1. Lecture 17 Psyc 300A

2. HW 8: Setting Up a Factorial ANOVA Serve Other Serve Other Serve Self Serve Self Alone With Another 5735 5836 5946 6947 6746 6835 6836 5946 5947 5746

3. HW8: SPSS Data File WhoFor WhoWithRating (other vs self)(alone vs with another) 115 116 ……. 127 128 ……. 213 …… 225 226

4. Another SPSS Example Hand raising study –Do boys and girls raise their hands in school at different frequencies? –Do children of different ages raise their hands at different frequencies? –Does how much a boy or girls raises their hand depend on their age?

5. Quasi-Experiments May include the following: –No control group –Non-manipulated IV, participant variable –No random assignment to groups Major problem: Confounding Example: –An intervention to reduce fear of public speaking

6. Types of Quasi-Experiments Single-Group Posttest-Only Design (Tx group) Tx  O Single-Group Pretest/Posttest Design (Tx group) O  Tx  O Single-Group Time Series Design (Tx group) O  O  O  Tx  O  O

7. Types of Quasi-Experiments Nonequivalent Control Group Posttest- Only Design (Tx group) Tx  O (Control group) Tx  O Nonequivalent Control Group Pretest/Posttest Design (Tx group) O  Tx  O (Control group) O  No Tx  O

8. Types of Quasi-Experiments Multiple-Group Time-Series Design (Tx group) O  O  O  Tx  O  O (Cntrl grp) O  O  O  Tx  O  O

9. Threats to Validity Selection: Occurs when one group initially differs from another Maturation: Participants change over time Attrition/Mortality: Occurs when participants drop out History: Events take place between measurements that are not related to IV Instrumentation: Changes may occur in the measurement device over time (including human measuring devices) Testing: Effects of repeated measurement on same person Statistical Regression: Arises when participants are selected based on extreme scores

10. Single-Subject (or Case) Designs Advantages –Simple –In a group design, the mean differences may not represent any particular individual Disadvantages –External validity, generalizing results –Work best on IVs which have reversible effects

11. Reversal Designs ABA reversal design ABAB reversal design –This reversal ends with treatment condition Example: –Caffeine and my clarity in the classroom A=caffeinated coffee, B=decaf –Coaching and my clarity in the classroom A=no coaching, B=coaching

12. Multiple-Baseline Design We look at the effect of introducing a treatment across different –Participants Ex: Using students’ names to increase class participation in PSYC 300A –Behaviors Ex: Using praise to increase cooperation at home (cleaning room, doing dishes, yard work) –Situations Ex: Mom, dad, and caretaker-grandparent use listening skills sequentially with quiet kid