Question

Could you randomly select 100 from your list of 1000 and then nonrandomly (haphazardly) assign them to treatment or control.

Answer 1

Random selection of sample refers to randomly selecting individuals from a group called population. Random assignment refers to randomly assigning the sample to either of the two groups. Yes, it is possible to randomly select 100 from your list of 1000 and then non-randomly (haphazardly) assign them to treatment or control. Randomization of sample from a population increases the possibility of getting the representative sample. Randomly assigning the sample to the two groups increases the validity of the test. However, though the non-random assignment of sample to groups is possible, the validity of the test would be questionable then.