Answer the following statement(s) true (T) or false (F)

1. In experimental research, the researcher controls the causal mechanism.
2. Field experiments allow greater control over conditions than do laboratory experiments.
3. Before-and-after designs have no control or comparison groups.
4. A fixed sample panel design is the same thing as a before-and-after quasi-experimental design.
5. A time series before-and-after quasi-experimental design makes multiple observations in both pretest and posttest periods.

1. False
2. False
3. True
4. False
5. True