On May 2, 2012, at 15:48 , meredith wrote: > Peter- > Maybe I have not articulately my problem clearly, I have had local help > with the statistical part just trying to figure out how to correctly program > this test. For clarity's sake, I have months worth of data, I want to > potentially combine those months into four, shall we say seasons, that have > close to the same behaviour. Therefore to do this, I am trying a monthly > moving window to categorize these seasons. After talking to a couple water > resources statisician's we decided the way to test if the months are > different is through the use of hypothesis testing and a dummy variable. So > I have one regression, Model A, that includes a zero in the dummy spot with > the two months of data combined, then I have another regression, Model B, > that includes the interaction term for the changes between the months (the > intercept changes, using a 0 or 1 dummy variable). Now we discussed running > a Wald testing, Chi squared, to test to see if the interaction term is of > importance probability wise, can I do this utilizing anova? Does this make > more sense? Then I will run another set of restricted and unrestricted > models to account for potential differences in the mean (i.e the slope). > Does this explain my problem better?
Not really. It does indicate that Bert is right, though: You need to enlist a local statistician. There are things clearly not understood, which we cannot help you with on this list. -pd PS. This is a mailing list. Please quote context. > > Meredith > > -- > View this message in context: > http://r.789695.n4.nabble.com/Hypothesis-Testing-using-Wald-Criterion-for-two-regression-models-with-dummy-variables-tp4601582p4603260.html > Sent from the R help mailing list archive at Nabble.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. -- 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.