Question

Please respond to the following questions either by writing the design name or by describing the design using standard notation (X= program, O=Observation, R=random assignment. For each design, please discuss all threats to internal validity.
1. Design: Single group post-test only
B. Internal Validity Threats.

2. Design (R) 01 X 02
(R) 01 02
B. Internal Validity Threats

3. Design: Pretest-posttest design with experimental and comparison group

B. Internal Validity Threats

4. Design: O X O

B. Internal Validity Threats

5. Design: Single group with three pretests and four posttests.

B. Internal validity Threats