Hello. I wonder why sometimes the evaluators use the entire population for data collection? It’s so expensive and also time-consuming. Could anyone give me a clue?

Welcome.

Thanks a lot!

Sometimes I find it very confusing too. As far as I know, one explanation for including the entire population in program evaluation is political, as some people may be offended or upset if they are not included. Hence, it’s more accepted if all people can participate rather than only a random sample.