Research Methods in Psychology

Hypothesis

Statements about the prediction of the results that can be verified or disproved.

Sampling

The process of selecting a representative group from the population under study.

Random Sampling

When every person in the target population has an equal chance of being selected. Ex. Picking names out of a hat.

Variables (Ind. and Dependent variables).

Independent: The variable that the experimenter manipulates/changes. It is what impacts the dependent variable.

Dependent: What is being measured/the results

Operational Definition

A description of procedures, actions, or processes used in a study. (allows study to be replicated by others).

Experiments

• Isolates cause and effect

• tries to investigate hypothesis

• Involves ind. and dependent variables

Case Study

In-depth investigations of a person, group, event, or community. Can be longitudinal.

Correlational Studies

A measure of the extent to which two variables are related. One of the variables can be regarded as the predictor variable with the other one as the outcome variable. Correlational studies typically involve obtaining two different measures from a group of participants, and then assessing the degree of association between the measures. 

• If an increase in one variable tends to be associated with an increase in the other, then this is known as a positive correlation.

• If an increase in one variable tends to be associated with a decrease in the other, then this is known as a negative correlation.

• A zero correlation occurs when there is no relationship between variables.

• Correlation DOES NOT always prove causation.

Observations

Behavior is being observed

Meta-Analysis

Statistical procedure used to combine and synthesize findings from multiple independent studies to estimate the avg. effect size for a particular research question.