Re: [Gretl-devel] bandwidth default for nadarwat()

On Thu, 14 Jun 2018, Sven Schreiber wrote: > Am 14.06.2018 um 07:17 schrieb Riccardo (Jack) Lucchetti: >> On Wed, 13 Jun 2018, Sven Schreiber wrote: >> >>> I don't see why we need to rename and deprecate the nadarwat >>> function to achieve what you want. In the old version the user >>> always has to give y, x and h (bandwidth). Plus in the background >>> there is the nadarwat_trim setting (default 4). >>> >>> So if we extend the function as you say, then only two things need >>> to be done internally if the function is called with only the first >>> three args: >>> 1) Check whether bandwidth is negative. If so, set leave_one_out to >>> 1 and bandwidth to abs(bandwidth). >>> 2) Check whether the nadarwat_trim value is != 4. If so, set the >>> trim arg to that value. >> >> My concern is: how do you get automatic bandwidth selection and the >> leave-one-out option together? I guess that, in your scheme, you >> could leave the third argument empty and set the fourth one to 1, >> but it looks sort of awkward to me. Anyway, it's a possibility.

Ok, something like <hansl> function series nadwat(seties y, series x, scalar bandwidth[0],     bool leave_one_out[0], scalar trim[4])

> and also you put the default for leave_one_out to 0 whereas verbally > it sounds as if you want to have 1. So this is confusing. I have no strong opinion on this. Either 0 and 1 are equally tenable default values, in my opinion.