AP Psychology Semester Review Unit 2

Independent Variable

variable manipulated by the experiment

Dependent Variable

variable measured by the independent variable

Control group

group used as comparison & no treatment (placebo group)

Experimental group

group manipulated by independent variable

Random assignment

each participant has an equal chance of being placed into any group

Random selection

participants randomly chosen from the target population

Inferential statistics

using data to generalize & infer about a population

Operational Definitions

exact procedures used to produce specific results

Hawthorne Effect

when people change their behavior because they know they’re being observed

Correlational Studies

relationship between 2 variables; no cause/effect relationship

Correlational coefficient

a number to show degree of a relationship (-1.0 to +1.0)

Naturalistic observation

studying a subject in their natural environment

Experimental studies

independent variables directly manipulated/effects on dependent variables are examined (ex: lab study or field study)

Longitudinal studies

studies a group of participants over a long period of time

cross sectional studies

studies a population that varies between multiple types

case study

using several methods; a more in-depth approach to study a person or issue

APA: American Psychological Association

creates ethical guidelines for human and animal research

IRB: Institutional Review Board

reviews research proposals for ethical violations and/or procedural errors

APA guidelines for humans

• no coercion

• informed consent

• anonymity or confidentiality

• risk

• debriefing

APA guidelines for animals

• must have clear scientific purpose

• must have specific important question

• must care for/house in a humane way

• must acquire them legally

• must design experimental procedures to employ least amount of suffering possible

• animals chosen should be best fit to answer the question

Positive correlation

As one variable increases so does the other variable (upward line)

Negative correlation

As one variable increases the other variable decreases (downward line)

No correlation

There is no relationship between the two variables

Statistical significance