NO.PZ201512020300000701
问题如下：
With respect to forecasting annual gross revenue, Maxwell’s best course of action to deal with the inputs problem should be to:
选项：
A. simulate the ECI and the CSI independently
B. build the correlation explicitly into the simulation.
C. estimate revenues using the ECI only and eliminate the CSI from the simulation.
解释：
B is correct. Both the nightly room rate and the occupancy rate are dependent on inputs, ECI and CSI, which are correlated. If there are correlated inputs, there are two solutions to this problem. One is to allow only one of the two inputs to vary, emphasizing the one with the larger impact. The second solution is to the build the correlation explicitly into the simulation. Simulating ECI and CSI independently is not a remedy for the correlated inputs problem. Further, the relation between CSI and the occupancy rate is stronger than that between ECI and nightly room rates, which suggests that CSI should be kept if one of the two inputs is to be removed from the simulation.
A is incorrect because the two input variables, ECI and CSI, are correlated, and simulating them independently is not appropriate. The remedies include dropping one of the probabilistic inputs or building the correlation into the simulation explicitly.
C is incorrect because the relation between CSI and the occupancy rate is stronger than that between ECI and nightly room rates, which suggests that CSI should be kept if one of the two inputs is to be removed from the simulation.
