Hi everyone, I am writing this to get your help. I have a big data set and I
wanted to do multiple regression and repeat this process several timesfor
example (data)where y: dependent variables ; number of columns are 5, nrow =
1800y temp, preci, growing season days, max temp, min temp region4 23 0
127 35 14 NORTH AMER10 35 21
120 32 17 NORTH AMER1 18 1
90 27 12 EUROPE...........
1) here I wanted to do linear regression (simple regression) using each
predictor (temp, preci, growing season days, max temp... etc), separatelyafter
that, I want to second quadratic regression using each predictor, and third -
polynomial (cubic)2) I wanted to compare the models (linear, quadratic and
cubic) and chose the best model 3) I wanted to do multiple regression using the
best model of each variable Further, I wanted to divide the data into groups by
region. and, then perform the above analysis for each group (by region)and, I
wanted to compare the residuals between the models where I have been using all
data set and the models by region
I was trying to do manually, but it is taking so much time. I think it is not
difficult and does not take time to write script in R. I was trying to make
loop but I could not succeedI would be very grateful if you help me how I can
write script (loop function) and compute the analysis in R. Thanks for your
support.
Sincerely,
Kristi GloverUniversity of Windsor, Windsor, Canada
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