An Introduction to the Study, Along with the Data and Methods Used

Introduction
   

2. METHODOLOGY AND DATA

In order to investigate the spatial distribution of the poorest counties in 
the United States an overall measure of poverty must be selected, and a 
spatially sensitive index was developed for the 1980 and 1990 analysis 
(Shaw 1996). Since lack of income is still seen as fundamental to poverty in 
the United States an income measure was used, but one which incorporates 
some spatial sensitivity to variations in the cost of living. Housing costs 
were adjusted for by developing a per capita income 'INDEX' for each county 
as follows:

(Median household income - Median housing costs)/Average number of persons per household

The necessary data to calculate INDEX have been stably available since the 
1980 census (U.S. Department of Commerce 1980; 1990; 2000; 2010) and so is 
used for this extended study. Incorporating median housing costs (which 
include mortgage payments, real estate taxes, insurance costs, and utilities), 
into INDEX provides a measure of poverty that is sensitive to spatial variations 
in the cost of living, unlike census data using the official poverty line. This 
income index for U.S. counties was mapped for 1980, 1990, 2000, and 2010 to 
explore the spatial distribution of poor and affluent counties. In addition, 
simple descriptive statistics are utilized to gain some understanding of changes 
in the geography of poverty and affluence over time.

INDEX 1980 data
INDEX 1990 data
INDEX 2000 data
INDEX 2010 data

States 1980 data
States 1990 data
States 2000 data
States 2010 data

References