- Problem Definition
On my previous blog posting, an analysis on schedule estimation was carried out. The Three point Estimation was carried out to compare the outcome with the project duration of 11 months set by the client.
For this blog posting an additional analysis was carried out using @RISK Simulation Software and a comparison between the two will be conducted and analysed.
- Feasible Alternatives
In this analysis we will be looking at a comparison between two different results achieved through different methodologies for the three point estimation.
- Using manual calculation as done in W2 Blog
- Using @RISK Simulation Software
- Develop the outcomes for each alternative
Because we are looking at a comparison of two results the two different outcomes are as follows.
- Matching results confirming the manual calculations
- Different results invalidating results from manual calculations
- Acceptable Criteria
For comparison purposes the acceptable criteria for this analysis will be similar to that of the W2 blog posting which was set as a duration estimate accuracy >90% .
- Analysis and comparison of the alternatives
Using the same set of data used in my W2 Blog Post we achieved the following results:
Comparison between alternatives:
|Time ( Months)||Manual||@RISK|
- Select the preferred alternative
Based on analysis result, we can see that the results obtained by the simulation software are slightly larger for the P80 and P90 but still are very similar confirming the results obtained in W2 Blog were correctly estimated. Although the software results must be considered as more accurate.
- Performance Monitoring & Post Evaluation of Result
Additionally the simulation gives us additional data that could also be used. The @RISK PERT Simulation also shows that we have a 95% chance of completing the project in 13.2 months where as we only have a 10% chance of completing the project within the project duration set by the client of 11 months.
Similar recommendation as W2 Blog post is advised here, the schedule to be analyzed a number of times as time goes by and as more information is available to get more accurate results.
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