Re: st: how to do a weighted transition matrix

[Hey Sky <heyskywalker@yahoo.com>]

Dear Nick

thanks for your reply. 

my research topic is about the transition probability from one state to another, 
e.g., white/blue collar job and self-employment within an unbalanced panel. all 
the three states are mutural exclusive dummy variables. the weight is a constant 
number but not integer. it adjust the percentage of different people groups, 
e.g., there is too many refugee in the survey but less other immigrants so that 
the stats bureau uses the weight to adjust it back to represent the  real world. 


the following created data are almost the same with the actural one, though I am 
not sure about the value of the weight. I checked it once long time ago and 
vaguely remember it is just a constant number (I cannot check not due to the 
data is not at hand). I used xttrans to get the transition matrix but I have 
been required to use weights otherwise I cannot take the results to the public. 


hope I make my question clear and thanks for any suggetsions. 

clear
input id time w b s weight
1 1 1 0 0 1.8
1 2 1 0 0 1.8
1 3 0 1 0 1.8
2 1 0 1 0 1.8
2 2 0 1 0 1.8
2 3 0 0 1 1.8
3 1 0 0 1 1.8
3 2 0 1 0 1.8
3 3 . . .  1.8
4 1 0 0 1 1.8
4 2 0 1 0 1.8
4 3 1 0 0 1.8
end


Nan 
from Montreal




----- Original Message ----
From: Nick Cox <njcoxstata@gmail.com>
To: statalist@hsphsun2.harvard.edu
Sent: Fri, April 29, 2011 12:06:46 PM
Subject: Re: st: how to do a weighted transition matrix

More explanation would help. Where do the weights come from? Do they
weight the transitions? The earlier state? The later state? Are they
integers or not? What is your data structure? Which variables hold
which information? Do you expect a precise answer to a vague question?

At its easiest, this sounds like a transition matrix multiplied
elementwise by a weights matrix, so save the matrices independently
and do the multiplication in Mata.

Nick

On Fri, Apr 29, 2011 at 4:57 PM, > Nan from Montreal, a.k.a. Hey Sky
<heyskywalker@yahoo.com> wrote:

> I have to do a weighted transition matrix but it is not an option for the
> command xttrans.
>
> I have searched the archives but did not find any discussion about
> this question.
> did anyone experience this before and any (other) method to deal with it?

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