Faster estimation of a discrete-time proportional hazards model with gamma frailty

Fitting a complementary log–log model that accounts for gamma-distributed unobserved heterogeneity often takes a significant amount of time. This is in part because numerical derivatives are used to approximate the gradient vector and Hessian matrix. The main contribution of this article is the use of Mata and a gf2 evaluator to express the gradient vector and Hessian matrix. Gradient vector expression allows one to use a few different options and postestimation commands. Furthermore, expression of the gradient vector and Hessian matrix increases the speed at which a likelihood function is maximized.


Issue Date:
2012
Publication Type:
Journal Article
DOI and Other Identifiers:
st0256 (Other)
PURL Identifier:
http://purl.umn.edu/208005
Published in:
Stata Journal, Volume 12, Number 2
Page range:
242-256
Total Pages:
17

Record appears in:



 Record created 2017-04-01, last modified 2017-08-22

Fulltext:
Download fulltext
PDF

Rate this document:

Rate this document:
1
2
3
 
(Not yet reviewed)