Statistics for Business: Decision Making and Analysis, 3rd Edition

• ... confidence interval includes zero, the partial slope might be positive or might be negative. Just because we don’t know the direction (or sign) of the slope doesn’t mean it’s 0.

• Don’t think that the order of the explanatory variables in a regression matters. The partial slopes and t-statistics adjust for all of the other explanatory variables. The adjustments that produce the partial slopes are not performed sequentially.

23.1 Analytics in Excel: Subprime Mortgages

Read the file 22_4m_subprime.csv into Excel. The worksheet has 373 rows and five columns. The first column is the response, the annual percentage rate (APR). The next four columns are the loan-to-value ratio (LTV), credit score, stated income (in thousands of dollars, rounded), and the ...