#################################################################################R Code to Supplement#Design of Experiments with MINITAB#byPaul Mathews#published by ASQ Quality Press (2004)#################################################################################Thisfile contains R code that reproduces the examples from Design of Experiments#with MINITAB by Mathews.In some cases, alternative and extra methods are given where#R has special capabilities.#Thecode contained here was run on R Version 2.0.1 and produces output comparable to#that from MINITAB V14.There are probably more accurate, efficient, or better ways of#producing the same or similar output in R than the methods shown here, but the methods#shown work.#Ifyou find any mistakes or have recommendations on how to improve this document#pleasecommunicatethem to me by e-mail at the address below.#Paul Mathews and MM&B Inc. take no responsibility for the accuracy, stability, use,#or misuse of any of the R code contained here.#Copyright2005 Paul Mathews#Paul Mathews, President#Mathews Malnar and Bailey, Inc.#217 Third Street,Fairport Harbor,OH44077#Phone: 440-350-0911#Fax: 440-350-7210#E-mail:paul@mmbstatistical.com#Web: www.mmbstatistical.com#Rev.4/20/05(PGM)

###################################################################################R Conventions###################################################################################Command prompt: R commands are submitted by typing them at the command prompt ">".#Two or more commands separated by semicolons may appear on the same line. If an R#command is too long for one line, hit and R will allow you to continue the#command on the next line at the "+" prompt. For example:#> help(#+ lm)#Find help for the lm function.#Several commands that need to be considered together may be collected within braces#{} which may be separated over several lines.#Objects: Data in R and the output of R analyses are all "objects" that have properties#defined within R. For example, the R command:#> Y.lm = lm(Y~X)#fits a linear model for Y as a function of X. The output of the lm function is assigned#to the new object Y.lm, but the lm function by itself doesn't create any visible output.#There are other functions which extract information/output from Y.lm: summary(), anova(),#coefficients(), residuals(), plot(), etc. The results from each of these functions are#themselves objects.#Object names: R commands and object names are case sensitive. For example, the command#"anova" is different from "Anova". Object names must start with a letter and can contain#numbers and limited special characters. Periods are commonly used as delimitors in object#names, e.g. y.lm.residuals.#Object class: Objects have different classes that have different properties. When objects#are passed to a function, they must be compatible with the expected class required by the#function. Many errors in R commands are caused by mismatched object classes.#Assignment operations: Objects are assigned values using the R assignment operators "="#or "