Chapter 6: Causation and Experimental Design

Question 1

Causal effect

Answer 1

The finding that change in one variable leads to change in another variable (other things being equal.)

Ex. Individuals arrested for domestic assault tend to commit fewer subsequent assaults than similar individuals who are accused in the same circumstances but are not arrested

Question 2

Ceteris paribus

Answer 2

Latin phrase meaning “other things being equal.”

Question 3

Association

Answer 3

A criterion for establishing a causal relationship between two variables. Variation in one variable is empirically related to variation in another variable

Question 4

Time order

Answer 4

A criterion for establishing a causal relationship between two variables. The variation in the presumed cause (the independent variable) must occur before the variation in the presumed effect (the dependent variable).

Question 5

Nonspuriousness

Answer 5

A criterion for establishing a causal relation between two variables; when a relationship between two variables is not caused by a variation in a third variable

Question 6

Spurious

Answer 6

Nature of a presumed relationship between two variables that actually results from variation in a third variable

Question 7

Mechanism

Answer 7

A discernible process that creates a causal connection between two variables

Question 8

Context

Answer 8

The larger set of interrelated circumstances in which a particular outcome should be understood

Question 9

True experiment

Answer 9

Experiment in which subjects are assigned randomly to an experimental group that receives a treatment or other manipulation of the independent variable an a comparison group that does not receive the treatment or receives some other manipulation. Outcomes are measured in a posttest.

Question 10

Comparison group

Answer 10

In an experiment, groups that have been exposed to different treatments or values of the independent variable (e.g., a control group an an experimental group).

Question 11

Experimental group

Answer 11

In an experiment, the group of subjects that receives the treatment or experimental manipulation.

Question 12

Control group

Answer 12

A comparison group that receives no treatment

Question 13

R, O, and X

Answer 13

R = random assignment
O = Observation (prestest [O1] or posttest [O2])
X = Experimental treatment

Question 14

Posttest

Answer 14

In experimental research, the measurement of an outcome (dependent) variable after an experimental intervention or after a presumed independent variable has changed for some other reason. The posttest is exactly the same “test” as the pretest, but it is administered at a different time.

Question 15

Pretest

Answer 15

In experimental research, the measurement of an outcome (dependent) variable before an experimental intervention or change in a presumed independent variable for some other reason. The pretest is exactly the same “test” as the posttest, but it is administered at a different time

Question 16

Random assignment (randomization)

Answer 16

A procedure by which each experimental subject is placed in a group randomly

Question 17

Matching

Answer 17

A procedure for equating the characteristics of individuals in different comparison groups in an experiment. Matching can be done on either an individual or an aggregate basis. For individual matching, individuals who are similar in key characteristics are paired before assignment, and then the two members of each pair are assigned to the two groups. For aggregate matching, groups chosen for comparison are similar in distribution of key characteristics.

Question 18

Quasi-experimental design

Answer 18

A research design in which there is a comparison group that is comparable to the experimental group in critical ways but subjects are not randomly assigned to the comparison and experimental groups

Question 19

Nonequivalent control group design

Answer 19

A quasi-experimental design in which there are experimental and comparison groups that are designated before the treatment occurs but are not created by random assignment

Question 20

Before-and-after design

Answer 20

A quasi-experimental design consisting of several before-and-after treatment comparisons involving the same variables but no comparison group

Question 21

Ex post facto control group design

Answer 21

A nonexperimental design in which comparison groups are selected after the treatment, program, or other variation in the independent variable has occured

Question 22

Multiple group before-and-after design

Answer 22

A type of quasi-experimental design in which several before-and-after comparisons are made involving the same independent and dependent variables but different groups

Question 23

Repeated measures panel design

Answer 23

A quasi-experimental design consisting of several pretest and posttest observations of the same group

Question 24

Time series design

Answer 24

A quasi-experimental design consisting of many pretest and posttest observations of the same group

Question 25

11 Threats to Internal Validity

Answer 25

1. Selection
2. Mortality
3. Instrument Decay
4. Testing
5. Maturation
6. Regression
7. History
8. Contamination
9. Experimenter Expectation
10. Placebo Effect
11. Hawthorne Effect

Question 26

Selection Bias

Answer 26

A source of internal (causal) invalidity that occurs when characteristics of experimental and comparison group subjects differ in any way that influences the outcome

Question 27

Differential attrition (mortality)

Answer 27

A problem that occurs in experiments when comparison groups become different because subjects in one group are more likely to drop out for various reasons compared with subjects in the other group(s).

Question 28

Instrument Decay

Answer 28

The deterioration over time of a measurement instrument, resulting in increasingly inaccurate results

Question 29

Endogenous change

Answer 29

A source of causal invalidity that occurs when natural developments or changes in the subjects (independent of the experimental treatment itself) account for some of all the observed change from the pretest to the posttest.

Question 30

Regression effect

Answer 30

A source of causal invalidity that occurs when subjects chosen because of their extreme scores on a dependent variable become less extreme on a posttest as a result of mathematically necessity, rather than the treatment.

Question 31

History effect (affect of external events)

Answer 31

Events external to the study that influences posttest scores, resulting in causal invalidity

Question 32

Contamination

Answer 32

A source of causal invalidity that occurs when either the experimental or the comparison group is aware of the other group and is influenced in the posttest as a result

Question 33

Compensatory rivalry (John Henry effect)

Answer 33

A type of contamination in experiment and quasi-experimental designs that occurs when control group members are aware that they are being denied the treatment and modify their efforts by way of compensation

Question 34

Demoralization

Answer 34

A type of contamination in experimental and quasi-experimental designs that occurs when control group members feel that they have been left out of some valuable treatment, performing worse than expected as a result

Question 35

Treatment misidentification

Answer 35

A problem that occurs in an experiment when not the treatment itself, but rather some unknown or unidentified intervening process, is causing the outcome

Question 36

Expectancies of experiment staff (self-fulfilling prophecy)

Answer 36

A source of treatment misidentification in experiments and quasi-experiments that occurs when change among experimental subjects results from the positive expectancies of the staff who are delivering the treatment, rather than to the treatment itself.

Question 37

Double-blind procedure

Answer 37

An experimental method in which neither the subjects nor the staff delivering experimental treatments know which subjects are getting the treatment

Question 38

Placebo effect

Answer 38

A source of treatment misidentification that can occur when subjects receive a treatment that they consider likely to be beneficial and improve as a result of that expectation rather than the treatment itself.

Question 39

Hawthorne effect

Answer 39

A type of contamination in experimental and quasi-experimental designs that occurs when members of the treatment group change relative to the dependent variable because their participation in the study makes them feel special

Question 40

Process analysis

Answer 40

A research design in which periodic measures are taken to determine whether a treatment is being delivered as planned, usually in a field experiment

Question 41

Field experiment

Answer 41

An experimental study conducted in a real-world setting

Question 42

Solomon Four-Group Design Testing the Interaction of Pretesting and Treatment

Answer 42

R O1 X O2
R 01 O2
R X O2
R O2

R = random assignment
O = observation (pretest or posttest)
X = experimental treatment

Question 43

Distribution of benefits

Answer 43

An ethical issue about how much researchers can influence the benefits subjects receive as part of the treatment being studied in a field experiment