A Firm needs a rolling-horizon planning model for determining the optimal numbers of temporary personnel to hire to minimize cost over Months 3 thru 5 (though also, because of hiring arrangements, there are implied costs in Months 6 and 7, but these implied costs are treated as irrelevant to determining an optimal hiring plan).

There are two types of temps hired - 1-month ["1M"] and 3-month ["3M"].Those hired of either type require up-front training (at a cost to ABC of $500 per person); their monthly pay is as follows:

1M - $75003M - 6300

ABC has known staffing complements/commitments for the three types of personnel (long-term ["LT"], 1M, and 3M) - for 1Ms and 3Ms, for both a current month ["month 1"] and the following month ["month 2"], and for LTs, over an entire five month span - and needs to make optimal decisions for the 1M and 3M hires in Months 3, 4, and 5 to meet the known staffing requirements [stated in units of "staff-month"].

An illustration of the known staffing situation for a hypothetical month 1 is as follows:

Month:1 (This)2 (Next)345

LT63345

1M77# to hire?# to hire?# to hire?

3M 221+# to hire?# to hire?# to hire?

Known Staff-Month

Need:1512141512

(NOTE:All the specific values shown are part of the illustration.Actual month-to-month use of the model will involve entry of such values as ABC plan in "rolling time horizon" style.)

Unlimited numbers of 1M and 3M applicants exist; with respect to timing of hiring, there are limits on the number of hired 3Ms as follows:

Month:345

Limit:(no limit)32

Beyond Month 5 - i.e., for Months 6 & 7 - there need to be at least two 3Ms but not more than three.Costs in Months 6 & 7 are not considered relevant to the optimization.

To achieve a "smoother" pattern of required personnel, there is the possibility of shifting required staff-months of work between months 4 & 5.The limit in such shifting is that only up to four staff-months can be shifted either way.The cost of making shifts is as follows:

From Month 4 to Month 5:$3,000/staff-month

From Month 5 to Month 4:$5,000/staff-month

These costs, if incurred, are considered relevant to the optimization