PSY 250 Lecture Notes - Lecture 10: Flextime, Random Assignment, External Validity
Document Summary
Increases basic knowledge and evaluates theory: research ex - context-dependent memory. Evaluates theory: supported importance of context effects in memory. Potential coercion when in industrial or corporate settings. External validity increases due to naturalistic settings and real-world problems. Internal validity can suffer due to a lack of control. Difficult to create equivalent groups - difficult to use random assignment. Purpose to evaluate the effectiveness of the treatment. Treated experiment group & not treated control group. Random assignment is not possible for practical reasons. The groups experience different events in the study itself. 1 level of iv for one group, second level of iv for other nonequivalent group. Typically includes pretests (o1) & posttests (o2) observations before and after treatment (t) Experiment group: pittsburgh plant tries new flextime schedule. Control group: cleveland plant maintains traditional work schedule. Remember from ch 6: matching is typically used for between-subjects" experimental designs with a manipulated iv.
