Re: [R] how to interpolate a plot with a logistic curve

2007-12-06 Thread Simone Gabbriellini
Dear Christian, it works great, and it is simple to understand, thank you very much. just a detail, is it possible to plot just the fitted curve and not the data? it's because I would like to have data in black and the fitted curve in red.. I don't know how to pick up the single parts, if I

Re: [R] how to interpolate a plot with a logistic curve

2007-12-06 Thread Simone Gabbriellini
Dear Christian, it works great, and it is simple to understand, thank you very much. just a detail, is it possible to plot just the fitted curve and not the data? it's because I would like to have data in black and the fitted curve in red.. I don't know how to pick up the single parts, if I

Re: [R] how to interpolate a plot with a logistic curve

2007-12-06 Thread Christian Ritz
Dear Simone, you can use the package 'drc' to fit a logistic model, that is a non-linear regression model based on the equation c+(d-c)/(1+exp(b(x-e))), to your data (below named 'simone'): ## Fitting a 4-parameter logistic model (also called Boltzmann model) simone.m1 <- drm(size~x, data=sim

Re: [R] how to interpolate a plot with a logistic curve

2007-12-05 Thread Dylan Beaudette
On Wednesday 05 December 2007, Simone Gabbriellini wrote: > hello, > > I have this simple question. This is my dataset > > size > 1 57 > 2 97 > 3 105 > 4 123 > 5 136 > 6 153 > 7 173 > 8 180 > 9 193 > 10202 > 11213 > 12219 > 13224 > 14224