Question

Consider checking the effectiveness of a weight loss program. One approach is to take two random samples, one from those who did not participate in the program, and another from those who participated, and compare the difference. Another is to take a random sample from people who plan to participate, and compare their weights before and after participation. Which of these would be more helpful? Why?

Answer 1

My opinion is that the second option will be more effective. That is to take a random sample from people who plan to participate , and compare their weights before and after participation. Then only we can have a clear cut image about the results of the weight loss program. We can only get a result from a person who is participated in the program. So when we are comparing the results, then we should take a sample from the person before he participated in the program and we should compare that sample with the sample after the program. So in such cases only we can get a more effective and helpful information.

The first option tells about taking random samples from people who did not participate in the program and from people who participated in the program. In that way we cannot get a more useful and helpful information. That comparison doesn't make any sense since one of them are not participated in the program.

We can easily compare the results when we participate in the weight loss program. We will take a sample before participating the weight loss program and we will take another sample after completing the program. And now we should compare the results of the two samples, now we can get clear information about the program's effectiveness.