Page 187 - BA2 Integrated Workbook - Student 2017
P. 187

Risk 2: probability




               Example:

               ABC is a furniture retailer. It offers a customer loan facility. If a new customer
               requests a loan then ABC either refuses it, gives a high loan limit, or gives a low loan
               limit. From a number of years past experience the probability that a new customer
               makes a full repayment of a loan is known to be 0.95, whilst the probability of non-
               repayment is 0.05 (these probabilities being independent of the size of loan limit).
               The average profit on the loans, per customer is given by the following table.


                                             Loan limit – High     Loan limit – low
               Full repayment                       $50                   $20
               Non-repayment                     ($200)                  ($30)

               A decision tree representing this information is shown below.

                                                        Repay 0.95
                                                                          $50
                                       A


                          High                          Not repay 0.05
                          loan                                             ($200)

                    C
                                     Refuse

                                                        Repay 0.95
                                                                           $20
                           Low          B
                           loan
                                                       Not repay 0.05
                                                                           ($30)

               From this the expected value can be calculated at the outcome points A and B:

               Expected Value at point A: (0.95 × 50) + (0.05 × (200)) = 37.5

               Expected value at point B: (0.95 × 20) + (0.05 × (30)) = 17.5

               At decision point C compare the EVs of $37.5 and $17.5.


               Recommendation: if a customer requests a loan give him/her a high loan limit.





               Try TYU 8









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