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Instructor: Masoud Sadjadi http://www.cs.fiu.edu/~sadjadi/ sadjadi@cs.fiu.edu
CEN 4021 8 th Lecture
CEN 4021: Software Engineering II 9 th Lecture 2
Software Project Planning ( P OMA)
– Risk Analysis and Planning
CEN 4021: Software Engineering II 9 th Lecture
Risk Analysis and Planning
What is “risk”?
Definition:
Risk – A problem that has a greater than
0% but less than 100% probability of occurrence .
A problem is an event that has a negative value associated with it.
If the probability a risk has a 100% of occurring it is a problem.
Examples of risk include: losing a critical resource or using an unreliable new technology in a software project.
CEN 4021: Software Engineering II 9 th Lecture
Risk Analysis and Planning
Risk can be listed , categorized , and potentially managed .
The earlier risk are handled, the better the chance of project success.
CEN 4021: Software Engineering II 9 th Lecture
Overly optimistic assumptions about the availability of some technology
Misunderstanding of the real impact of some new methodology
Miscalculation of the robustness (e.g., extensibility) or constraints of software design
Misunderstanding of customer requirements
Uncontrolled continuous changes of customer requirements
Unrealistic promises to customers made by overzealous sales people or company execs.
CEN 4021: Software Engineering II 9 th Lecture
Inadequate due diligence while choosing external sourcing
Incompetence of key personnel
Miscalculation of teamwork and group effectiveness
Unrealistic expectations about the availability or productivity of special skilled human resources.
CEN 4021: Software Engineering II 9 th Lecture
Risk Identification
Steps in starting the risk list:
1.
List those characteristics of the product that may not be well defined.
2.
List all unresolved issues for the tasks that will be performed in conjunction with the software project. Start by asking whether any process is defined, documented , and practiced in the organization.
CEN 4021: Software Engineering II 9 th Lecture
Risk Identification
Steps in starting the risk list:
3.
Identify risks associated with management of resources .
For example, hardware and software systems required for the project, licenses needed etc. Tools may not be available when needed.
Human resources represent a especially important type of resource for software projects. Obtaining the needed skilled people in a timely manner is always a problem.
CEN 4021: Software Engineering II 9 th Lecture
Risk Identification
Planning categories to identify risk:
Deliverables and product specification
Tasks and initial schedule
Goals, metrics, and measurements
Human resources
Processes and methodologies
Tools and equipment
CEN 4021: Software Engineering II 9 th Lecture
Risk Prioritization
Definition: Risk prioritization - The activity of ordering risks based on some criterion or set of criteria.
Recovery cost – The cost in terms of effort or financial expense to solve a problem should a risk materialize.
The cost identified may not be exact but rather identified as merely high , medium , and low . The associated risk would have similar values.
CEN 4021: Software Engineering II 9 th Lecture
Risk Prioritization
Risk Item
Item 1
Item 2
Item 3
Item 4
Recovery Cost
High
Medium
High
Low
Risk Priority
High
Medium
High
Low
Table 5.1. Risk Prioritization by Recovery cost
To apply the notion of recovery cost as an abstract value, experience in the development process is required.
CEN 4021: Software Engineering II 9 th Lecture
Risk Prioritization
Prioritization by Risk Value:
The prioritization of risk can be more complex.
It makes sense to view risks with a low chance of occurring as requiring less attention.
We can define the risk value ( RV ) as follows:
RV(j) = P(j) X RC(j)
P(j)
– the probability of risk item j becoming a real problem
RC(j)
– is the recovery cost for the risk item j when it turns into a real problem.
CEN 4021: Software Engineering II 9 th Lecture
Risk Prioritization
Defn: Risk Value - A recovery cost that is influenced and modified by another criterion or set of criteria. The probability of the risk turning into a problem is such an influencing factor, and when such a factor is taken into account in modifying the recovery cost, the result is the risk value.
Table 5.2. Risk Prioritization by Risk Value
Risk Item Prob. Of Occurrence
Item 1
Item 2
Item 3
Item 4
Item 5 0.3
CEN 4021: Software Engineering II
0.4
0.7
0.3
0.6
Recovery Cost
$600
$400
$3000
$1200
$700
Risk Value (RV)
240
280
900
720
210
9 th Lecture
Is the formal process in which risk factors are systematically identified, assessed and mitigated.
Is about understanding the internal and external influences that can cause failure
– Internal risk – within the control of project manager
– External risk – outside the control the manager
CEN 4021: Software Engineering II 9 th Lecture
A subset of project management that includes the processes concerned with identifying , analyzing , and responding to project risk
The result of the initial risk analysis is a risk plan that should be reviewed regularly and adjusted accordingly
The purpose is to uncommon causes of project variation
CEN 4021: Software Engineering II 9 th Lecture
A good project manager is a good risk manager
Risk management continues throughout the software process until the product is delivered
Risk analysis and mitigation continue through the implementation stages of the software process.
CEN 4021: Software Engineering II 9 th Lecture
Risks are analyzed and prioritized on a weekly basis and the current “top-ten” risk list is presented at each weekly project status meeting .
Mitigation occurs through working the risks with the project team.
CEN 4021: Software Engineering II 9 th Lecture
Negative impact of risk can include
– Diminished quality of product
– Increased cost
– Delayed completion
– Project failure
CEN 4021: Software Engineering II 9 th Lecture
Handling risk is a key skill for software project managers because so much can go wrong
Software projects are thought to be more complex because the product is intangible
The determined risk profile will affect any scheduling estimates
CEN 4021: Software Engineering II 9 th Lecture
Project manager deal with 3 general categories of risks
– Known knowns : know to the project team, e.g., not having a funding source. Risk is noted and in project plan.
– Known unknowns : know to the project team but not know as a reality to the project. E.g., not having access to the enduser may lead to incorrect requirements. These are described in the plan, prioritized and updated on a weekly basis
CEN 4021: Software Engineering II 9 th Lecture
Project manager deal with 3 general categories of risks (continued)
– unknown unknowns : these are unknown to the project team as both a category of risk and as a reality to this project. E.g., when a specific technology is used because it is dictated by the terms of the contract. These can be addressed by setting a budget for contingencies. Also consider risk transfer, a.k.a insurance
CEN 4021: Software Engineering II 9 th Lecture
CEN 4021: Software Engineering II 9 th Lecture
Part of risk management is about risk quantification
Concepts of risk quantification:
– Risk Event (item): precise description of what might happen to the project
– Risk probability : the degree to which the risk event is likely to occur
– Amount at stake (recovery cost): the loss if the outcome is unsatisfactory
– Risk exposure (risk value): the overall liability (quantified) potential of the risk
CEN 4021: Software Engineering II 9 th Lecture
Risk management is made up of:
– Risk identification
Identify potential risk event (thru checklists, problem decomposition, experience, etc)
– Risk quantification
Qualitative analysis: non-measurable data e.g., morale
Quantitative analysis
– Response planning
Identify resource reserves , and how mitigation can occur
– Monitoring and control
Correction action plans and monitoring their implementation
CEN 4021: Software Engineering II 9 th Lecture
Take the WBS and look for precedence bottlenecks .
These will show up as tasks that require many other tasks to be completed before they can begin.
See all the dependencies to successful completion, parallel tasks, critical paths.
Schedule is made riskier due to increases in the project task degree of concurrency , number of critical path items , and estimation errors
CEN 4021: Software Engineering II 9 th Lecture
Risk Mitigation
Defn: Risk mitigation – An activity that may reduce minimize, or totally avoid a risk.
Risk item: not being able to complete a system integration task with a specific tool because only one person posses that special skill.
Alt. 1 – Hire an extra person with the needed skill as a backup helper
Alt. 2 – Provide extra incentives to persuade the current employer to stay
Alt. 3 – Use an alternative system integration method that does not require this specific tool
CEN 4021: Software Engineering II 9 th Lecture
Which mitigation alternative should be chosen when several choices are available?
Which criteria should be used in decision making?
One of any several parameters as the basis for decision making including the ease of mitigation, probability of success of mitigation, and the cost of mitigation.
CEN 4021: Software Engineering II 9 th Lecture
Mitigation alternative Cost of mitigation
Alternative 1 $65,000
Alternative 2
Alternative 3
$50,000
$120,000
Table 5.3: Estimated Mitigation Costs for Risk Item J
CEN 4021: Software Engineering II 9 th Lecture
The mitigation cost value is defined as follows:
MVC(k) = P(k) X MC(k)
MVC(K) – mitigation cost value of alternative k
P(k) – probability of failure for alternative k
MC(k) – raw cost of mitigation for alternative k
See Table 5.4 in the next slide.
Mitigation value cost
– the cost of risk mitigation after taking into account another criterion or a set of criteria, such as probability of mitigation success
CEN 4021: Software Engineering II 9 th Lecture
Risk Mitigation
Mitigation alternative
Alternative 1
Alternative 2
Alternative 3
Table 5.4 Mitigation Value Cost
Raw risk mitigation cost
$65,000
$50,000
$120,000
Probability of failure
0.1
0.6
0.05
Mitigation value cost
$6500
$30,000
$6000
CEN 4021: Software Engineering II 9 th Lecture
Risk Mitigation
Mitigation Value Cost
Note that if P(k) is changed from the probability of failure to the probability of success , then the highest mitigation value cost would be the proper choice.
Sometimes the project manager faces the prospect of planning with a fixed budget for risk mitigation.
Therefore the risk items must be ranked.
See Table 5.5 in textbook.
CEN 4021: Software Engineering II 9 th Lecture
Prioritized risk item
Item 1
Item 3
Item 3
Expected removal date
06/30/2006
07/15/2006
01/30/2007
Removal dependency
Risk mitigation completed
Task 3 completed on schedule
Task 8 target met and risk mitigation completed
CEN 4021: Software Engineering II 9 th Lecture