The approach outlined in Section XXXXXXXXXXdoes not readily account for correlations in facility failures. One way to do so is to define failure scenarios. Snyder et al XXXXXXXXXXformulate the...

The approach outlined in Section 8.10.1 does not readily account for correlations in facility failures. One way to do so is to define failure scenarios. Snyder et al. (2006) formulate the following model in which they define a priori a number of scenarios, each representing different combinations of facility failures. Let S be the set of scenarios and for each scenario s
 S, let qs be the probability that scenarios s
 S occurs. We also define the following additional input

Also let b_j
be the capacity, measured in terms of the total demand, that can be assigned to a facility at candidate site j
 J. Finally, define the following decision variable:

With this notation, we can formulate a scenario-based planning model as follows:

(a) Clearly state what the objective function and each of the constraints does in words.

(b) Normally, scenarios are used to define different future conditions that the current input values (such as the demands or travel costs) might take on under different future conditions. How do the scenarios in the model outlined above differ from this more usual approach?

(c) Would you use this model as defined above? Justify your answer.