23. Collinearity. Busy areas attract more fast food outlets. In densely populated areas, the number of competitors reduces sales.
Estimated Salary = b0 + 5 Age + 2 Test Score
The partial effect is relevant. It's worth it if you stay longer than 2.5 years since raising the test score by 5 points nets $10,000 annually.
The correlation of something with itself is 1.
Not without knowing the variance of x1 and y.
The partial and marginal slopes match because the two x− variables are uncorrelated.
29. The order of the variables in the correlation matrix is Z, X, T, Y (X, Z, T, Y is close).
City 1. Estimated revenues are: city 1: $312,000/month; city 2: $259,500/month.
The intercept, albeit ...