PSYC 201W Lecture Notes - Lecture 6: Dependent And Independent Variables, Intelligence Quotient, External Validity
Document Summary
Chaper 6: random selection rarely used - researchers focus on iv, purposive and convenience samples typically used, external validity increased by replication. Iq may be potential confound, so give iq test to participants (could random assign to simplify process: matching, equate participants on specific variables (should be done with variables related to iv or may confound dv) Advantages: controls for variables on which participants are matched. Each control participant is yoked to an experiment (takes self-chosen snack break: matching by equating participants (individual matching, match case by case then randomly assign to groups. Advantages: groups equated on potential extraneous variables. Disadvantages: identifying variables to match is difficult, decreases generalization: counterbalancing, used only with repeated measure (within participants) design, all participant retrieve all treatment conditions. Types of sequencing effects: order effects - arising from order treatment conditions are administered, carryover effects - when performance in treatment condition effect performance in another treatment condition.