Statalist The Stata Listserver

[Date Prev][Date Next][Thread Prev][Thread Next][Date index][Thread index]

st: RE: how to choose between geographical identifiers??

From   "Nick Cox" <>
To   <>
Subject   st: RE: how to choose between geographical identifiers??
Date   Wed, 8 Mar 2006 23:29:16 -0000

I am a geographer but I don't know much about (what is 
usually called human) geography. I regarded it as my main field 
of interest between 1968 and 1969, but no longer. There aren't 
many geographers on this list, I think. 

However, your question is not really geographical. I guess
from this that you are using lots of dummies in each case 
and for once the answer is whichever set of dummies gives
you a better model, according to your criteria of model 
excellence (my favourite criterion is usually minimal 
structure in residuals). 

In broad terms both LADs and TTWAs are fairly heterogeneous
as both spring from a idea of an area functioning together
rather than formal similarity of anything. So knowing the 
area might not help enormously in predicting wage. But 
whichever spatial subdivision has a finer mesh should 
prove better. 


Ada Ma
> I have a bunch of wage observations and all the observations are
> attached with two geographical identifiers - local authority districts
> (LADs) and travel to work areas (TTWAs).  I want to find out how wages
> vary across different areas in UK.
> Now I can run wage estimations using either one of the two categorical
> variables as explanatory variable.  I would however like to find out
> which categorical variable fits the data better.  How do I compare the
> two sets of results given that the explanatory variables are quite
> different?
> Could you recommend what kind of tests I should use and if you are a
> geographer, could you tell me are there any criteria that are used by
> geographers to choose between different definitions of geographies
> (regions, as opposed to LADs, as opposed to TTWAs, etc.)

*   For searches and help try:

© Copyright 1996–2021 StataCorp LLC   |   Terms of use   |   Privacy   |   Contact us   |   What's new   |   Site index