I have to perform correlation test between repeated and not repeated measures, more accurately e.g.: I sampled 20 individuals in 10 populations and I measured some traits (e.g. height) on the individuals and I have climatic variables (e.g. temperature) for each population. Now I want to compute correlation e.g. between height (10*20 values) and temperature (10*1 value).
Here is my question : is it better to take the mean values of measured traits for each population or to "repeat" the climatic variable for each individual ? (and why ?)
Does anyone know a better way to deal with this issue ?
I hope this is understandable and thank in advance for your help.