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Weighting in Apollo

Ask questions about how to estimate models and how to change your settings for estimation.
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KKWells
Posts: 2
Joined: 04 Dec 2023, 22:45

Weighting in Apollo

Post by KKWells »

Hi Stephane and David,

Can you provide more information on how weights are applied during estimation when using the apollo_weighting function? I understand how to tell Apollo to use weights, but it is unclear how those weights are used once provided.

Best,
Kaylee

p.s. Thank you for creating this package and continuing to develop and maintain it. The time and effort you have devoted and continue to devote to the package and this community is amazing and much appreciated.
stephanehess
Site Admin
Posts: 998
Joined: 24 Apr 2020, 16:29

Re: Weighting in Apollo

Post by stephanehess »

Hi

in simple terms, the contribution to the likelihood at the observation level (in cross-sectional specifications) or person level (in panel specifications) is taken to the power of w, where w is the weight. This is then equiavalent to multiplying the log-likelihood contribution by w

Does this answer your question

Stephane
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Stephane Hess
www.stephanehess.me.uk
KKWells
Posts: 2
Joined: 04 Dec 2023, 22:45

Re: Weighting in Apollo

Post by KKWells »

Yes! Thanks!
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