AP Stats CH. 4.3 - Designing Studies

individuals randomly assigned to groups + randomly selected

• inference about population can be made

• inference about cause & effect can be made

individuals randomly assigned to groups + not randomly selected

• no inference about population

• inference about cause & effect

individuals not randomly assigned to groups + randomly selected

• inference about population

• no inference about cause & effect

individuals not randomly assigned to groups + not randomly selected

• no inference about population

• no inference about cause & effect

criteria for establishing causation

• association is strong

• association is consistent

• Larger values of explanatory variable are associated w/stronger responses

• alleged cause precedes effect in time

• alleged cause is plausible

Basic Data Ethics: Institutional Review Board

All planned studies must be reviewed in advance by an institutional review board charged with protecting the safety & well-being of the subjects.

Basic Data Ethics: Informed Consent

All individuals who are subjects in a study must give their informed consent before data are collected.

Basic Data Ethics: Confidentiality

All individual data must be kept confidential. Only statistical summaries for groups of subjects may be made public.