Its fine on the criticism, part of the paper is writing a section where you list the shortcomings on your survey after having gotten all of the data, and how you would revise it if you were doing it again. The reason that it just lists 7 miles is because the survey was originally just for people who commuted to a specific place, and the question was asking them how far they lived from that place, but then I realized that there might not have been 100 people who rode bikes there, and even if there was interviewing all of them would have been hard, so I changed it slightly, I guess without accounting for the differences.