ex post facto design

research that examines past occurrences in order to understand a current state. Although this type of design involves both a dependent variable and an independent variable, the investigator cannot manipulate the latter. For example, a researcher who is interested in determining the effectiveness of a particular television advertisement on consumer behavior may recruit a group of participants who saw the advertisement and a group of participants who did not, yet the researcher has no control over which specific people actually viewed the advertisement. Also called ex post facto study. [from Latin ex post facto, “after the event”]

Browse dictionary by letter

a b c d e f g h i j k l m n o p q r s t u v w x y z

Psychology term of the day

May 9th 2024

slow-wave sleep

deep sleep that is characterized by increasing percentages of particular types of delta waves on the electroencephalogram, corresponding to Stages 3 and 4 of NREM sleep. See also sleep stages.