On Thu, 2007-02-15 at 18:44 -0600, Inman, Brant A. M.D. wrote: > R-helpers: > > In the construction of control charts for statistical quality control > objectives, one might choose to estimate the control limits for the mean > using the mean range of the samples. This requires multiplying the mean > range by a correction factor, often called "d2", that is tabulated in > many books. The origin of "d2" seems to be table 2 of the following > paper: > > Harter, HL. Ann Math Stat (1960) 31: 1122. > > In Table 2 of this paper, the mean of the sampling distribution of the > range statistic is calculated for various sample sizes. Does anyone > know whether R has a function that can reproduce the sampling > distribution of the range represented in the Harter paper so that I > don't have to look at tables in old books? > > Brant
Brant, You might want to look at the 'qcc' package on CRAN. Brief info here: http://cran.us.r-project.org/src/contrib/Descriptions/qcc.html Also, take a look at the Qtoolbox at: http://www.cmis.csiro.au/S-PLUS/qtoolbox/R.html HTH, Marc Schwartz ______________________________________________ [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 and provide commented, minimal, self-contained, reproducible code.
