1. Quantitative Research  Adequate experimental control  Lack of artificiality  Basis for comparison  Adequate information from the data  Uncontaminated data  No confounding of relevant variables  Representativeness  Parsimony  Pretest-posttest control group design  Posttest only control group design  Solomon four group design  Counterbalanced design  Factorial design Criteria Experimental Designs

2. Criteria #1 Adequate Experimental Control There are adequate restraints, or controls, on the conditions of the experiment. With controls in place the researcher should be able to accurately interpret the results. The experimental design should be structured in such a way that the experimental variable (or treatment) effect can be detected.

3. Criteria #2 Lack of Artificiality The experiment must be conducted in such a way that the results will apply to the real educational world.

4. Criteria #3 Basis for Comparison There must be some way to make a comparison to determine whether or not there is an experimental effect. In some cases a control group is used (control groups do not receive the experimental treatment). In some cases multiple treatments may be studied against an external criterion (i.e. Different reading techniques may be examined to assess their relative impact on student reading scores).

5. Criteria #4 Adequate Information From the Data There must be adequate data for testing the hypothesis. The data must be such that statistical testing will be precise enough for the researcher to make a decision about the hypothesis.

6. Criteria #5 Uncontaminated Data The data should adequately reflect the experimental effects. The data should not be affected by poor measurement or errors in the experimental procedures. Example: subjects in an experiment should not communicate across groups (control and experimental).

7. Criteria #6 No Confounding Variables Confounding of variables occur when two or more variables cannot be separated. Experimental controls should be such that variables can be isolated. Translation: the relationship between independent variable and the dependant variable can be measured with confidence in that another variable is not contributing to the effect.

8. Criteria #7 Parsimony Keep it simple! This criterion means that, with all other factors being equal, a simple design is preferred to a more complex one. Note: simple designs are usually easier to implement, and may yield data that is easier to interpret.

9. Quantitative Experimental Designs This family of research designs is characterized by random selection of subjects. ******* The following experimental designs are based on the problem statement: The effects of teaching method(s) on history achievement.

10. Experimental Design #1 Pretest-Posttest Control Group Design Diagram OOOO OOOO X1XX1X

11. Experimental Design #2 Posttest-Only Control Group Design Diagram OOOO X1XX1X

12. Experimental Design #3 Solomon Four Group Design Diagram OOOO X1XX1X OOOO OOOO X1XX1X

13. Experimental Design #4 Counterbalanced Design Diagram X1XX1X OOOO OOOO XX1XX1

14. Experimental Design #5 Factorial Design Diagram Independent Variable #1 Teaching Method Independent Variable #2 Aptitude Lecture OnlyReading/Lecture/Small Groups Randomly assigned 3 rd graders scoring above 85 on an aptitude test. Randomly assigned 3 rd graders scoring about 85 on an aptitude test. Randomly assigned 3 rd graders scoring below 60 on an aptitude test.