Dear R Developers: I have been playing with R, release 2.0.1 for a week now and have detected = that all stat functions related to distribution probabilities have the same= problem:
1.- According to the manual the log.p parameter is always the last one. 2.- When you use the software, the last parameter seems to be lower.tail Example: > pt (1.1, 5) [1] 0.8392746 > pt (1.1, 5, F) [1] 0.8392746 > pt (1.1, 5, F, T) [1] 0.8392746 >=0D On this example, I have used the Student T distribution. The result of this= example has been tested with the stat calculator at http://calculators.sta= t.ucla.edu/. 1.- This first line shows that when this function has two arguments, the lo= g.p default value is false, and the lower.tail is true. 2.- The second line shows that when this function has 3 arguments, the last= one is the log.p argument and the lower.tail is taken by default to true. 3.- The third line shows that when this function has 4 arguments, the third= one keeps on being the log.p argument and the lower.tail is the last one. 4.- Acording to the mannual, the lower.tail should be the third argument an= d not the last one. Best regards, =0D Jos=E9 Luis Casado Mart=EDnez ------------------------------------------------------------------ European Computing Consultants C/ Hermanos Garc=EDa Noblejas, N=BA 39, 5=AA, N 1 28037 Madrid Telf.: 34-91-406 19 15. Fax: 34-91-406 19 16 Movil: 34-607-750 316 ------------------------------------------------------------------ The last line shows that the sum of probabilities of 1.1 using 5 degrees of= freedom adding the lower tail (pt (1.1, 5, F, T)) and not adding the lower= tail ( pt (1.1, 5, F, F)) is 1. This is not the case with log (p). _____________________________________________________________________ Mensaje analizado y protegido, tecnologia antivirus www.trendmicro.es [[alternative HTML version deleted]] ______________________________________________ [EMAIL PROTECTED] mailing list https://stat.ethz.ch/mailman/listinfo/r-devel
