
note: YEAR_DUM1 omitted because of collinearity
note: YEAR_DUM2 omitted because of collinearity
note: YEAR_DUM3 omitted because of collinearity
note: YEAR_DUM4 omitted because of collinearity
note: YEAR_DUM12 omitted because of collinearity
note: YEAR_DUM20 omitted because of collinearity
note: YEAR_DUM21 omitted because of collinearity
note: YEAR_DUM22 omitted because of collinearity
出现这种情况是为什么呢?对regression的结果有什么影响呢?year dummy会对变量的显著性产生影响,什么时候加?什么时候不加呢?菜鸟一枚~~~~求助于大神ing