What-if Scenario (WISA)

A Project, by nature, is faced with a lot of uncertainty. Many times unanticipated changes happen which makes the project unstable. Proactive handling of uncertainty in Project Management brings about stability and smoothness in the handling of the project. This can be done by Scenario Analysis.

What If Scenario Analysis or WISA is a tool to anticipate contingent situations and be prepared to handle those situations. Usually, this is done at the scheduling stage of the project.

WISA (sometimes referred as deterministic simulation) used mainly in project analysis and schedule development. A schedule network analysis is performed using the schedule model to compute the different scenarios like delayed delivery of a major deliverable, impact of external factors such as a strike or change in the shipping procedures & processes, extending duration of certain specific activity under certain circumstances.

With different sets of activity assumptions, dozens of project schedule can be prepared through simulation. The most common simulation technique is Monte Carlo Analysis, in which a distribution of possible activity durations is defined for each schedule activity and used to calculate a distribution of possible outcomes for the total project. Early start/early finish, late start/late finish dates can be simulated. The following is an example:

First, A network diagram using PERT network is developed for an ideal situation. Then a scenario is developed like “What If Resource A is not available for three days starting from this date?” or “What If the working capital is not sanctioned as planned for this activity?”. Then the network diagram is altered to accommodate this situation to see how this impacts the project time lines and costs. If the time lines and budgets changed are acceptable, then the new PERT chart is put in place. Otherwise, alternate arrangement have to be made to see how things are going to work.

Today, tools such as Microsoft Project allow to do the WISA quickly and effectively. Hundreds of scenarios can be developed and applied so that their impact on project time lines and project cost can be estimated.

To simulate what-if scenario analysis, number of tools are available in Excel. Following are the few links to them:

• https://support.office.com/en-us/article/Introduction-to-What-If-Analysis-22bffa5f-e891-4acc-bf7a-e4645c446fb4
• http://www.gcflearnfree.org/excel2016/whatif-analysis/1/

https://www.quora.com/What-is-a-scenario-analysis-in-project-management

https://leadershipchamps.wordpress.com/2008/04/14/what-if-scenario-analysis/