| S.alba {drc} | R Documentation |
Data are from an experiment, comparing the potency of the two herbicides glyphosate and bentazone in white mustard Sinapis alba.
data(S.alba)
A data frame with 68 observations on the following 3 variables.
DoseHerbicideBentazone Glyphosate (the two herbicides applied).DryMatterThe lower and upper limits for the two herbicides can be assumed identical, whereas slopes and ED50 values are different (in the log-logistic model).
Christensen, M. G. and Teicher, H. B. and Streibig, J. C. (2003) Linking fluorescence induction curve and biomass in herbicide screening, Pest Management Science, 59, 1303–1310.
See the examples in the examples sections in drm and SI.
## Fitting a log-logistic model with ## common lower and upper limits S.alba.m1 <- drm(DryMatter~Dose, Herbicide, data=S.alba, fct = LL.4(), pmodels=data.frame(Herbicide,1,1,Herbicide), adjust="bc1") ## Plotting fitted regression curves together with the data plot(S.alba.m1)