search for: kurtosis

Dear R users, I hope to explain the concepts of skewness and kurtosis by generating series of distributions with same skewness and different kurtosis or with same kurtosis and different skewness, but it seems that i cannot find the right functions. I have searched the mailing list, but no answers were found. Is it possible to do that in R? Which function could b...

Hello I do not know very much about statistics (and English language too :-( ), then I come in search of a clarification (explanation): I found two distinct results on KURTOSIS and I do not know which of them is the correct one. Any aid will be welcome! klebyn ################ CODE rnorm(1000) -> x library(moments) kurtosis(x) skewness(x) detach("package:moments") library(fBasics) kurtosis(x) skewness(x) detach("package:fBasics") R.vers...

Hi, I'm a newcomer to R, having previously used SPSS. One problem I have run into is computing kurtosis. A test dataset is here: http://www.whinlatter.ukfsn.org/2401.dat > library(moments) > data <- read.table("2401.dat", header=T) > attach(data) > loglen <- log10(Length) With SPSS, I get Skewness -0.320 Kurtosis -1.138 With R: > skewness(loglen) [1] -0.317923...

...d to csv str(dat1) #'data.frame':??? 12573 obs. of? 17 variables: # $ Removed.AGC????????????????????????????? : num? 65.67 46.17 41.26 14.09 5.38 ... # $ Removed.SST????????????????????????????? : chr? "" "46.1658" "41.2566" "14.0931" ... # $ Removed.Kurtosis???????????????????????? : num? NA NA NA NA 5.38 ... # $ Removed.Skewness???????????????????????? : num? 65.67 46.17 41.26 14.09 5.38 ... # $ Removed.QC17999????????????????????????? : num? 65.67 46.17 41.26 14.09 5.38 ... # $ Removed.QC16200????????????????????????? : num? 65.67 46.17 41.26 14.09 5...

I wonder whether the functions for skewness and kurtosis in the e1071 package are based on correct formulas. The functions in the package e1071 are: # -------------------------------------------- skewness <- function (x, na.rm = FALSE) { if (na.rm) x <- x[!is.na(x)] sum((x - mean(x))^3)/(length(x) * sd(x)^3) } # --------------...

Dear friends, I try to get started with R and can’t estimate kurtosis of a random sample by using one command. I have installed R 1.6.2. Please help. Max --------------------------------- ur needs [[alternate HTML version deleted]]

Hi, in which R-package I could find skewness and kurtosis measures for a distribution? I built some functions: gamma1<-function(x) { m=mean(x) n=length(x) s=sqrt(var(x)) m3=sum((x-m)^3)/n g1=m3/(s^3) return(g1) } skewness<-function(x) { m=mean(x) me=median(x) s=sqrt(var(x)) sk=(m-me)/s return(sk) } bowley<-function(x) { q<-as.vector(quanti...

Hi, I cannot find the function kurtosis. Is it sth additional I am meant to download? I use the MacOS X version of R. Many thanks Samira

...Mean 9963040 Largest Std. Dev. 9006352 75% 1.99e+07 2.00e+07 90% 2.00e+07 2.00e+07 Variance 8.11e+13 95% 2.00e+07 2.00e+07 Skewness .18931 99% 2.00e+07 2.00e+07 Kurtosis 1.045409 GSS YEAR FOR THIS RESPONDENT ------------------------------------------------------------- Percentiles Smallest 1% 1972 1972 5% 1973 1972 10% 1974 1972 Obs 40933 25% 19...

Hi, I have the following function: > kurtosis <-function(x) (mean((x-mean(x))^4))/(sd(x)^4) #x is a vector and data > print(mydata) V1 V2 V3 V4 V5 1 1007_s_at DDR1 2865.1 2901.3 1978.3 2 1053_at RFC2 10...

I have a question about the D'Agostino skewness test and the Anscombe-Glynn kurtosis test. agostino.test(x, alternative = c("two.sided", "less", "greater")) anscombe.test(x, alternative = c("two.sided", "less", "greater")) The option "alternative" in those two functions seems to be the null hypothesis. In the...

Dear R-users, I am comparing differences in variance, skew, and kurtosis between two groups. For variance the comparison is easy: just var.test(group1, group2) I am using agostino.test() for skew, and anscombe.test() for kurtosis. However, I can't find an equivalent of the F.test or Mood.test for comparing kurtosis or skewness between two samples. Would the te...

Hello everybody, this is a bit off topic, so maybe you can just reply to me personally... What is the typical notation for 'skewness', 'kurtosis' and maybe 'excess kurtosis'? Thank you, Martina -------------------------------------------------------------------------- Department of Statistics Office Phone: (614) 292-1567 1958 Neil Avenue, 304E Cockins Hall FAX: (614) 292-2096 The Ohio State University E...

I checked the help and the mailing list archives, but I can find no mention of a routine that calculates higher moments like skewness and kurtosis. Of course, these are easy enough to write myself, but I was thinking that they MUST be in here. Am I wrong? Thanks. -Frank

Dear useRs, I was searching CRAN for implementation of kurtosis and skewness tests, and found that there is some kind of lack on it. So, I have written three functions: 1. Anscombe-Glynn test for kurtosis 2. Bonett-Seier test based on Geary's kurtosis (which is not widely known, but I was inspired by original paper describing it, found coincidentally i...

Is there some reasonable way to generate random data from a distribution that has some degree of skewness and/or kurtosis, but would otherwise be normal? thanks, -------------- next part -------------- A non-text attachment was scrubbed... Name: greiff.vcf Type: text/x-vcard Size: 398 bytes Desc: Card for Warren R. Greiff Url : https://stat.ethz.ch/pipermail/r-help/attachments/20011210/2170bc6f/greiff.vcf

Dear all, Right now, I'm doing research about outlier in statistical data (univariate and multivariate) and I want to simulate its behavior. My problem is : How to generate random data from distribution with zero skewness and some kurtosis values in R ? A. Kudus ===================== Dept. of Statistics Bandung Islamic University I n d o n e s i a ========================== -.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.- r-help mailing list -- Read http://www.ci.tuwien.ac.at/~hornik/R/R-FAQ.html Sen...

..., but he has a Maple routine to do just that. 3. from Uwe Ligges <ligges at statistik.uni-dortmund.de> That's a theoretical problem, not an R problem. Or I misunderstood.... At first select a distribution, which a) has zero skewness b) a well defined and preferably easy to calculate kurtosis. After that, choose the parameters of the distribution, so that the theoretical value of the kurtosis is equal to the value you want to get. At last generate renadom numbers for that distribution with the now given parameters. 4. from John Fox <jfox at mcmaster.ca> Why not sample from...

..., but he has a Maple routine to do just that. 3. from Uwe Ligges <ligges at statistik.uni-dortmund.de> That's a theoretical problem, not an R problem. Or I misunderstood.... At first select a distribution, which a) has zero skewness b) a well defined and preferably easy to calculate kurtosis. After that, choose the parameters of the distribution, so that the theoretical value of the kurtosis is equal to the value you want to get. At last generate renadom numbers for that distribution with the now given parameters. 4. from John Fox <jfox at mcmaster.ca> Why not sample from...

Hello everybody, I'm studying descriptive statistics with R and I want to know how to calculate the asymmetry and kurtosis coefficients of a sample using R. I'll appreciate some help. Thanx, Talita Perciano Costa Leite Graduanda em Ci?ncia da Computa??o Universidade Federal de Alagoas - UFAL Departamento de Tecnologia da Informa??o - TCI Constru??o de Conhecimento por Agrupamento de Dados - CoCADa