关于多重线性和自相关,有一道题答案中解释:Multicollinearity can bias the coefficients because the shared movement of the independent variables. Serial correlation biases the standard errors of the slope coefficients. 关于后半句我理解得不清楚。请问the standard errors of the slope coefficients的公式是怎样的?slope coefficients我理解是个确定的值,怎么还有标准差?是利用哪些信息数据怎么计算出来?而自相关怎么影响到它的?