【正文】
; (626) ( 3) . (627) 其中 與 、 與 分別為兩個(gè)樣本的樣本均值與樣本方差, 是‘合樣本’ ),( 121 nXXX ? ),(~ 211 ??NX ),( 221 nYYY ?)1 ,0(~)()(22212121 NnnYX????????22221 ??? ??)2(~)()( 21212121 ?????? nntnnnnSYXw??),1,1(~ 2122222121 ?? nnFSS??X21SY22Sw ,( 21 XX 1, nX? ), 221 nYYY ?的標(biāo)準(zhǔn)差,定義為 . (628) 2)1()1(21222211??????nnSnSnSw謝謝觀看 /歡迎下載 BY FAITH I MEAN A VISION OF GOOD ONE CHERISHES AND THE ENTHUSIASM THAT PUSHES ONE TO SEEK ITS FULFILLMENT REGARDLESS OF OBSTACLES. BY FAITH I BY FAITH