On 02-Mar-2012 IOANNA wrote: > Hello, > I run a linear regression I get the summary, e.g.: > >> > Call: > lm(formula = signal ~ conc) > Residuals: > 1 2 3 4 5 > 0.4 -1.0 1.6 -1.8 0.8 > Coefficients: > Estimate Std. Error t value Pr(>|t|) > (Intercept) 3.60000 1.23288 2.92 0.0615 . > conc 1.94000 0.05033 38.54 3.84e-05 *** > --- > Signif. codes: 0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1 > Residual standard error: 1.592 on 3 degrees of freedom > Multiple R-Squared: 0.998, Adjusted R-squared: 0.9973 > F-statistic: 1486 on 1 and 3 DF, p-value: 3.842e-0 > > I would like to call the probability of the t-test only in order > to use it separately. For example I 'd like to get: > Pr<-3.84e-05 > > Similarly I want to call the standard error of the parameters > and the function: > SEconc<-0.05033 > > I don't know how to do this. Any help? > > Regards, > Ioanna
Hi Ioanna, If you look at '?summary.lm' and read the section "Value", you will see that the returned value is a list with several components, one of which is: coefficients: a p x 4 matrix with columns for the estimated coefficient, its standard error, t-statistic and corresponding (two-sided) p-value. Aliased coefficients are omitted. This is effectively as displayed by summary(lm...)). So your Coefficients: > Estimate Std. Error t value Pr(>|t|) > (Intercept) 3.60000 1.23288 2.92 0.0615 . > conc 1.94000 0.05033 38.54 3.84e-05 *** (apart from the significance codes "." and "***") are the elements in this p=2 x 4 matrix. Hence summary(lm.r)$coef would give the full 4x4 matrix (you can abbreviate "coefficients" to "coef"), and so summary(lm.r)$coef[2,4] will give you the P-value for "conc", and summary(lm.r)$coef[2,2] will give the SE of the estimate of "conc". And so on. Ted. ------------------------------------------------- E-Mail: (Ted Harding) <ted.hard...@wlandres.net> Date: 02-Mar-2012 Time: 13:09:03 This message was sent by XFMail ______________________________________________ R-help@r-project.org 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.