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Hello list, I am dealing with a noisy function (gradient,hessian not available) with simple boundary constraints (x_i>0). I've tried constrOptim() using nelder mead to minimize it but it is way too slow and the returned results are not satisfying. simulated annealing is so hard to tune and it always crashes R program in my case. I wonder if there are any packages or functions can do

Hello list, Is there any function in some package can calculate two sample Cramer-von Mises test statistic? I searched around and only find one sample version cvm.test() in nortest package. thanks, WC _________________________________________________________________ Don’t just search. Find. Check out the new MSN Search!

Hi list, I tried to use nls to do some nonlinear least square fitting on my data with 340 observations and 10 variables, but as I called nls() function, I got this error message: Error in qr.qty(QR, resid) : 'qr' and 'y' must have the same number of rows Then I traced back a little bit into nls() function, the error seemed to happen when calling nlsiter() internal function, but

Hi list, I am building a regression model with categorical predictor variable coded by treatment contrasts. The summary of the regression model shows that some levels are significant while others are not. The significant ones show that they are statistically significant from the basis factor (at level 0). How do we generally deal with those insignificant levels? If they are used for

Hi there, I am trying to write a c++ shared library for R. I need a function which has the same functionality as sample() in R, i.e., does permutation, sample with/without replacement. Does R have internal sample routine so that I can call it directly? I did not find it in R.h, Rinternal.h. Thanks