Question

Define the following terms: 1. Confound 2. Internal Validity 3. Multiple-group Time-series Design 4. Non-equivalent Control Group Posttest Only Design 5. Non-manipulated Independent Variable 6. Regression to the Mean 7. Single-group Posttest Only Design 8. Single-group Pretest-posttest Design 9. Single-group Time-series Design 10. Systematic Replication 11. Testing Effect

Answer 1

1. Confound: a confounder is a variable which affects both dependent and independent variable causing a wrong association.

2. Interval validity: internal validity refers to how well an experiment is done when it avoids confounding. The less the chance of confounding the higher the interval validity.

3. Multiple group time series design: a tour of quasi- experimental design ( subject to concern regarding interval validity), where a series of periodic experiments are taken from two groups of test units.

4. Non-equivalent control group posttest only design: in this design, participants in one group are exposed to a treatment while a non-equivalent group is not exposed and then the two groups are committe in various factors, ensuring that the experiment has high level of internal validity.