There are many different population indexes around population mixing. I don't know them all myself because I am not a demographer (even though I work and socialize with them). The index you are talking about is some integration index (based on differences within a population).
The dissimilarity index is based on lack of mixing within a given area/city. The difference from the overall area mix and the mix in the tracts that make up the overall area. For example, take two cities (Stripeytown and Rock Solid) with two populations (stripes and solids to be absurd). Stripeytown is 90% stripey. Domea Solid is 50/50. Domea Solid is more integrated using the "integration index" but we need more information to determine integration by the "dissimilarity index" (and what people then refer to as segregation).
Let's say each city is divided into 10 tracts. All ten of Stripeytown's tracts are 90% stripey and 10% solid. This gives Stripeytown a perfect 0 on the dissimilarity index and is thus deemed perfectly integrated. Domea Solid's has 5 tracts that are 100% stripey and 5 tracts that are 100% solid. This gives Domea Solid a perfect 100 on the dissimilarity index and is thus deemed perfectly segregated.
Peace,
Jim
At 02:53 PM 5/10/01, Charles Brown wrote:
>CB: I'm trying to think how they draw the census tracts and whether if
>drawn differently , there would be a different result.
>
>What about all the cities with very small %'s of Black people ? Aren't
>they often very segregated almost automatically by the fact that most of
>the whites can't live near many Blacks ?
When quinces become pomegranates You become mine
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