# How to Save the residuals of an LM object greater or less than a certin value to an R object?

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## How to Save the residuals of an LM object greater or less than a certin value to an R object?

 Dear list members, I want to  save residuals above or less than a certain value to an R object. I have performed a multiple linear regression, and now I want to find out which cases have a residual of above + 2.5 and – 2.5. Below I provide the R  commands I have used. Reg<-lm(a~b+c+d+e+f) # perform multiple regression with a as the dependent variable. Residuals<-residuals(reg) # store residuals to an R object. stdresiduals<-rstandard(reg) #save the standardized residuals. #now I want to type a  command that will save the residuals  of certain range to an object. I realize that by plotting  the data I can quickly  see the  residuals outside a certain boundtry, however, I am totally blind, so visually inspecting the plot is not possible for me. Thank you for any help. Regards, Faiz. ______________________________________________ [hidden email] mailing list -- To UNSUBSCRIBE and more, see https://stat.ethz.ch/mailman/listinfo/r-helpPLEASE do read the posting guide http://www.R-project.org/posting-guide.htmland provide commented, minimal, self-contained, reproducible code.
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## Re: How to Save the residuals of an LM object greater or less than a certin value to an R object?

 Residuals are stored as a numeric vector. The R software comes with a document "Introduction to R" that discusses basic math functions and logical operators that can create logical vectors: abs( stdresiduals ) > 2.5 It also discusses indexing using logical vectors: stdresiduals[ abs( stdresiduals ) > 2.5 ] Note that in most cases it is worth going  the extra step of making your example reproducible [1][2][3] because many problems arise from issues in the data or in code that you don't think is broken. [1] http://stackoverflow.com/questions/5963269/how-to-make-a-great-r-reproducible-example[2] http://adv-r.had.co.nz/Reproducibility.html[3] https://cran.r-project.org/web/packages/reprex/index.html (read the vignette) -- Sent from my phone. Please excuse my brevity. On February 22, 2018 8:09:49 PM PST, faiz rasool <[hidden email]> wrote: >Dear list members, > >I want to  save residuals above or less than a certain value to an R >object. I have performed a multiple linear regression, and now I want >to find out which cases have a residual of above + 2.5 and – 2.5. > >Below I provide the R  commands I have used. > >Reg<-lm(a~b+c+d+e+f) # perform multiple regression with a as the >dependent variable. > >Residuals<-residuals(reg) # store residuals to an R object. >stdresiduals<-rstandard(reg) #save the standardized residuals. >#now I want to type a  command that will save the residuals  of >certain range to an object. > >I realize that by plotting  the data I can quickly  see the  residuals >outside a certain boundtry, however, I am totally blind, so visually >inspecting the plot is not possible for me. > >Thank you for any help. > >Regards, >Faiz. > >______________________________________________ >[hidden email] mailing list -- To UNSUBSCRIBE and more, see >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. ______________________________________________ [hidden email] mailing list -- To UNSUBSCRIBE and more, see https://stat.ethz.ch/mailman/listinfo/r-helpPLEASE do read the posting guide http://www.R-project.org/posting-guide.htmland provide commented, minimal, self-contained, reproducible code.
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## Re: How to Save the residuals of an LM object greater or less than a certin value to an R object?

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## Re: How to Save the residuals of an LM object greater or less than a certin value to an R object?

 In reply to this post by Faiz Rasool Hi Peter, the "residuals()" function returns the residuals of a model fitted using the "lm" function. For instances, using the example included in the help of lm: ctl <- c(4.17,5.58,5.18,6.11,4.50,4.61,5.17,4.53,5.33,5.14) trt <- c(4.81,4.17,4.41,3.59,5.87,3.83,6.03,4.89,4.32,4.69) group <- gl(2, 10, 20, labels = c("Ctl","Trt")) weight <- c(ctl, trt) lm.D9 <- lm(weight ~ group) my_res <- residuals(lm.D9) print(my_res) The object returned by "residuals()" is a vector, so you can make any operation with it. For instance: my_res[my_res >= 0.1] About your second question, I don't entirely understand what you want. The "which()" function returns the indexes for which the condition is TRUE. In this case, that the absolute value is greater than 2.5. Alberto Garre > Also, > > which( abs( stdresiduals ) > 2.5 ) > > will tell you which of the standardized residuals are bigger than 2.5 in absolute value. It returns a vector of indices, as in > > > set.seed(1234) > > x <- rnorm(100) > > which (abs(x) > 2.5) > [1] 62 > > x[62] > [1] 2.548991 > > > -pd         [[alternative HTML version deleted]] ______________________________________________ [hidden email] mailing list -- To UNSUBSCRIBE and more, see https://stat.ethz.ch/mailman/listinfo/r-helpPLEASE do read the posting guide http://www.R-project.org/posting-guide.htmland provide commented, minimal, self-contained, reproducible code.