Is software different? CSE 403 � Submit a one sentence answer. Lecture 9 Risk assessment Risk Abstract view of risk � Exposure to the chance of injury or loss � Random variable � Outcomes with different probabilities � For a software project: � Failure to deliver on time � Exceeding resource limits � Not meeting quality threshold Concrete view of risks Risk analysis � Professors A, B, C, and D assign grades at � Types of Risk random according to known distributions. � Code Development Give your preference for the Profs (1 � External Dependency highest, 4 lowest) � Technology � Prof A. P(4.0) = ¾ , P(0.0) = ¼ � Personnel � Prof B. P(3.0) = ½ , P(2.0) = ½ � Requirements Change � Prof C. P(4.0) = ¼ , P(3.0) = ¼ , P(1.7) = ½ � Prof D. P(2.4) = 1 1
Sources of Risk I Sources of Risk II � Development risks � Integration risks � Code harder to develop than thought � Parts don't fit together � Learning curve on new facilities � Integration reveals bugs � Expected facilities not available � Integration reveals design errors � Need to iterate on requirements / design � Need to rewrite code after integration � Performance Issues � Code left out � Trigger other bugs Sources of Risk III Sources of Risk IV � Testing risks � Requirements Risks � Bugs will be found � New requirements introduced � Bugs won't be found � Change in Specification � Complexity of testing matrix � Inconsistencies in requirements � Deployment beyond development � User feedback machines � Market conditions � Difficulties in test automation and test tools � Platform and technology changes � UI and Workflow feedback Sources of Risk V Sources of Risk VI � Deployment Risks � People risks � Unexpected Loss of Personnel � Packaging distributable � Illness � Rights and licensing of components � Vacation � Legal signoff � Other demands on time � Marketing signoff � Group friction � Systems configuration � Inaccurate evaluation of skills � Drop in performance 2
Assess the five categories of risk for Gizmoball Quantification of Risk � Code Development � Modeling task completion as a random variable � External Dependency � Probability density � Technology � Distribution function � Personnel � Requirements Change Probability distributions on Sketch completion time graphs completion time for the following � Write the data entry � Write a tic-tac-toe program in Java Cumulative module Probability � Write a tic-tac-toe program in Visual � Hire a tester of Success Basic � Fix a simple bug 1.0 � Menu item not checked � Hire a contractor and have the when operation selected contractor write a tic-tac-toe program in � Fix a challenging bug Visual Basic � Intermittent problem with thread logic � Debug some else's tic-tac-toe program Time Completion graphs for TIC- What type of tasks might have TAC-TOE Programming the following DFs ? Cumulative Cumulative Probability Probability of Success of Success 1.0 1.0 Java Visual Basic Time Time Contractor Debug 3
Risk Analysis What to do with risk analysis � Avoid the risk � Identify top schedule risks to project � Transfer risk off the critical path � Risk exposure � Buy information � Size of Loss X Probability of Loss � Bring in outside help � (Better might be Expected loss) � Prototype � Publicize risk � Guess two numbers and multiply them � The sky is falling � Value in attempting to quantify � Schedule to accommodate some risk � Prioritize based upon exposure � Monitor risks as project progresses Give a strategy for passing the course from Prof A. You need 60 points to pass � � Two midterms and a final For each exam � P(0) = ¼ , P(20)= ½ , P(40) = � ¼ � There is an extra credit assignment worth 20 points � You may drop the class after the first midterm for free � Dropping the midterm after the second midterm is a W � You get kicked out of school if you fail a course twice, or withdraw 3 times When do you do the EC � assignment When do you drop the course? � 4
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