Recent content by purnej

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    deriving chi-square stat for contingency table

    Howdy! I'm attempting to derive the chi-square stat for a 2x2 contingency table, like: a | b ------ c | d The chi-square formula given is : (a+b+c+d)(ad- bc)^2 / ( (a+b)(a+c)(b+d)(c+d) ) I can derive all but the (ad-bc)^2 part of the formula. Any links or tips about how this formula...