Mike, I kind of have the same question. What if for a mixed effect model, say using lme(), how to specify the interaction effect (between a fixed effect and a random effect)? and where to find the result of the interaction? Thanks.
Jun On Thu, Apr 16, 2009 at 12:08 PM, Mike Lawrence <mike.lawre...@dal.ca>wrote: > summary(my_lm) will give you t-values, anova(my_lm) will give you > (equivalent) F-values. summary() might be preferred because it also > provides the estimates & SE. > > > a=data.frame(dv=rnorm(10),iv1=rnorm(10),iv2=rnorm(10)) > > my_lm=lm(dv~iv1*iv2,a) > > summary(my_lm) > > Call: > lm(formula = dv ~ iv1 * iv2, data = a) > > Residuals: > Min 1Q Median 3Q Max > -1.8484 -0.2059 0.1627 0.4623 1.0401 > > Coefficients: > Estimate Std. Error t value Pr(>|t|) > (Intercept) -0.4864 0.4007 -1.214 0.270 > iv1 0.8233 0.5538 1.487 0.188 > iv2 0.2314 0.3863 0.599 0.571 > iv1:iv2 -0.4110 0.5713 -0.719 0.499 > > Residual standard error: 1.017 on 6 degrees of freedom > Multiple R-squared: 0.3161, Adjusted R-squared: -0.02592 > F-statistic: 0.9242 on 3 and 6 DF, p-value: 0.4842 > > > anova(my_lm) > Analysis of Variance Table > > Response: dv > Df Sum Sq Mean Sq F value Pr(>F) > iv1 1 1.9149 1.9149 1.8530 0.2223 > iv2 1 0.4156 0.4156 0.4021 0.5494 > iv1:iv2 1 0.5348 0.5348 0.5175 0.4990 > Residuals 6 6.2004 1.0334 > > > On Thu, Apr 16, 2009 at 10:35 AM, kayj <kjaj...@yahoo.com> wrote: > > > > Hi, > > > > > > How can I find the p-value for the F test for the interaction terms in a > > regression linear model lm ? > > > > I appreciate your help > > > > > > -- > > View this message in context: > http://www.nabble.com/F-test-tp23078122p23078122.html > > Sent from the R help mailing list archive at Nabble.com. > > > > ______________________________________________ > > 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. > > > > > > -- > Mike Lawrence > Graduate Student > Department of Psychology > Dalhousie University > > Looking to arrange a meeting? Check my public calendar: > http://tr.im/mikes_public_calendar > > ~ Certainty is folly... I think. ~ > > ______________________________________________ > 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. > -- Jun Shen PhD PK/PD Scientist BioPharma Services Millipore Corporation 15 Research Park Dr. St Charles, MO 63304 Direct: 636-720-1589 [[alternative HTML version deleted]] ______________________________________________ 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.
