Quantitative Risk Analysis
4. Quantitative Risk Analysis Quantitative risk analysis analyzes numerically the effect aproject risk has on a project objective.The process generally follows qualitative analysis and utilizestechniques such as Monte Carlo simulation and decision analysisto: Determine the probability of achieving a specific project objective. Identify risks requiring the most attention by quantifying theirrelative contribution to project risk. Identify realistic and achievable cost, schedule or scope targets. Quantify project outcomes and their probabilities. Guides project management decisions under conditions ofuncertainty such as determination of size of contingency.
4.1 Inputs to Quantitative Risk Analysis Organizational & Environmental Process AssetsInformation from past projects, studies of similar projects, riskdatabases. Project Scope StatementRisk Management PlanMajor elements from the plan needed include roles &responsibilities, budgets and schedule for risk managementactivities, risk categories, definitions of probability & impact, and thestakeholders’ tolerances. Risk RegisterList of risks, relative ranking of risks, and risks grouped by category. Project Management Plan Project Schedule PlanProject Cost Plan
4.2 Tools and Techniques for Quantitative Risk Analysis1. Data Gathering & Representation Techniques. Interviewing: Interviewing techniques are used to quantify theprobability and impact of risks on project objectives. Informationneeded depends on the type of probability distributions that will beused (Need distribution parameters). For example, if triangular distributions are used,information would be gathered on the optimistic,pessimistic, and the most likely scenarios. If normaldistribution is used information on the mean & standarddeviation would be needed,Documenting the rationale of the risk ranges is animportant component of the risk interview because itindicates reliability of data.Expert Judgment: Subject matter experts are useful to validatedata. They can come from the organization or from outside.
3-point Estimates for use in triangular distribution
4.2 Tools and Techniques for Quantitative Risk Analysis2. Quantitative Risk Analysis & Modeling Techniques Sensitivity analysis. Used to determine which risks have the most potentialimpact on the project. Sensitivity analysis examines the extent to whichvariation of a project element affects a project objectivewhen all other uncertain elements are held at theirbaseline values. Expected monetary value analysis. The method considers the probability of each possibleoutcome and determines the average value of alloutcomes
4.2 Tools and Techniques for Quantitative Risk Analysis Decision tree analysis A decision analysis can be structured as a decision tree.The decision tree is a diagram that describes a decisionunder consideration and the implications of choosingone or another of the available alternatives.It incorporates probabilities of risks and the costs orrewards of each logical path of events and futuredecisions.Solving the decision tree gives the expected value ofeach decision. The decision-maker can select thedecision yielding the highest expected value when allthe uncertain implications, costs, rewards andsubsequent decisions are quantified.
4.2 Tools and Techniques for Quantitative Risk Analysis Simulation. A project simulation uses a model that translates theuncertainties specified at a detailed level into theirpotential impact on objectives at the level of the totalproject.Project simulations are typically performed using theMonte Carlo technique.For a cost risk analysis, a simulation may use thetraditional project WBS as its model. For a schedule riskanalysis, the Critical Path Method (CPM) schedule isused.
4.3 Outputs from Quantitative Risk Analysis1. Risk Register UpdatesRisk register is updated to reflect results from thequantitative risk analysis. Information added include: Probabilistic analysis of the project. Forecasts of potential project schedule andcost results listing the possible completiondates or project duration and costs with theirassociated confidence levels (usually as acumulative distribution see Figure 11-13.)Analysis results are used in conjunction withthe stakeholders’ tolerances to estimate costand time contingencies.
4.3 Outputs from Quantitative Risk Analysis Probability of achieving the project cost and time objectives.The probability of achieving the project objectives under thecurrent plan can be estimated using quantitative risk analysisresults. In Figure 11-13, probability of project cost being within41 is about 12%.Prioritized list of quantified risks.This list of risks includes those posing the greatest threat orpresenting the greatest opportunity to the project togetherwith a measure of their impacts.Trends in quantitative risk analysis results.As the analysis is repeated, a trend of results may becomeapparent. Trends may be useful for developing risk responses.
4. Quantitative Risk Analysis Quantitative risk analysis analyzes numerically the effect a project risk has on a project objective. The process generally follows qualitative analysis and utilizes techniques such as Monte Carlo simulation and decision analysis to: Determine the probability of achieving a specific project objective. Identify risks requiring the most attention by quantifying their