Threats to External Validity

Question 1

A study has ____________________ validity when its results can be generalized to other people, settings, and conditions.

Answer 1

External.

Question 2

A high degree of ________________ validity does not guarantee ___________ validity.

Answer 2

• Internal
• External

Question 3

Threat to External Validity - ____________________: The administration of a pretest can “sensitize” subjects to the purpose of the research study and thereby alter their reaction to the IV. Use of the Solomon Four-Group Design can be used to control for this by allowing the investigator to measure the impact of pretesting on both the external and internal validity of a research study.

Answer 3

Interaction Between Testing and Treatment.

Question 4

Threat to External Validity - ____________________: Subjects included in a research study can have characteristics that make them respond to the independent variable in a particular way.

Answer 4

Interaction Between Selection and Treatment.

Question 5

Threat to External Validity - ____________________: Research participants may respond to an independent variable in a particular way simply because they know their behavior is being observed; these can be due to:

• Evaluative apprehension
• Demand characteristics
• Experimenter expectancy

Answer 5

Reactivity (Reactive Arrangements).

Question 6

In a ______________ study, the participants don’t know which group they’ve been assigned to. In a _______________ study, neither participants nor investigators know which group participants have been assigned to.

Answer 6

• Single-blind
• Double-blind

Question 7

Threat to External Validity - ____________________: When a study involves exposing each subject to two or more levels of an independent variable (i.e., when the study utilizes a within-subjects design), effects of one level of the IV can be affected by previous exposure to another level.

Answer 7

Multiple Treatment Interference (Order Effects, Carryover Effects).

Question 8

Multiple treatment interference can be controlled by using a ___________________ design, in which different subjects (or groups of subjects) receive he levels of the IV in a different order. The ________________ design is one type, that involves administering each level of the IV so that it appears the same number of times in each position (1st, 2nd, 3rd, etc.).

Answer 8

• Counterbalanced
• Latin Square