[R] probit etc. for dose-response modeling

Thomas Lumley
Tue, 27 Aug 2002 15:53:40 -0000

On Tue, 27 Aug 2002, Johannes Ranke wrote:

> Hello all
>
> I have done some fitting of pnorm functions to dose-response data, so I
could
> calculate EC50 values (dose where the response is 0.5). I used the nlm
function
> for this, so I did not get any information about the confidence intervals
of
> the fitted parameters.
>
> What would be a good way to do such a probit fit, or is there a package
which I
> could use?

Probit models are generalised linear models so you can use glm().

	-thomas