> On 08 Sep 2016, at 15:48, Michael Dewey <li...@dewey.myzen.co.uk> wrote: > > Dear Matti > > On 08/09/2016 13:06, Matti Viljamaa wrote: >> I’m trying to do a t-test, where the null hypothesis for the two data sets >> has to be: >> >> “the means are the same”/“difference in means is equal to one” >> > > That is two statements not one. Do you mean that your null is that the > difference is 1? If so just subtract 1 from all the scores in the group which > is predicted to be higher and run the t-test on the resulting scores.
Sorry typo, should of course be: “the means are the same”/“difference in means is equal to zero” so they are synonymous. >> Using the t.test function in R I’m able to see that it uses the following >> “alternative hypothesis”: >> >> alternative hypothesis: true difference in means is not equal to 0 > > It means that the null is that the difference is zero. > >> >> but does not seem to specify null hypothesis. I believe alternative and null >> hypotheses are different, although >> I don’t exactly know how. >> >> So what should I use for my t-test? Or is t.test ok? >> >> ______________________________________________ >> R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see >> 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. >> > > -- > Michael > http://www.dewey.myzen.co.uk/home.html ______________________________________________ R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see 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.
