A. Instrumentation effects B. Expectancy C. Testing effects D. Selection bias 3. Which is NOT true of crossover designs? A. They are very efficient. B. They allow multiple treatments to be studied with fewer participants. C. They are useful when treatment effects are stable. D. They allow both treatments to be tested on more subjects, thus allowing for more confidence in the results.
1. B. Expectancy. Not telling participants whether they are in the control or experimental group helps to control for the threat of expectancy. This means that participants are less likely to act differently or have different expectations based on their knowledge of which group they are in. Pre-Experimental Research Design Essay Paper
2. 4. Placebo Selection bias, history, and maturation are all threats to validity that can impacted results of a study. Placebo, on the other hand, is a treatment condition rather than a threat to validity,
3. C. They are useful when treatment effects are stable. Crossover designs are not useful when treatment effects are stable. This is because participants receive both treatments, making it difficult to determine whether any changes in their responses are due to the first or second treatment.
4. 2. They are ideal because they can be generalized to the real world. Experimental designs are not ideal because they can be generalized to the real world. This is because they often involve tight controls that may not be present in real-world settings.
5. Randomized three-group. Randomized crossover, randomized two-group, and randomized two-group pretest-post-test are all examples of experimental research designs. Randomized three-group, however, is not an experimental research design.
6. 4. Static two-group comparison. One-shot, nonequivalent control group, and one group pretest-post-test are all examples of pre-experimental research designs. Static two-group comparison, however, is not a pre-experimental research design. Pre-Experimental Research Design Essay Paper