Use the data in LOANAPP.RAW for this exercise.
(i) How many observations have obrat > 40, that is, other debt obligations more than 40% of total income?
(ii) Reestimate the model in part (iii) of Computer Exercise C7.8, excluding observations with obrat > 40. What happens to the estimate and t statistic on white?
(iii) Does it appear that the estimate of (white is overly sensitive to the sample used?