Chapter 8

1. Chapter 8 Experience carefully exploited: Quasi-experimental research designs

2. Why Quasi-Experiments? • Maximize internal and external validity • When random assignment can’t be done • When random assignment shouldn’t be done

3. Kinds of Quasi-Experiments • Person-by-treatment quasi-experiments • Natural experiments • Nature and treatment designs • Natural groups with experimental treatment • Nature-by-treatment studies

4. Comparability and Patching • Comparable and non-overlapping groups • Patched-up designs: • One group, pretest-posttest design • Posttest-only with nonequivalent groups • Pretest-posttest with nonequivalent groups • Time-series designs • Internal analyses

5. When True Experiments and Quasi-Experiments Collide • Consistencies and inconsistencies in the results of true experiments compared to quasi-experiments

6. Person-by-treatment quasi-experiment Prescreening Extreme groups Median split Natural experiments Natural groups with experimentaltreatment Comparable and non-overlapping groups Patched-up design Patching One-group design One-group pretest-posttest design Posttest-only design with non-equivalent groups Key Terms from Chapter 8

7. Pretest-posttest with non-equivalent groups Time-series design Internal analysis Name-letter effect Key Terms from Chapter 8