1. A regression can suffer from several different violations of the classical assumptions. Among these are:

Heteroskedasticity Omitted Variables Serial Correlation

Multicollinearity Endogeneity

For each of the items presented below, tell me which of these violations it addresses and, based on what you see, is this likely a problem or not.Convince me that you know what's going on with each of these. I need to know that you know, if you know what I mean.

A. A VIF of 8.231.

B. A high R², but no significant estimated coefficients.

C. A scatterplot that looks something like this:

Scatterplot of X1 and X2 6 0 0.2 0.4 0.6 0.8 1.2Resid N 1.5 0.5 -0.5 -1 -1.5 -2 E. A residual plot that looks something like this: 4e+06 Revenue 1e+06 2e+06 3e+06 De+00 800 1000 200 400 600 Screens