Spencer Graves
2016-Aug-07 19:03 UTC
[Rd] problem with abine(lm(...)) for plot(y~x, log='xy')
Hello: In the following plot, the fitted line plots 100 percent above the points: tstDat <- data.frame(x=10^(1:3), y=10^(1:3+.1*rnorm(3))) tstFit <- lm(log(y)~log(x), tstDat) plot(y~x, tstDat, log='xy') abline(tstFit) I can get the correct line with the following: tstPredDat <- data.frame(x=10^seq(1, 3, len=2)) tstPred <- predict(tstFit, tstPredDat) lines(tstPredDat$x, exp(tstPred)) I tried "abline(tstFit)" hoping it would work. If the error had not been so obvious, I might not have noticed it. Thanks for your work to build a better R (and through that a better world). Spencer Graves
peter dalgaard
2016-Aug-07 19:21 UTC
[Rd] problem with abine(lm(...)) for plot(y~x, log='xy')
Try log10()... -pd> On 07 Aug 2016, at 21:03 , Spencer Graves <spencer.graves at prodsyse.com> wrote: > > Hello: > > > In the following plot, the fitted line plots 100 percent above the points: > > > tstDat <- data.frame(x=10^(1:3), y=10^(1:3+.1*rnorm(3))) > tstFit <- lm(log(y)~log(x), tstDat) > plot(y~x, tstDat, log='xy') > abline(tstFit) > > > I can get the correct line with the following: > > > tstPredDat <- data.frame(x=10^seq(1, 3, len=2)) > tstPred <- predict(tstFit, tstPredDat) > lines(tstPredDat$x, exp(tstPred)) > > > I tried "abline(tstFit)" hoping it would work. If the error had not been so obvious, I might not have noticed it. > > > Thanks for your work to build a better R (and through that a better world). > > > Spencer Graves > > ______________________________________________ > R-devel at r-project.org mailing list > https://stat.ethz.ch/mailman/listinfo/r-devel-- Peter Dalgaard, Professor, Center for Statistics, Copenhagen Business School Solbjerg Plads 3, 2000 Frederiksberg, Denmark Phone: (+45)38153501 Office: A 4.23 Email: pd.mes at cbs.dk Priv: PDalgd at gmail.com