Key Terms

empiricism

scientific method

theory

hypothesis

empirical method

operational definition

instrument

validity

reliability

power

demand characteristics

naturalistic observation

double-blind

frequency distribution

normal distribution

mode

mean

median

range

standard deviation

variable

correlation

correlation coefficient

natural correlation

third-variable correlation

matched samples technique

matched pairs technique

third-variable problem

experiment

manipulation

independent variable

experimental group

control group

dependent variable

self-selection

random assignment

internal validity

external validity

population

sample

case method

random sampling

informed consent

debriefing