这题哪里说是关联的了？能否解释一下。
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No.PZ2018062016000143 (选择题)
来源: 品职出题
Claire payed close attention to two portfolios specializing in stocks. The two portfolios were nearly in risk(measured by standard deviation of return) during 2013-2017. Claire believed that the mean monthly return difference between the two portfolio equal to zero and gathered the data of mean monthly retun of two portfolios from 2013-2017. In order to test the hypothesis that the mean monthly return on two portfolios equal from 2013-2017, which of the following test statistic is most appropriate?
您的回答, 正确答案是: A
A
a paired comparisons t-test.
B
不正确an approximate t-test of mean differences between the two populations.
C
a t-test of the difference between the two population means.
数据统计(全部)
做对次数: 980
做错次数: 364
正确率: 72.92%
数据统计(个人)
做对次数: 0
做错次数: 1
正确率: 0.00%
解析
A is correct. The two portfolios have the same series of risk factors, so their returns were not independent. Besides, the data is arranged in paired observations. We choose the paired comparisons t-test.
