Testing if there is a dose effect at all
A significance test is provided for the comparison of the dose-response model considered and the simple linear regression model with slope 0 (a horizontal regression line corresponding to no dose effect)
noEffect(object)
object |
an object of class 'drc'. |
Perhaps useful for screening purposes.
The likelihood ratio test statistic and the corresponding degrees of freedom and p-value are reported.
Christian Ritz
ryegrass.LL.4 <- drm(rootl ~ conc, data = ryegrass, fct = LL.4()) noEffect(ryegrass.LL.4) # p-value < 0.0001: there is a highly significant dose effect!
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