Topic 5

Question 1

Define experiment

Answer 1

Systematic research study in which investigators directly vary some factors

Question 2

Method of agreement

Answer 2

If X is regularly followed by Y, the X is sufficient for Y

• X could be a cause of Y
• if X, then Y

Question 3

Method of difference

Answer 3

Y does not occur when X does not occur
- X is necessary for Y to occur
- if not X, then not Y

Question 4

Independent variable

Answer 4

The factor of interest in a study
- studying to see if it influences behaviour
- must include +2 levels for comparison

Question 5

Field experiment

Answer 5

Research and experiments done outside of a lab in a more realistic field environment

Question 6

Types of independent variables

Answer 6

Situational - altering the environment or situation between participant groups
Task - giving participant groups different tasks
Instructional - telling participant groups to perform tasks given different instructions

Question 7

Control group

Answer 7

The group of participants with no experimental treatment

Question 8

Extraneous variables

Answer 8

Variables that aren’t of interest but might influence the behaviour of participants if not controlled

Question 9

Confound

Answer 9

Any extraneous variable that results to a change in the independent variable

Effects cannot be distinguished from IV

Question 10

Dependent variable

Answer 10

Behaviours that are measured outcomes of the experiment
- the result of the IV changing a factor

Question 11

Ceiling vs floor effect

Answer 11

Results are all either too high or too low to determine a difference between them

Prevented by assigning moderately difficult tasks determined through previous testing

Question 12

Subject variables

Answer 12

Differences between groups other than the IV trying to be studied

Question 13

Conclusions with IV vs. SV

Answer 13

IV
- no confounds
- IV causes DV

SV
- groups differ in many ways
- IV may not cause DV

Question 14

Statistical conclusion validity

Answer 14

The extent to which the researcher uses statistics to properly draw appropriate conclusions from statistical analysis
- reduced by wrong analysis, violated assumptions, not reporting analyses, unreliable measures

Question 15

Construct validity

Answer 15

Whether a test truly measures a construct or not

Question 16

External validity

Answer 16

The degree to which results can be generalized beyond the context of the experiment
- other populations
- other environments
- other times
- not a major concern with specific research
- low external validity does not mean invalid research

Question 17

Ecological validity

Answer 17

Relevance to the cognitive daily activities of people trying to adapt to their environments

Question 18

Internal validity

Answer 18

The degree to which an experiment is methodologically sound and confound free
- DV is related to the IV
- valid operational definitions

Question 19

Threats to internal validity

Answer 19

• reduced by extraneous factors and comparison between nonequivalent groups
  -studies extending over time (pretest and posttest to reduce threat)
• history threatens with major events between pre and posttests
• general maturation causes behavioural changes
• regression to the mean
• testing (pretests effect posttest scores)
• instrumentation

All above can be reduced with control groups

-subject selection effect (subjects choose their groups)
- attrition (participants leaving or not showing up for the second half of an experiment)