st: new version seqlogit available from SSC

[Maarten buis <maartenbuis@yahoo.co.uk>]

Thanks to Kit Baum a new version of -seqlogit- is now available from
SSC. -seqlogit- is intended to model a process that consist of a number
of steps, for example education that consists of a step whether or not
to finish primary education, whether or not one finishes secondary
education given that one finished primary education, and whether one
finishes tertiary education given that one finishes tertiary education.
-seqlogit- also alows for more complex decision trees, for example in 
some countries there is a branching point early on that separates
children between an academic and a vocational track.

The -seqlogit- package serves two purposes: 

1) it implements an decomposition proposed in Chapter 6 of Buis (2010),
whereby the effect of a variable on the final outcome of the process 
is decomposed as a weighted sum of the effects on passing each stage 
and a weight assigned to these stages. 

2) This model can potentially be more sensitive to unobserved 
heterogeneity than other models. -seqlogit- allows you to estimate the 
effects for many different types of scenarios concerning unobserved 
heterogeneity, as was proposed in Chapter 7 of Buis (2010). This way 
one can determine whether this is an issue for your data and the 
hypotheses that you want to test.  Moreover, if you find that 
unobserved heterogeneity is a problem, these scenarios help you to 
choose between possible models for correcting for it, as it will 
indicate what kind of aspects are important. For example do we need to 
worry about the possible correlation between the unobserved variables 
and the observed variables during the first transition, or can we use 
a random-effects-type model (which assumes that this correlation is
0).

This update has increased the number of scenarios that can be estimated
with -seqlogit-

To install it type in Stata:
ssc install seqlogit, replace

or:
adoupdate, update

-- Maarten

Buis, M.L. (2010) "Inequality of Educational Outcome and Inequality 
of Educational Opportunity in the Netherlands during the 20th Century"
PhD thesis. Amsterdam: VU University Amsterdam.
<http://www.maartenbuis.nl/dissertation>

--------------------------
Maarten L. Buis
Institut fuer Soziologie
Universitaet Tuebingen
Wilhelmstrasse 36
72074 Tuebingen
Germany

http://www.maartenbuis.nl
--------------------------


      

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