Re: [Gretl-users] threshold value
On Fri, 19 Sep 2014, Riccardo (Jack) Lucchetti wrote:
On Fri, 19 Sep 2014, Artur Bala wrote:
> Dear all,
> Does anyone know how the threshold value for the predicted probalities in a
> logit/probit estimation is being calculated in gretl?
I assume that by "threshold" you mean "the value of P(x'b) at which we
shwitch from predicting a 0 to predicting a 1". I haven't looked at the
source code, but I'm pretty sure it's 0.5. Why should it be anything else?
Try this:
<hansl>
open mroz87 --quiet
logit LFP const WA WE KL6
series pred = $yhat>0.5
xtab LFP pred
</hansl>
Yes. In the source (discrete.c) the criterion for predicting a 1 is x'b
greater than 0, which is of course equivalent to $yhat>0.5.
Allin Cottrell