Gah I just wrote a really long post about stats, then sitepoint went down temporarily!
I don’t know what you’re trying to achieve here but you need to be careful with any conclusions you make. Firstly, the sample size is so small you can’t really claim anything is statistically significat. Secondly, as with any survey, you can’t judge how people rate “time wasting” what one person mentions as highly important, someone else may consider insignificant. Finally, you have the “me too” problem. Because it’s an open survey people will read the answers and naturally get reminded of an issue, this will often take over what the would have said otherwise–skewing the results.
So far, we could extrapolate that “Repetition wastes twice as much time as Evaluating 3rd party code” but this isn’t an accurate statement. each occurance of “Evaluating 3rd party code” may take three times as long as each occourance of “repetition”. A more accurate conclusion is that “Repetition is more likely to be a waste of time”… but it may also be easier to work around.
Because your questions are open-ended there’s no way you can know whether some of these are actually related. E.g. Flakey API and Evaluating 3rd party code probably are.
Again, I don’t know what you’re doing with this data but you do need to be wary of any conclusions you make from it.