AP Psychology - Unit 1, Module 6

Correlation

the extent to which two factors coincide with each other, and thus of how well either factor predicts the other

Correlation Coefficient

measure of how much correlation there is between two variables (Closer to negative 1 and positive 1 = high correlation)

Variable

anything that varies and can be measured

Scatterplots

graph of dots that represent the values of two variables; if there is a clear shape, then the slope shows the direction of relationship; random scatter indicates low correlation.

Illusory Correlation

perceiving a relationship that doesn’t exist; when we have an existing belief that there is a relationship, then we are likely to recall and nitpick instances to confirm belief

Regression Toward the Mean

statistical tendency for unusual events/scores to return to the average level over time

Experiment

manipulating factors of interest AND controlling external factors

Experimental Group

subjects exposed to treatment

Control Group

subjects not exposed to see effect

Single Blind Procedure

participants do not know if they are in the experimental or control group

Double Blind Procedure

research participants & research staff are ignorant (blind) if research participants have received the treatment; commonly used in drug evaluation studies

Placebo Effect

experimental results caused by expectations; any effect on behavior caused by the administration of a substance/condition that the recipient assumes is an active agent (ie. I take fake sleeping pill and I suddenly feel sleepier)

Independent Variable

factor that is being manipulated; variable whose effect is being studied

Dependent Variable

outcome that is measured, variable may change when the independent variable is manipulated

Confounding Variable

additional factors that could influence results (outside of the independent variable)

Validity

extent to which a test/experiment measures or predicts what it claims to

Random Sampling

a method of choosing participants that gives every person in a population an equal chance of being selected; ensures a representative sample

Random Assignment

a method of placing participants into experimental or control groups by chance; minimizes confounding variables