老師好，能再解答下押題卷51題嗎，沒有聽懂。
請(qǐng)問押題39題中，F(xiàn)檢驗(yàn)自由度為什么選2?
上面那個(gè)cov的題目為什么EA是10%，老師可不可以算一下？
下列哪項(xiàng)是正態(tài)分布的特征？lV：continuous和unbounded。這里的unbounded應(yīng)該是無限的意思吧？但是normal的值域應(yīng)該是有限的？這里說無限是不是不太準(zhǔn)確
這總結(jié)一下唄
為了檢驗(yàn)single partial slope coefficient in a multiple regression with 3 independent variables, we use a critical t with degrees of freedom equal to the sample size minus four(n-4)這個(gè)怎么理解？
書上只說了ABC三個(gè)選項(xiàng)吧？第四個(gè)是不是表示的是bootstrapping?
這個(gè)41題，題干似乎沒有給原假設(shè)是什么，單單得出這個(gè)統(tǒng)計(jì)量大于79.8可以確定他大于14%嗎？怎么判斷的
statistically significant的意思是unlikely to have occurred merely by chance應(yīng)該怎么理解？
老師，r2等于相關(guān)系數(shù)的平方嗎
老師，請(qǐng)問這個(gè)63題的C和D選項(xiàng)，differences between the actual and estimated squared S&P 500 return和the sum of squared differences between the actual and estimated stock return，不太明白怎么區(qū)分
這里兩個(gè)題思路一樣，把VAR（。。）展開后，并不知道A和B的方差誒，應(yīng)該怎么求解
這題是怎么做出來的 In a metal fabrication process, metal rods are produced that have an average length of 20.5 metres with a standard deviation of 2.3 metres. A quality control specialist collects a random sample of 30 rods and measures their lengths. 問題Suppose the resulting sample mean is 19.5 metres. Do you think that this sample result is unusually small? Explain. 答案：We have a random sample of metal rods drawn from a much larger population. A sample mean of only 19.5 metres is about 2.38 standard deviations below what we expect. The sample mean of 19.5 metres is unusually small.
為什么e u不是正相關(guān)？
為什么不可以用ex2—（ex）2？我算出來這樣子結(jié)果不對(duì)
程寶問答
金程問答