NO.PZ2022123001000093
问题如下：
An analyst wants to estimate the return on the S&P 500 Index for
the current year using the following data and assumptions:
Sample size = 50 stocks from
the index.
Mean return for those stocks in
the sample for the previous year = 0.114.
Variance
= 0.0529.
The reliability factor for a
95% confidence interval with unknown population variance and sample size
greater than 30 is z.025=
1.96.
If
he assumes that the S&P 500 return this year will be the same as it was
last year, which of the following is the best estimate of the 95%
confidence interval for this year's S&P 500 return?
选项：
A.0.09934 to 0.12866 B.0.05025 to 0.17775 C.–0.33680 to 0.56480解释：
The reliability
factor for a 95% confidence interval with unknown population variance and
sample size greater than 30 is z.025= 1.96. The confidence interval estimate is:
这个sample size greater than 30 是迷惑信息？
