topic Re: Life Distribution: Fixing p and fixing Weibull beta in DS Weibull and solving only for Weibull a in Discussions

Life Distribution: Fixing p and fixing Weibull beta in DS Weibull and solving only for Weibull alpha

galactus3000 — Mon, 28 Aug 2017 14:05:54 GMT

Life Distribution: Fixing p and fixing Weibull beta in DS Weibull and solving only for Weibull alpha

Is there an easy way to fix n of n + m Life Distribution parameters and solve only for the remaining m parameters.

Thanks.

galactus3000

Re: Life Distribution: Fixing p and fixing Weibull beta in DS Weibull and solving only for Weibull a

David_Burnham — Mon, 28 Aug 2017 14:28:54 GMT

Once you have fitted a distribution you have an outline called "Parametric Estimate - <Dist Name>".

The red triangle hotspot for this outline has an option Fix Parameter. When you select this, below your profiler outline a second row of profilers appears (the outline name is Fix Parameter). There are some fields and checkboxes that allow you to specify and lock parameter values then update the other parameter estimates.

Re: Life Distribution: Fixing p and fixing Weibull beta in DS Weibull and solving only for Weibull a

galactus3000 — Mon, 28 Aug 2017 14:37:32 GMT

Bonus Question ... if I have three flavors of Life Distribution data, A, B and C, of common origin but different stress conditions, I might want to 'constrain' parameter p to be common all three, p=pA = pB = pC and likewise for b=bA=bB=bC, fitting the two (rather than six) parameters across the three datasets, while allowing for and fitting to unique values for parameters aA aB and aC

Thus fitting for 5 parameters rather than 9

Re: Life Distribution: Fixing p and fixing Weibull beta in DS Weibull and solving only for Weibull a

David_Burnham — Mon, 28 Aug 2017 15:42:14 GMT

you're welcome ;)