Re: st: Looking up values in a 2 dimensional table

[David Kantor <kantor.d@att.net>]

At 06:26 PM 4/17/2008, Mike Lacy wrote:
> A colleague of mine has a data file with family income and family 
> size for a large sample, with real family income for each of a 
> series of years, in the wide format, e.g., something like:
>
> famid FamSize1985 FamSize1987 FamSize1991 ... Inc1985 inc1987 Inc1991 ...
>
> with family sizes and family incomes recorded for about 20 different 
> year, not at fixed intervals.
>
> He needs to create a poverty status indicator corresponding to each 
> year, based on a 2 dimensional table giving poverty thresholds for 
> each value of year and family size.  All the ways I can imagine 
> doing this seem relatively clumsy. (Among other things, I thought 
> about ways of doing this with a matrix but they would require using 
> the value of the family size variable as an index into the matrix, 
> which is beyond my ken.)
> I also considered something involving reshape and merge, but that 
> seemed awkward as well.
>
> Suggestions?
> [...]
First, you probably mean Poverty Guideline.
Poverty Guideline is a simple, rough calculation based on family 
size, income, and year.
Poverty Threshold is a more complex calculation that considers number 
of children and number of elderly in addition to the other factors. 
It is the "officially correct" measure, but is more complicated to compute.

Those are U.S. government standards. (USDA, I believe.)

I have ado files to calculate both of these. But for the threshold, 
it works for 1997 & 1998 only.
For the guideline, it does 1982-2007.

Either of them can be "filled in" to handled other years. (And BTW, 
the poverty guideline program uses a matrix.)

Write me privately if you want these. But note that there are no help 
files yet.
--David Kantor
kantor.d@att.net


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