T分布 java实现t检验过程，是对两样本均数(mean)差别的显著性进行检验。惟t检验须知道两个总体的方差(Variances)是否相等；t检验值的计算会因方差是否相等而有所不同。也就是说，t检验须视乎方差齐性(Equality of Variances)结果。所以，SPSS在进行t-test for Equality of Means的同时，也要做Levene"s Test for Equality of Variances 。
SHOW FULL COLUMNS FROM `jrk_downrecords` [ RunTime:0.002427s ]
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SHOW FULL COLUMNS FROM `jrk_member` [ RunTime:0.002015s ]
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SHOW FULL COLUMNS FROM `jrk_searchrecords` [ RunTime:0.001925s ]
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