Target Behaviors, Situations or Contexts

Question 52

Criteria for Evaluating Single-Subject Research

Answer 52

There should be reliable measurement of the target behavior The target behavior should be clearly defined Sufficient measures are needed to establish stability in behavior Procedures, subjects, and settings should be fully described A single, standardized intervention should be used Experimenter or observer effects should be controlled Results should be practically significant