问题如下：
If given the multiple R-squared is 0.81, which one of the following explanations is least likely correct?
选项：
A.The model, as a whole, could explain 81% of dependent variable’s change.
B.The correlation’s square between predicted and actual values of the dependent variable is 0.81.
C.Some of the independent variables could explain 81% of dependent variable’s change.
解释：
C is correct.
考点: R-squared and adjusted R-squared.
解析: Multiple R-squared代表的是多元回归下的，代表的是整个模型作为一个整体对因变量的解释力度，所以A正确，C错误。在多元回归模型下， 等于估计的因变量与因变量之间的相关系数的平方，所以B选项也是正确的。
adjusted R^2 = (R estimated y and y )^2 B 选项中为什么不是0.9? 是(R estimated y and y )^2 表示correlation 还是就R estimated y and y 表示correlation ？ 谢谢。
