1. Mrs. Smith and her husband, George, are planning their retirement and their dream house on the lake. The lot for the house sits high on a bluff with a beautiful view of the Chesapeake Bay. The plans for the house show the size of the house to be 3,900 square feet. The average price for a lot and house similar to this one has been $175 per square foot. Fortunately, George is retiring from 20 years as an electrician and feels he can save money by installing the electric himself. Mrs. Smith feels she can take care of the interior decorating.
The following average cost information is available from a local bank that makes loans to local contractors and disperses progress payments to contractors when specific tasks are verified as complete.
24 % |
Excavation and framing complete |
8 % |
Roof and fireplace complete |
3 % |
Wiring roughed in |
6 % |
Plumbing roughed in |
5 % |
Siding on |
17 % |
Windows, insulation, walks, plaster, and garage complete |
9 % |
Furnace installed |
4 % |
Plumbing fixtures installed |
10 % |
Exterior paint and finish hardware installed |
6 % |
Carpet and trim installed |
4 % |
Interior decorating |
4 % |
Floors laid and finished |
a.  What is the estimated cost for the Smith’s house if they use contractors to complete all of the house?
b.  Estimate what the cost of the house would be if the Smith’s use their talents to do some of the work themselves.
2. System Project. Using the “complexity weighting†scheme shown in Table 1 and the function point complexity weighted table (Table 2) shown below, estimate the total function point count. Assume historical data suggest five function points equal on person month and six people can work on the project.
Complexity Weight Table |
||
Number of inputs | 20 | Rated complexity average |
Number of outputs | 10 | Rated complexity low |
Number of inquiries | 10 | Rated complexity low |
Number of files | 40 | Rated complexity high |
Number of interfaces | 30 | Rated complexity high |
Table 1 – Complexity Weighting Table
The total function point count is:
Complexity Weighting |
||||||
Element |
Count |
Low |
Average |
High |
 |
Total |
Inputs |
20 |
 |
20 x 4 |
|
= |
80 |
Outputs |
10 |
20 x 2 |
 |
|
= |
40 |
Inquiries |
10 |
10 x 2 |
 |
|
= |
20 |
Files |
40 |
|
 |
40 x 12 |
= |
        480 |
Interfaces |
30 |
|
|
30 x 15 |
= |
450 |
|
|
|
TOTAL |
= |
1,070 |
Table 2 – Function Point Complexity
a. What is the estimated project duration?
b. If 20 people are available for the project, what is the estimated project duration?
c. If the project must be complete in six months, how many people will be needed for the project?
3. Below is a project WBS with cost apportio
ned by percents. If the total project cost is estimated to be $500,000, what are the estimated costs for the following deliverables?
a. Systems Design?
b. Programming?
c. System testing?
d. What weaknesses are inherent in this estimating approach?