这题为什么不是拒绝原假设但接受claim

11题跟第6题一样 题目问的不是reject or accept his claim 吗？不应该是reject the null and accept his claim 吗？求解答，很费解

第6题 这一题不应该是reject the null but accept his claim 吗？还是我理解错了？

这一题不应该是reject the null but accept his claim 吗？还是我理解错了？

An investment manager is given the task of beating a benchmark. Hence the risk should be measured A In terms of loss relative to the initial investment B In terms of loss relative to the expected portfolio value C In terms of loss relative to the benchmark D In terms of loss attributed to the benchmark 老师您好！能举个例子说明一下D选项为什么是绝对衡量指标吗？

这道题中说the probability of observing such a large alpha by chance is only 1％，是不是理解成投资者认为极大的超额收益偶然出现的概率只有1%？如果是这样，原假设是不是应该是alpha≠0？

A portfolio manager produced an alpha of 2.5% based on monthly returns over a 6 year period. Under the assumption of a normal distribution, the portfolio manager claims that the probability of observing such a large alpha by chance is only 1%. To test her claim, one would use a t-test using which level of confidence? 老师您好！我想问一下，就是这道题里他说观测到很大的α，是指单尾的1%还是双尾的1%。我认为是单尾的，所以在进行假设检验找临界值的时候，应该找98%的两个临界值。这样两边各留出1%，才能判断原假设：“α=0”是否是正确的。

John, a portfolio manager, claims to have consistently produced excessive returns (over and above the benchmark returns) 97.5% of the time due to her skill and not luck. To support her claim, she presents regression results based on 60 monthly observations as follows: alpha = 0.43%, standard error of alpha = 0.21% Would you reject the null hypothesis of true α = 0 and accept her claim of superior... 老师您好！我想问一下，这道题到底置信区间是多少？他说97.5%的概率下，他的优异表现是源自于能力不是运气。我的理解是，他的表现好，那么应该是单尾的97.5%，而右侧的尾巴是2.5%，而不看亏损的一侧。做假设检验时，95%的置信区间恰好表示了左右两边各2.5%的情况，因此，置信区间应该是-1.96到1.96。

这一题答案是不是错的？视频讲解的公式列出来没问题，但最后解析里的数据应该是14.3%而不是13.4%

C怎么错le