----- Original Message ----- From: "Romain Francois" <[EMAIL PROTECTED]> To: "Pieter Provoost" <[EMAIL PROTECTED]>; "RHELP" <[email protected]> Sent: Thursday, April 28, 2005 2:03 PM Subject: Re: [R] normality test
> Le 28.04.2005 13:16, Pieter Provoost a �crit : > > >Hi, > > > >I have a small set of data on which I have tried some normality tests. When I make a histogram of the data the distribution doesn't seem to be normal at all (rather lognormal), but still no matter what test I use (Shapiro, Anderson-Darling,...) it returns a very small p value (which as far as I know means that the distribution is normal). > > > >Am I doing something wrong here? > >Thanks > >Pieter > > > > > Hello, > > You seem to know not far enougth. > Null hypothesis in shapiro.test is **normality**, if your p-value is > very small, then the data is **not** normal. > > Look carefully at ?shapiro.test and try again. Furthermore, normality > tests are not very powerful. Consider using a ?qqnorm and ?qqline > > Romain Thanks, I thought null hypothesis for these tests was "no normality"... Pieter ______________________________________________ [email protected] mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide! http://www.R-project.org/posting-guide.html
