问题如下图:
如果样本量很大,但是non-normally distributed,是不是也可以当成是normal distributed,可以用参数检验,比如z或者t检验。
选项:
A.
B.
C.
解释:
NO.PZ2017092702000147 问题如下 analyst is examining the monthly returns for two fun over one year. Both fun’ returns are non-normally stribute To test whether the mereturn of one funis greater ththe mereturn of the other fun the analyst cuse: A.a parametric test only. B.a nonparametric test only. C.both parametric annonparametric tests. B is correct. There are only 12 (monthly) observations over the one yeof the sample anthus the samples are small. Aitionally, the fun’ returns are non-normally stribute Therefore, the samples not meet the stributionassumptions for a parametric test. The Mann–Whitney U test (a nonparametric test) couluseto test the fferences between population means这道题检验的是两个均值之间的关系。如果对应的两个总体都是正态分布的话,那么我们需要使用t检验,也就是参数检验(对于t检验而言,参数就是自由度)。但这道题为非正态总体“Both fun’ returns are non-normally stribute,所以t检验就不能用了。这个时候只能使用非参数检验。 非正态分布,样本足够大不是也可以用Z检验吗?
NO.PZ2017092702000147 问题如下 analyst is examining the monthly returns for two fun over one year. Both fun’ returns are non-normally stribute To test whether the mereturn of one funis greater ththe mereturn of the other fun the analyst cuse: A.a parametric test only. B.a nonparametric test only. C.both parametric annonparametric tests. B is correct. There are only 12 (monthly) observations over the one yeof the sample anthus the samples are small. Aitionally, the fun’ returns are non-normally stribute Therefore, the samples not meet the stributionassumptions for a parametric test. The Mann–Whitney U test (a nonparametric test) couluseto test the fferences between population means这道题检验的是两个均值之间的关系。如果对应的两个总体都是正态分布的话,那么我们需要使用t检验,也就是参数检验(对于t检验而言,参数就是自由度)。但这道题为非正态总体“Both fun’ returns are non-normally stribute,所以t检验就不能用了。这个时候只能使用非参数检验。 如题,谢谢
NO.PZ2017092702000147 问题如下 analyst is examining the monthly returns for two fun over one year. Both fun’ returns are non-normally stribute To test whether the mereturn of one funis greater ththe mereturn of the other fun the analyst cuse: A.a parametric test only. B.a nonparametric test only. C.both parametric annonparametric tests. B is correct. There are only 12 (monthly) observations over the one yeof the sample anthus the samples are small. Aitionally, the fun’ returns are non-normally stribute Therefore, the samples not meet the stributionassumptions for a parametric test. The Mann–Whitney U test (a nonparametric test) couluseto test the fferences between population means这道题检验的是两个均值之间的关系。如果对应的两个总体都是正态分布的话,那么我们需要使用t检验,也就是参数检验(对于t检验而言,参数就是自由度)。但这道题为非正态总体“Both fun’ returns are non-normally stribute,所以t检验就不能用了。这个时候只能使用非参数检验。 是说,图里这三个检验,都需要前提是两个样本符合正态分布?
NO.PZ2017092702000147 a nonparametric test only. both parametric annonparametric tests. B is correct. There are only 12 (monthly) observations over the one yeof the sample anthus the samples are small. Aitionally, the fun’ returns are non-normally stribute Therefore, the samples not meet the stributionassumptions for a parametric test. The Mann–Whitney U test (a nonparametric test) couluseto test the fferences between population means我记得视频中讲test参数的都可以用参数检验,如果是test排序、符号等问题的才需要非参数检验。这道题是不是虽然提到了mean,但是本质是要看mean的大小(也就是类似排序或者符号)所以要用非参数检验?
是不是所有学过的参数检验的前提就是一定要符合正态分布?不符合的就是非参数检验,这样理解对吗?