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Spss中LSD是什么意思?进行单因素方差分析两两比较是,出现LSD和Bonferroni两组数据,该看哪一组?

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Spss中LSD是什么意思?进行单因素方差分析两两比较是,出现LSD和Bonferroni两组数据,该看哪一组?
SSPS软件对LSD和Bonferroni的解释如下:
•LSD. Uses t tests to perform all pairwise comparisons between group means. No adjustment is made to the error rate for multiple comparisons. Used for pairwise comparison. This test does not control the overall probability of rejecting the hypotheses that some pairs of means are different, while in fact they are equal.
•Bonferroni. Uses t tests to perform pairwise comparisons between group means, but controls overall error rate by setting the error rate for each test to the experimentwise error rate divided by the total number of tests. Hence, the observed significance level is adjusted for the fact that multiple comparisons are being made. Used for pairwise comparison.
不难看出,LSD仅对所有的多重比较进行简单的多次t检验,不对单个检验的显著水平进行任何校正(以保证总拒绝率),因此它的结果仅能作一般参考,实际应用意义不大;Bonferroni是SSPS软件经常使用的一种多重比较的校正方法,它也是对所有的多重比较进行多次t检验,但它单个检验的显著水平进行校正,当比较的组数不是太多的话,使用Bonferroni还是不错的.不过,当比较的组数太大时,Bonferroni显得比较保守.