why is residual model more dense are residuals in a model linear what does the model of cost distribution mean which p-spline is used to fit a marketing scheme? what is residuals what is the difference between the normal and the underlying residual in the model if the residuals are not linear, what model is being used to test for that are the residuals more dense what is the difference between the emp residual distribution and the theoretical normal? what model is the variable of marketing dummies what is the relationship between the dummy variable and the underlying normal distribution? what is the underlying normal for a residual in a generalized additive model why is dummy variable important in gam what is a dummy variable in gam why is dummy variable a problem in the model of marketing which is a characteristic of the GAM model that indicates that the marketing scheme did occur? what is the residual dummy spline what is the dummy variable in gam why is the dummy variable in the gam model more dense than the underlying normal? which variable indicates that a marketing scheme actually occurs?