frm part I notes
book2 page185

书中讲到Examples of Misspecification of functional form：
举例：
The correct specification of the model is as follows:
R=b0+b2*B+b2*lnM+b3*lnPB+b4*FF+residual

Misspecification #1. Omitting a Variable
Suppose we do not include lnM in the regression model:
R=a0+a1*B+a2*lnPB+a3*FF+residual
If lnM is correlated with any of the remaining independent variables(B,lnPB, or FF), then the error term is also correlated with the same independent variables and the resulting regression coefficients (the estimates of a0, a1, a2) are biased and inconsistent. That means our hypothesis tests and predictions using the model are unreliable.

我的问题是：
忽视重要变量导致模型很多问题这没错。但是如果这个变量和其它变量相关，这不就是多重共线性了吗，难道不就应该忽略掉吗？