Let’s say you send out a survey to 100 random people with a single yes/no question. 80 people response and 60 of those 80 people say yes and the other 20 say no. The classic question in statistics is: what percent of the population would say yes to this question if they all responded? The first approach would be to say 60 of the 80 responded said yes so we would estimate that the population “yes rate” would be 75%.