Crystal Ball Analysis - Construction Time

A prestigious university in the Pacific Northwest is planning to build a new business school building on campus. To accomplish this, the activities listed in the following table must be completed. For most of these activities there is a set of predecessor activities that must be completed before the activity begins. For example, the foundation cannot be laid until the building is designed and the site prepared. Activity Predecessors A. Obtain Funding - B. Design Building A C. Prepare Site A D. Lay Foundation B, C E. Erect Walls and Roof D F. Finish Exterior E G. Finish Interior E H. Landscape Grounds F,G Obtaining funding will likely take somewhere around 9 months. They estimate about a two-thirds chance that the time required to obtain funding will be within two months (plus or minus) of this estimate, but there is a small chance this estimate could be significantly off. The architect has estimated the time required to design the building is equally likely to be anywhere between 5 and 9 months. The general contractor has provided three estimates for each of the construction tasks—an optimistic scenario (minimum time required if the weather is good and all goes well), a most likely scenario, and a pessimistic scenario (maximum time required, e.g., if there are weather or other problems). These estimates are provided in the table below. Finally, the landscaper has guaranteed that his work will be completed in 1 month. Activity Optimistic Most Likely Pessimistic C. Prepare Site 5 8 10 D. Lay Foundation 3 3.5 4 E. Erect Walls and Roof 6 9 11 F. Finish Exterior 5 7 10 G. Finish Interior 6 7 10 Use Crystal Ball to run a simulation of this project. Please use the following Run Preferences: 2000 Trials, Use Same Sequence of Random Numbers with an Initial Seed Value of 999, and the Latin Hypercube Sampling Method with a Sample Size of 500. Use the Set Cell Value to Distribution Mean option under Cell Preferences. Also, be sure to clearly indicate which cells are assumption cells and which are forecast cells, and indicate directly on the spreadsheet the distributions and parameters used for each assumption cell. Be sure to work directly in the provided Excel file. Do not work in a separate spreadsheet and copy your models into this file—Crystal Ball data do not come through with Excel’s copy and paste. Answer each of the following questions in a sentence or two. Paste in any Crystal Ball output required for your analysis. (Use Copy Chart under the Edit menu of the forecast chart window.) a. What is the expected time (mean) for project completion? b. They hope to have the building ready for classes in 40 months. What is the probability that the project will be completed in 40 months or less? c. Which of the activities would be most important to keep an eye on in order to complete this project on schedule? Explain.