According to stats-wonk Matthew Ladner, the answer is: most of it.
Here is his first post, on Jay P Greene’s blog.
Gentrification is the primary driver of District of Columbia Academic Gains
How much of the NAEP gains in DC come from gentrification?
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Ladner is a voucher cheerleader as is Jay Greene
Diane
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Given that, the fact that he points out the glaring gap is more merit-worthy.
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