Hi > On Nov 24, 2016, at 10:49 AM, Attila Kinali <att...@kinali.ch> wrote: > > On Thu, 24 Nov 2016 08:16:08 -0500 > Bob Camp <kb...@n1k.org> wrote: > >> If you take the bad aging (out of spec) parts out of the pile, those are the >> ones >> with the best fit. They have very pretty curves and they stick to those >> curves >> for a *long* time. They have a single dominant cause for their aging ( = the >> defect). >> The rest of the parts have all of the causes bashed down by the process so >> that >> over a 20 or 30 year span, there probably is no single dominant cause. > > Then the question becomes: What would be a good fitting function for > the typical application of an OCXO that is regularly measured with > not too long time spans (e.g. GPSDO)? From the discussion it seems > that a second or third order Taylor would be sufficient to capture > aging for a span of 10-100 days.
Simple answer no. More complex answer: what are you trying to do? Depending on the answer to that there may be other functions that are useful. In general an unconstrained polynomial is great for fitting the data you have and awful for predicting the future. Bob > > Attila Kinali > > -- > It is upon moral qualities that a society is ultimately founded. All > the prosperity and technological sophistication in the world is of no > use without that foundation. > -- Miss Matheson, The Diamond Age, Neil Stephenson > _______________________________________________ > time-nuts mailing list -- time-nuts@febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. _______________________________________________ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
