# Valid to use bar graph for nominal data with "check all that apply"?

I asked survey participants which people influenced their idea of what college will be like, instructing them to "check all that apply." I am trying to see if there is a difference in the type of influences between two populations, so calculating the mean does not make sense. Any advice on what kind of test I can do? Or can I just represent the responses in bar graphs, showing the differences between the two populations?

• Welcome to our site! You seem to be conflating two questions here - whether the bar chart is a suitable representation of your data, and what statistical test you can perform to detect a difference between your populations. I suggest you edit this question (perhaps to focus on the bar chart issue) and ask a second question to focus on the statistical test. Commented Sep 13, 2016 at 13:39
• @silver It seems like one unified question to me in that it asks for a suitable way to compare this kind of "all that apply" response between two groups.
– whuber
Commented Sep 13, 2016 at 15:20
• A bar graph is not a test! If, however, you have decided that the bar graph is the appropriate way to visualize these data, and you are interested in the hypothesis of whether or not any category differs in proportion between the two populations, a $\chi^2$ test of heterogeneity is an appropriate choice. Commented Sep 13, 2016 at 16:08
• @whuber That's fair enough and I see where you're coming from. I do think that the graphical question and the statistical testing issues are somewhat distinct - to the extent that someone may feel qualified to give an answer to one of the two issues, but not the others. In that case splitting the issues into separate questions may allow each to be answered and explored more comprehensively. (I can see there is an underlying unity here, but it doesn't hurt to ask a pair of questions and put a link in each to the other.) Commented Sep 13, 2016 at 17:01