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17th May 2012 |Neil Dunkerley | 2
About EC Harris
■ EC Harris is a leading global Built Asset Consultancy, helping clients makethe most from their investment and expenditure in built assets.
■ We work across a wide range of sectors, and our professional skills includedisciplines from asset and facilities strategy to management informationsystems – quantity surveying, programme, project, risk and constructionmanagement to software development.
■ In 2011 we became part of the ARCADIS Group of companies
■ ARCADIS is an international company providing consultancy, design,engineering and management services in infrastructure, water, environmentand buildings.
17th May 2012 |Neil Dunkerley | 3
Project Risk Analysis
■ Quantitative Risk Analysis (QRA)
– Why
– Modelling
– Outputs
– Benefits
■ Range Modelling
■ Railway Possessions
■ Wave AnalysisNationwide
07/Jan/01
04/Feb/01
04/Mar/01
01/Apr/01
29/Apr/01
27/May/01
24/Jun/01
22/Jul/01
19/Aug/01
0% 4% 7% 11%
15%
18%
22%
2 6%
29%
3 3%
37%
40%
44%
48%
51%
55%
59%
62%
66%
70%
73%
77%
81%
84%
88%
92%
95%
99%
Co
mp
leti
on
Dat
eR
ang
e
Sorted by 75% completion date
Distribution for Risk total / Risktotal/CK109
Va
lue
sin
10
^-4
Values in Thousands
0123456789
Mean=1053.606
0 1 2 30 1 2 3
5% 90% 5%.4126 1.7341
Mean=1053.606
17th May 2012 |Neil Dunkerley | 4
Project Risk Analysis
■ To enable Clients to gain confidence in estimates andschedules
– should understand the outputs
– appropriate analysis should be undertaken
■ Aids decision making
17th May 2012 |Neil Dunkerley | 5
QRA – Why? Overspend & Overrun
■ Cost
– Deterministic estimation
– Unforeseen events e.g. risks
– Scope uncertainty / change
– Assumptions incorrect
– Exclusions
■ Schedule
– Deterministic estimation
– Unforeseen events e.g. risks
– Scope uncertainty / change
– Assumptions incorrect
– Exclusions
– Sunny-day forecasting
– Human factors (sickness,holidays, etc)
– Key milestone constraints
– Perceived critical path
17th May 2012 |Neil Dunkerley | 6
QRA – Modelling■ Cost
– Review / check estimate
• Scope
• Inflation – base date
• Contingency
• Assumptions / Exclusions
– Modelling
• @Risk
• Uncertainty in quantities & rates
• Risks e.g. ground conditions, approvals, exchange rates,political, etc
Distribution for Risk total / Risktotal/CK109
Va
lue
sin
10
^-4
Values in Thousands
0123456789
Mean=1053.606
0 1 2 30 1 2 3
5% 90% 5%.4126 1.7341
Mean=1053.606
Distribution for Risk total / Risktotal/CK109
Values in Thousands
0.000
0.200
0.400
0.600
0.800
1.000Mean=1053.606
0 1 2 30 1 2 3
5% 90% 5%.4126 1.7341
Mean=1053.606
17th May 2012 |Neil Dunkerley | 7
QRA – Modelling■ Schedule
– Review / check schedule
• Scope
• Contingency / Float
• Assumptions / Exclusions
• Logic – Constraints, Missing, Leads & Lags, Types
• Calendars
• Resources (Levelling, Productivity)
– Modelling
• Pertmaster
• Correct logic errors / remove constraints
• Uncertainty in task duration (generic, task / group specific)
• Risks e.g. ground conditions, approvals, weather, political, etc
17th May 2012 |Neil Dunkerley | 8
QRA – Outputs
■ Cost
– Total
– Sections / Elements
– Contingency
– Target costs
– Uncertainty / risk sensitivity
■ Schedule
– Schedule Finish Dates
– Task Start / Finish Dates
– Sectional completions
– Key milestones
– Float / Contingency
– Task Criticality
– Duration / Schedule Sensitivity
– Uncertainty / risk sensitivity
17th May 2012 |Neil Dunkerley | 9
QRA – Benefits?– Independent review of estimate / schedule
– Scope defined (baseline)
– Assumptions & Exclusions defined & agreed
– Unforeseen events (e.g. risks) identified & prioritised formanagement (i.e. risk register)
– Contingency estimated & agreed
– Schedule
• Model key tasks / stage durations & anticipated finish
• Critical path review and task criticality
• Removes double counting of project delay in cost risk register
17th May 2012 |Neil Dunkerley | 11
Range Modelling – Why?■ Organisations are careful when publishing estimates as failing to reliably
predict the outturn cost can result in a loss of reputation
■ Often the world is not that simple, programmes and projects change
■ A more informative method of presenting estimates, is to present anexpected outturn and express the range of likely outcomes that the outturncost is likely to fall within. This has two advantages:
– Early estimates reflect the range of costs associated with solutions indevelopment
– Estimates for projects nearing construction should be become morecertain
17th May 2012 |Neil Dunkerley | 12
What EC Harris has delivered
■ The Highways Agency post the Nicholls Review 2006 selected EC Harris tosupport range estimating given our industry experience and our flexibility tomobilise to meet demanding timescales.
■ Created a Range Modelling Tool
– that captures estimates based upon a standard WBS; with estimates,risk and uncertainty allowances.
■ Particular innovations of the Range Modelling Tool are:
– Takes into account different modelling distributions, accuracy of data,and dependencies
– Automate the process of uploading project estimates from separateexcel files.
– In built checking mechanisms in triplicate, confirms the accuracy ofresults.
17th May 2012 |Neil Dunkerley | 15
Railway Projects
Development /Preparatory Works
EngineeringWorks –
Possession/s
17th May 2012 |Neil Dunkerley | 16
Railway Possessions
WorksTakePoss.
ReturnPoss.
Prep.Works
Reinstatement.Works
OperationalRailway
OperationalRailway
Milestone/s Milestone
17th May 2012 |Neil Dunkerley | 18
Wave Analysis
■ A Wave model and chart are a form of time risk modelthat shows the range of completion dates for each ofmany small projects, usually of a similar nature
Nationwide
07/Jan/01
04/Feb/01
04/Mar/01
01/Apr/01
29/Apr/01
27/May/01
24/Jun/01
22/Jul/01
19/Aug/01
0% 4% 7% 11%
15%
18%
22%
26%
29%
33%
37%
40%
44%
48%
51%
55%
59%
62%
66%
70%
73%
77%
81%
84%
88%
92%
95%
99%
Co
mp
leti
on
Dat
eR
ang
e
Sorted by 75% completion date
17th May 2012 |Neil Dunkerley | 19
Wave Analysis■ Each project will have a planned completion date
■ The effect of any opportunities or risks to completion is to spread theplanned completion date over a range:
p la n n e dc o m p le t io nd a te
5 M a r , 2 0 0 1 3 1 M a r , 2 0 0 1
e a r ly c o m p le t io n la te c o m p le t io n
t im e lin e
■ Each date within this rangehas a probability ofoccurrence
■ There is a date in the rangeat which there is a 75%chance the project will becompleted on or before
plannedcom pletiondate
5 M ar, 2001 31 M ar, 2001
early c om pletion late com pletion
P robab ility
5% probability c om pletionon or before
95% probability c om pletionon or before
Probability
75% probability
17th May 2012 |Neil Dunkerley | 20
Wave Analysis
■ This is one project of many.
07/Jan/01
04/Feb/01
04/Mar/01
01/Apr/01
29/Apr/01
27/May/01
24/Jun/01
22/Jul/01
19/Aug/01
0% 3% 7% 10%
13%
17%
20%
23%
27%
30%
33%
37%
40%
43%
46%
50%
53%
56%
60%
63%
66%
70%
73%
76%
80%
83%
86%
89%
93%
96%
99%
Co
mp
leti
on
Dat
eR
ang
e
17th May 2012 |Neil Dunkerley | 21
Nationwide
07/Jan/01
04/Feb/01
04/Mar/01
01/Apr/01
29/Apr/01
27/May/01
24/Jun/01
22/Jul/01
19/Aug/01
0% 4% 7% 11%
15%
18%
22%
26%
29%
33%
37%
40%
44%
48%
51%
55%
59%
62%
66%
70%
73%
77%
81%
84%
88%
92%
95%
99%
Co
mp
leti
on
Dat
eR
ang
e
Sorted by 75% completion date
Wave Analysis
■ The ranges for all the other projects are also plotted.
■ The red line is the desired finish date for all of the projects.
17th May 2012 |Neil Dunkerley | 22
Project Risk Analysis
■ Clients should understand the outputs
■ Appropriate analysis should be undertaken
– based upon the available information and within theavailable time
– get out what you put in!
■ Enable Clients to gain confidence in cost estimates andprogrammes
■ Better decision making
■ Successful projects – delivered on time and withinbudget