Unit 3 Experimental Design Concepts

Front

Confounding

Back

Occurs when two variables are associated in such a way that their effects on a response variable cannot be distinguished from each other.

Front

Treatment

Back

A specific condition applied to the individuals in an experiment. If an experiment has several explanatory variables, we use a combination of specific values of these variables.

Front

Experimental Unit

Back

The object to which a treatment is randomly assigned.

Front

Subjects

Back

Experimental units that are human beings.

Front

Placebo

Back

A treatment that has no active ingredient but is otherwise like other treatments.

Front

Factor

Back

An explanatory variable that is manipulated.

Front

Levels

Back

Different values of a factor.

Front

Control Group

Back

Provides a baseline for comparing the effects of other treatments.

Front

Placebo Effect

Back

Describes the fact that some subjects in an experiment will respond favorably to any treatment, even an inactive treatment.

Front

Double-Blind Experiment

Back

Neither the subjects nor those who interact with them and measure the response variable know which treatment a subject is receiving.