I want to compare how does a dependent variable (total flow) changes with a covariate (total rain) between two groups (stream A & B). Usually, i would go with ANCOVA. But these groups have the same number of observations. And each observation in A correspond to an observation in B, because they were generated from the same rain event (total rain). Do i:
- Do an ANCOVA/multiple-regression
- Find the difference between A and B, then regress those values against the covariate?
If method 2 is better, i have tried and got some negative values from A-B. How do i go about it?
I hosted the sample data here