事后预测
参考答案：
解析：事后预测是指在预测期内，模型中自变量和因变量都是已知的。
改错，下列各句均有两个错误，请指出并改正。
1. Danny is skateing for wards.
2. There is four season in a year.
3. Sometimes Danny learn to make snow balls.
4. Are winter your favourite seasons?
5. Danny walk to park yesterday.
以下结论正确的为（）。
A.A
B.B
C.C
D.D
