# HELP relevel INTERCEPT-COMPARISONS

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## HELP relevel INTERCEPT-COMPARISONS

 Dear colleagues, How can I do to "relevel" the intercept? I need that the treatment "Db" be the intercept, and have p-values for the comparisons with the others treatments. I used the function "relevel" but it did not work out to have what I want. Thanks for your help, Xavier T1 <- read.table(file.choose(), h=T) > head(T1)   treatment replicate Time     Ebcg 1   CHA0+Db         1    1  9681172 2   CHA0+Db         2    1  5599000 3   CHA0+Db         3    1 10280480 4   CHA0+Db         4    1  1004526 5   CHA0+Db         5    1 12942018 6   CHA0+Db         6    1  7478773 > attach(T1) > summary(T1)    treatment   replicate          Time        Ebcg  CHA0   :6   Min.   :1.000   Min.   :1   Min.   :       0  CHA0+Db:9   1st Qu.:2.750   1st Qu.:1   1st Qu.: 1000922  Db     :9   Median :4.500   Median :1   Median : 4044094  Healthy:9   Mean   :4.625   Mean   :1   Mean   : 5699717  PCL    :6   3rd Qu.:6.250   3rd Qu.:1   3rd Qu.: 7785782  PCL+Db :9   Max.   :9.000   Max.   :1   Max.   :24736254 > hist(Ebcg) > treatment<-relevel(treatment,ref="Db") > mT1<-lm(sqrt(Ebcg)~treatment,data=T1) > summary(mT1) Call: lm(formula = sqrt(Ebcg) ~ treatment, data = T1) Residuals:      Min       1Q   Median       3Q      Max -1748.12  -540.19     0.97   545.14  1949.22 Coefficients:                                  Estimate         Std. Error     t value     Pr(>|t|) (Intercept)                     532.5          384.4       1.385         0.173296 treatmentCHA0+Db   2048.5          496.3       4.128         0.000170 *** treatmentDb                2491.9          496.3       5.021         9.93e-06 *** treatmentHealthy       1215.6          496.3       2.450         0.018552 * treatmentPCL                120.4          543.6       0.221         0.825816 treatmentPCL+Db        2098.9          496.3       4.229         0.000124 *** --- Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1 Residual standard error: 941.6 on 42 degrees of freedom Multiple R-squared:  0.5206,    Adjusted R-squared:  0.4635 F-statistic: 9.121 on 5 and 42 DF,  p-value: 6.227e-06 Xavier Chiriboga M. PhD Candidate Fundamental and Applied Research in Chemical Ecology Lab. Institute of Biology University of Neuchatel Website: https://www.unine.ch/farce/home/membres/xavier-chiriboga.html        [[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.