b. if R? (Goodness of Fit Coefficient) is 0.98 in this estimated regression equation, what does that tell you? 8. How would extreme values affect volatility levels represented by the standard deviation statistic? 9. If both income and gender are considered as potential factors affecting spending behavior, write the two multiple linear regression equations for both female and male groups showing both gender and income are determinants of spending (Note: Think of dummy variables)