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Correlation between random parameters

Ask questions about post-estimation functions (e.g. prediction, conditionals, etc) or other processing of results.
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Andy
Posts: 9
Joined: 26 Aug 2020, 12:59

Correlation between random parameters

Post by Andy »

Dear Stephane Hess,

In the manual, it is stated that the correlation of random parameters can be calculated using apollo_unconditionals. I wonder if there is an example that shows the code for calculating the correlations.

Kind regards
Andy
stephanehess
Site Admin
Posts: 998
Joined: 24 Apr 2020, 16:29

Re: Correlation between random parameters

Post by stephanehess »

Hi

yes, this is easy. Using example 15, you could do:

Code: Select all

> unconditionals=apollo_unconditionals(model,apollo_probabilities,apollo_inputs)
Unconditional distributions computed

> draws=do.call(cbind,lapply(unconditionals,as.vector))
> cor(draws)
          b_tt      b_tc      b_hw      b_ch
b_tt 1.0000000 0.6140231 0.4796923 0.5666015
b_tc 0.6140231 1.0000000 0.3210298 0.3833275
b_hw 0.4796923 0.3210298 1.0000000 0.6651674
b_ch 0.5666015 0.3833275 0.6651674 1.0000000
Hope this helps

Stephane
--------------------------------
Stephane Hess
www.stephanehess.me.uk
Andy
Posts: 9
Joined: 26 Aug 2020, 12:59

Re: Correlation between random parameters

Post by Andy »

Dear Stephane,

Thank you very much. This is an elegant solution and helps a lot.

Best regards
Andy
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