Home Forums Article Discussions Article Discussions by Author Discuss content posted by Chris Nowicki Random problems RE: Random problems

  • June 9, 2009 at 8:53 am

    #1006753

    vzurkowski (6/9/2009)

    To "chose at random from 1,..,5" usually means to chose from 1,..,5 in such a way that any outcome has the same probability of being selected.

    Assuming T-SQL RAND() has good statistical properties (if someone knows of tests, please let me know), why would RAND(CHECKSUM(NEWID()) have good properties? (i.e.: why would it select a number uniformly distributed between 0 and 1 ?)

    Why wouldn't it? You're giving it a random seed.

    --Jeff Moden

    RBAR is pronounced "ree-bar" and is a "Modenism" for Row-By-Agonizing-Row.
    First step towards the paradigm shift of writing Set Based code:
    ________Stop thinking about what you want to do to a ROW... think, instead, of what you want to do to a COLUMN.

    Change is inevitable... Change for the better is not.

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