On Wed, Jul 13, 2011 at 03:27:10PM +0200, Jira, Marcel wrote: > Hi! > > Let's consider I have a table like this > > id qualification gender age income > > I'd like to select (for example 100) lines of this table by random, but the > random mechanism has to follow a certain probability distribution. > > I want to use this procedure to construct a test group for another selection. > > Example: > > I filter all lines having the qualification "plumber". > I get 50 different ids consisting of 40 males, 10 females and a certain age > distribution. > > I also get some information concerning the income of the plumbers. > > Now I want to know if the income is more influenced by the gender and age > distribution or by the qualification "plumber". > > Therefore I would like to select a test group (of 50 or more) without any > plumbers. This test group has to follow the same age and gender distribution. > > Then I would be able to compare this groups income statistics with the > plumbers income statistics. > > Is this possible (and doable with reasonable effort) in PostgreSQL? > > Thank you in advance. > > Best regards, > > Marcel Jira >
You may want to take a look at pl/R which make the R system available to PostgreSQL as a function language. Regards, Ken -- Sent via pgsql-sql mailing list (pgsql-sql@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-sql
