Schedule Network Analysis

Schedule Network Analysis technique is used to develop schedule model. Under this we can use different technique like Critical Path, Critical Chain, resource optimization to calculate early start, early finish, late start and late finish activities.

Schedule Network Analysis is used under Develop Schedule process.

Reserve Analysis

During the estimation based on the uncertainties in the project one should park extra duration and or money which we call it as buffer. This is also called as reserves. There are two types of reserves: one is Contingency reserve and the second is Management reserve. Contingency reserve is based on “known unknown” and Management reserve is “unknown unknown”.

Contingency reserve can be derived based on quantitative risk analysis or based on standard deviation method or using organizational practices by putting some percentages.

Management reserve will be under management control and again this is derived based on unforeseen things which may happen to the project considering experience, historical data, contract terms and conditions, enterprise environmental factors, etc…

Reserve Analysis technique is used under the processes Estimate Activity Duration, Estimate Costs, Control Costs and Control Risks.

Three Point Estimating

To improve the estimation accuracy instead of considering only one value we can consider three values. This will cover most of the uncertainties. Three Point Estimating considers three values namely: Most likely or realistic value, Pessimistic or the worst value and Optimistic or the Best value. Depending on the distribution we use either of the below formula.

(P+4M+O)/6 which is Beta distribution or (P+M+O)/3 which is Triangular distribution.

Beta distribution is the weighted average which is also called as PERT (Program Evaluation and Review Technique).

Under the PERT one can derive the standard deviation and variance.Standard Deviation for an activity is (P-O)/6 and Variance is Standard deviation Square.

Three Point Estimating technique is used under the processes Estimate Activity Duration and Estimate Costs.

Parametric Estimating

Parametric Estimating is based on both historical data and the mathematical approach considering different variables. For example, 10 machines to be installed. To install one machine it takes one day. For 10 machines it may take approximately 10 days. One machine one day is the historical data and the calculation for 10 machines 10 days is mathematical model. So here we are considering both historical and mathematical approach unlike Analogous estimating where we consider only historical data. This technique provides higher level of accuracy.

Parametric Estimating technique is used under processes Estimate Activity Duration, Estimate Costs processes.

Analogous Estimating

Analogous Estimating technique is used for estimating duration, cost based on the previous similar projects data which is historical data. The word analogy means history. Even though this technique is less accurate, it is less time consuming and less costly.

Analogous Estimating technique is used under processes Estimate Activity Duration, Estimate Costs processes.

Bottom-Up Estimating

This estimation technique is used to aggregate the duration or cost from the lower level of the WBS structure. Individual activities aggregated to work packages. If it is difficult to estimate at activity level then further the activity is decomposed to more detail. And estimation is done at these detail level and aggregated to activity level.

Bottom-Up Estimating is the most accurate estimation technique but is time consuming.

Bottom-Up Estimating technique is used under the processes Estimate Activity Resources and Estimate Costs.

Published Estimating Data

This is the database maintained by organization about the unit price and production rates for resources which includes man, machine and material considering different geographical locations. Using this data one can estimate the budget and the resources required to execute the project. This database will be routinely updated by the organization.

For example, for a particular human resource with specific skill and experience what he/she may charge in a specific country?

Published estimating Data is the technique used under the process Estimate Activity Resources process.