On Oct 14, 2011, at 09:39 , shl2a wrote: > Dear forum users, > > It's 3:35am and I am swamped with statistics homework lol > I'm terrible with R and this time I have no idea what the prof wants. Here > is the question: > > Consider the (two-‐sample) Wilcoxon rank statistic T = Σrank(Xi). For > n1=106 and n2=192, determine by simulation the α=.05 critical point for > testing H0: θ=0, H1:θ<0. > We can do this as follows: > > For m=10000 (no wimpy m=200 or 500 as in the book), > draw m=10000 subsets of size 106 from the integers 1:298 > using repeatedly the command > > xdat = sample(1:298, size=106). > > For each such subset, the value of the Wilcoxon is sum(xdat). Be sure to > answer the following question: why is it unnecessary to calculate ranks? > > Any help would be greatly appreciately at this time.
Well, he wants you to use your brain, not ours... This is not a list for helping people with their homework. Look through your teaching materials and notes and see if your friendly prof hasn't already provided an example of doing replicated simulations, drawing a histogram of the results, etc. -- Peter Dalgaard, Professor Center for Statistics, Copenhagen Business School Solbjerg Plads 3, 2000 Frederiksberg, Denmark Phone: (+45)38153501 Email: pd....@cbs.dk Priv: pda...@gmail.com ______________________________________________ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.
