Re: [R] Query about wilcox.test() P-value

2010-07-15 Thread Govind Chandra
Thanks to Peter Konings, Peter Ehlers, Marc Schwartz and Peter Dalgaard my query has been satifactorily addressed. Govind __ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-pr

Re: [R] Query about wilcox.test() P-value

2010-07-14 Thread Peter Dalgaard
Marc Schwartz wrote: > You need to understand the difference between how a value is stored > in an R object with full floating point precision versus how a value > in R is displayed (printed) in the console with a print "method". > > In this case, wilcox.test() returns an object of class 'htest' (

Re: [R] Query about wilcox.test() P-value

2010-07-14 Thread Marc Schwartz
You need to understand the difference between how a value is stored in an R object with full floating point precision versus how a value in R is displayed (printed) in the console with a print "method". In this case, wilcox.test() returns an object of class 'htest' (as noted in the Value sectio

Re: [R] Query about wilcox.test() P-value

2010-07-14 Thread Govind Chandra
Hi Peter, Thanks for your response. Yes, I am interested in P-values smaller than 1e-16. Below a certain value they may not tell much about significance but are useful for ordering (ranking), for example, differentially expressed genes in microarray data. Something similar is done by sequence sim

Re: [R] Query about wilcox.test() P-value

2010-07-14 Thread Peter Ehlers
On 2010-07-14 3:53, Govind Chandra wrote: Hi, I find that the p-value printed out by wilcox.test() and the p-value stored in the p.value attribute in the object returned by wilcox.test() are not the same. There seems to be a lower limit of 2.2e-16 for the printed value although it does say that

[R] Query about wilcox.test() P-value

2010-07-14 Thread Govind Chandra
Hi, I find that the p-value printed out by wilcox.test() and the p-value stored in the p.value attribute in the object returned by wilcox.test() are not the same. There seems to be a lower limit of 2.2e-16 for the printed value although it does say that it is less than that. What I want to know is