Re: [R] Normality tests on groups of rows in a data frame, grouped based on content in other columns

2011-10-31 Thread Joel Fürstenberg-Hägg
Hi Dennis, Thanks for your prompt response. Best, Joel >>> Dennis Murphy 30-10-2011 21:11 >>> Hi: Here are a few ways (untested, so caveat emptor): # plyr package library('plyr') ddply(df, .(Plant, Tissue, Gene), summarise, ntest = shapiro.test(ExpressionLevel)) # data.table package libr

Re: [R] Normality tests on groups of rows in a data frame, grouped based on content in other columns

2011-10-30 Thread Dennis Murphy
Hi: Here are a few ways (untested, so caveat emptor): # plyr package library('plyr') ddply(df, .(Plant, Tissue, Gene), summarise, ntest = shapiro.test(ExpressionLevel)) # data.table package library('data.table') dt <- data.table(df, key = 'Plant, Tissue, Gene') dt[, list(ntest = shapiro.test(Exp

[R] Normality tests on groups of rows in a data frame, grouped based on content in other columns

2011-10-30 Thread Joel Fürstenberg-Hägg
Dear R users, I have a data frame in the form below, on which I would like to make normality tests on the values in the ExpressionLevel column. > head(df) ID Plant Tissue Gene ExpressionLevel 1 1 p1 t1 g1 366.53 2 2 p1 t1 g2 0.57 3 3 p1 t1 g311.81 4 4

Re: [R] Normality tests

2011-04-26 Thread Jorge Ivan Velez
Hi Bruce, One way is via apply() # some data set.seed(123) X <- matrix(rnorm(100), ncol = 5) X # tests t(apply(X, 2, function(x){ sw <- shapiro.test(x) c(sw$statistic, P = sw$p.value) })) See ?apply and ?str and ?shapiro.test for more information. HTH, Jorge

Re: [R] Normality tests

2011-04-26 Thread Jerome Asselin
On Tue, 2011-04-26 at 16:15 -0400, Bruce Kindseth wrote: > I have a large amount of data which I break down into a collection of > vectors of 100-125 values each. I would like to test the normality of the > vectors and compare them. In the interactive mode I can test any one vector > using the Sh

Re: [R] Normality tests

2011-04-26 Thread Peter Ehlers
On 2011-04-26 13:15, Bruce Kindseth wrote: I have a large amount of data which I break down into a collection of vectors of 100-125 values each. I would like to test the normality of the vectors and compare them. In the interactive mode I can test any one vector using the Shapiro-Wilk test or t

[R] Normality tests

2011-04-26 Thread Bruce Kindseth
I have a large amount of data which I break down into a collection of vectors of 100-125 values each. I would like to test the normality of the vectors and compare them. In the interactive mode I can test any one vector using the Shapiro-Wilk test or the Kolmogorov-Smirnov test. My problem is th

Re: [R] normality tests

2010-08-12 Thread Bert Gunter
?RsiteSearch or consult package sos. Learn how to use R's search resources! -- Bert Gunter Genentech Nonclinical Statistics On Wed, Aug 11, 2010 at 8:21 PM, Geoffrey Smith wrote: > Hello, does anyone know how to compute the following two normality tests > using R: > > (1) the Kiefer-Salmon (1

[R] normality tests

2010-08-11 Thread Geoffrey Smith
Hello, does anyone know how to compute the following two normality tests using R: (1) the Kiefer-Salmon (1983) statistic, Economics Letters 11, p. 123-127 (2) the modified Shapiro-Wilk statistic? Thank you very much. Geoff [[alternative HTML version deleted]] __