Re: MCV lists for highly skewed distributions

From: John Naylor <jcnaylor(at)gmail(dot)com>
To: Simon Riggs <simon(at)2ndquadrant(dot)com>
Cc: Jeff Janes <jeff(dot)janes(at)gmail(dot)com>, pgsql-hackers <pgsql-hackers(at)postgresql(dot)org>
Subject: Re: MCV lists for highly skewed distributions
Date: 2018-01-20 05:00:15
Message-ID: CAJVSVGX9G4vUXiGL1yZxakiQT8dNv3do7Jm_xC7EHZ3rqZP6rw@mail.gmail.com
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I wrote:
> FWIW, I suspect that a solution
> that doesn't take into account a metric like coefficient of variation
> will have the wrong behavior sometimes, whether for highly uniform or
> highly non-uniform distributions.

By this I meant the coefficient of variation of the class size in the
sample, as denoted by gamma in the Haas and Stokes paper on page 7.

-John Naylor

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