This is discussed in this thread: http://tolstoy.newcastle.edu.au/R/e2/help/07/01/9353.html
This mostly goes over the ground discussed here plus there is a do.call based solution there too. On Feb 1, 2008 7:10 AM, john seers (IFR) <[EMAIL PROTECTED]> wrote: > > > > Thanks for the help. > > Regards > > > John Seers > > > --- > -----Original Message----- > From: Peter Dalgaard [mailto:[EMAIL PROTECTED] > Sent: 01 February 2008 10:04 > To: [EMAIL PROTECTED] > > Cc: john seers (IFR); [EMAIL PROTECTED] > Subject: Re: [R] Building a formula using paste > > [EMAIL PROTECTED] wrote: > > use as.formula() rather than just formula(). > > > > > > > Hm? > > That doesn't seem to cut it for me: > > > f <- as.formula(y~x) > > lm(f) > > Call: > lm(formula = f) > > Coefficients: > (Intercept) x > 0.06437 -0.09714 > > > summary(lm(f)) > > Call: > lm(formula = f) > > Residuals: > Min 1Q Median 3Q Max > -1.2780 -0.4229 -0.3208 0.7534 1.3073 > > Coefficients: > Estimate Std. Error t value Pr(>|t|) > (Intercept) 0.06437 0.61961 0.104 0.920 > x -0.09714 0.09986 -0.973 0.359 > > Residual standard error: 0.907 on 8 degrees of freedom > Multiple R-Squared: 0.1058, Adjusted R-squared: -0.005995 > F-statistic: 0.9464 on 1 and 8 DF, p-value: 0.3591 > > <etc.> > > The problem is that we get the call and not the formula, and this appears to > be the case whether you use formula or as.formula. Also > > > identical(as.formula(y~x), formula(y~x)) > [1] TRUE > > I see two workarounds: > > (a) Extract the formula explicitly and print it along with the output > > > formula(m) > y ~ x > > m > > Call: > lm(formula = f) > > Coefficients: > (Intercept) x > 0.06437 -0.09714 > > (b) substitution tricks, e.g. > > > eval(bquote(lm(.(f)))) > > Call: > lm(formula = y ~ x) > > Coefficients: > (Intercept) x > 0.06437 -0.09714 > > > > > > Hi All > > > > I have looked but cannot find an answer to this. > > > > I want to build a formula dynamically (in a function), using for > > example paste, and using it in a model: > > > > fr<-"F1" > > f1<-formula(paste(fr, "~ SensoryTerm")) > > m1<-aov(f1, data=vdata) > > > > So this is the equivalent of m1<-aov(F1 ~ SensoryTerm, data=vdata) > > > > This works fine but the problem is the formula appears as "f1" in the > > summary(m1) of the model and not "F1 ~ SensoryTerm". With many models > > this can be a bit confusing .... > > > > Is there a way to code this so the formula appears in the model summary? > > > > > > > > > -- > O__ ---- Peter Dalgaard Øster Farimagsgade 5, Entr.B > c/ /'_ --- Dept. of Biostatistics PO Box 2099, 1014 Cph. K > (*) \(*) -- University of Copenhagen Denmark Ph: (+45) 35327918 > ~~~~~~~~~~ - ([EMAIL PROTECTED]) FAX: (+45) 35327907 > > ______________________________________________ > 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. > ______________________________________________ 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.
