On Sat, 31 Aug 2013 19:48:13 -0500, F. George McDuffee
wrote:

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http://www.pbs.org/newshour/business...destiny-w.html
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The recent release of a new economic mobility study that
was featured on PBS NewsHour brings much-needed evidence on
the difficulty of getting ahead in the United States.

The study is important not just because it suggests how
limited opportunities for mobility are in the United States.
What's new is the finding that the neighborhoods in which
children grow up affect their opportunities for mobility.
The study suggests that poor children who grow up in
communities like Detroit that don't provide income
supplements for poor working families are less likely to
escape poverty than those who grow up in places like San
Jose in which relatively generous supplements are provided.
It's difficult to get ahead, in other words, if one is so
unlucky as to be born into an ungenerous community.
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I have received several emails on this. Be reminded that it
was the relative size or fraction of the urban areas
population that was middle class, not the absolute size of
the middle class population or the urban area that seemed to
have an effect.

Grandma had two adages which encapsulated these findings:

(1) Birds of a feather flock together; and
(2) You become like the people you associate with.

If a higher fraction of the areas population, where you
live, is middle class, the more likely you are to associate
with and absorb middle class values and social skills from
your peers, and the more likely it is your parents are at
least lower middle class if you are living in a middle class
enclave.

Technically this appears to be a predictive and not a causal
factor.