I have used PMCC for other data in the coursework. The exam board wants us to use spearmans rank in the coursework, but according to my teacher I cannot use it for the measures my hypothesis focuses on, and have to do species frequency against height. It seems I have to guess the correlation between sdi and height. It seems totally wrong to me, but he's telling me to 'correct' it.
The other thing I can't understand is that im trying to prove the assumption that the height of the soil on the hill has an effect on its water content. I don't know any other way to do this other than correlate the two variables, but apparently this too is wrong, as I am comparing two environmental factors????
Thanks for your help