I have recorded the the rate at which water exits a tank on-site and through a video recording and it looks something like this:
|Water Level||Flow Rate (On-site)||Flow Rate (Video)|
I want to know if there is a statistically significant difference in the flow rate measured by the two different methods but I'm not quite sure what is the appropriate test.
I was told to use the kruskal-wallis test, which to my understanding is the wilcoxon rank sum test but for more than two groups. However, in my own opinion, I think the data can be paired so the wilcoxon signed rank test might be more appropriate.
I would like to know which is the correct test to use? Is it the wilcoxon rank sum test, wilcoxon signed rank test or some other test?