AP Psych Operational Definitions

Double-blind

A research design where neither the participants nor the researchers know who is receiving the treatment or the placebo, reducing bias in the results.

Ethical flaws

1. consent

2. deception

3. failure to protect participants' confidentiality and well-being.

confounding variable

something other than the independent variable that causes a change in the dependent variable

• ex: time → students are too tired in the morning or later in night

operational definition

something that assigns a NUMERICAL value to something abstract
a statement of the procedures used to define research variables

how can you measure the research variable

• ex: can say researchers can ask participants to rate how they feel from a scale from 1-10 on a survey

Hypothesis

A testable prediction, often implied by a theory

independent variable

The experimental factor that is manipulated; the variable whose effect is being studied.

what was done in an attempt to get a result (dependent variable). It can be done by either by the participants or researchers

dependent variable

The outcome factor; the variable that may change in response to manipulations of the independent variable.

the result

random sample

a sample that fairly represents a population because each member has an equal chance of inclusion

sampling bias

a flawed sampling process that produces an unrepresentative sample
occurs when some members of a population are systematically more likely to be selected in a sample than others

Random assignment

assigning participants to experimental and control groups by chance, thus minimizing preexisting differences between those assigned to the different groups

correlation coefficient

a statistical index of the relationship between two things (from -1 to +1)

standard deviation

a computed measure of how much scores vary around the mean score

internal validity

extent to which we can draw cause-and-effect inferences from a study

control group

In an experiment, the group that is not exposed to the treatment; contrasts with the experimental group and serves as a comparison for evaluating the effect of the treatment.

observational study

observes individuals and measures variables of interest but does not attempt to influence the responses