estimation - the next level - and beyond

EstimationThe Next Level

Ton DekkersIWSM – Ankara – October 25th 2013

NEtherlands Software Metrics users Association

Ton Dekkers - RolesNetherlands Software Metrics Association (NESMA)

President

International Software Benchmarking Standards Group (ISBSG)Past President

Common Software Measurement International Consortium (COSMIC)International Advisory Committee

Dutch Association of Cost Engineers (DACE)WG Parametric Estimation

Southgate Pedestrian Bridge, Melbourne

Estimation conceptsMost common

techniquesExtrapolation from ActualsExpert Opinion

Cost Estimating

The process of collecting and analyzing historical data and applying quantitative models, techniques, tools, and databases to predict the future cost of an item, product, program, or task

Purpose of cost estimating:Translate system/functional requirements associated with

programs, projects, proposals, or processes into budget requirements

Determine and communicate a realistic view of the likely cost (effort, schedule) outcome, which can form the basis of the plan for executing the work

A Bridge to the Future

EstimateHistorical data Time

nowSource: ICEAA training

Cost Estimation TechniquesAnalogy

Build-Up

Parametric

Parametric Estimating - ProcessCollect Data

Relevant, Reliable

Normalise DataCost level, activity level

Determine correlationsValidate correlations

R2 > 0.8 is useable

Adjust Data Set when necessaryDefine CER/EEREstimate the new object

NOW: CEBoKCost Engineering

Body of Knowledge

2012ISPA & SCEA

are merged intoICEAA

www.iceaaonline.org

About• Association for the Advancement of Cost Engineering -

International

• A not-for-profit organisation• Recommended Practices

17R-97: Cost Estimate Classification System34R-05: Basis of Estimate40R-08: Contingency Estimating: General Principles42R-08: Risk Analysis and Contingency Determination Using Parametric Estimating

• CertificationCertified Cost Consultant™ (CCC™)Certified Cost Engineer™ (CCE™)Certified Estimating Professional™ (CEP™)

• www.aacei.org

Simplified Estimation Model

hours (& money)

measures

risk analysis

risks

consequences

productivity

size

gross hours

influences

Basis of Estimate Quantity Metrics: excavation and backfill quantities, concrete

volumes, piping quantities, ... These may be organized by facilities, process train or manufacturing unit.

Basis of Estimate – Software Services Requirements: number of use cases, number of backlog items,

... Functional size: Function points

Measurement methods: IFPUG, NESMA, COSMIC, FiSMA, … Technical size: (source) lines of code, number of interfaces,

modules, … Service size: number of incidents, tickets, users, locations, …

These may include expected error range, level of accuracy and method of ‘measuring’ (e.g. detailed, extrapolated, estimated, derived)

Size

Basis of Estimate for Software Services

Generalaspects

Basis

Risk

Mitigation

Quality

Mapping to NESMA interest areas

Sizing BasisRequirements

Functionaltechnical

Effort Basisdelivery

constraints, service levels

Planning Basis

Working time standby

Cost Basismethods and

sources , units

BenchmarkingComparisons to

similar engagements

The Tax System Case Study

Basis of Estimate in Practice

H

A

L

na

L

A

H

Good

Poor

Conclusions from supplier perspectiveEstimation (validation)

Consistent structure (e.g. Basis of Estimate)Embedded process

BenchmarkingValidation Estimate / ProposalHistorical data (Internal/External)

MetrificationConsistent approachAuditable calculations (e.g. tool-based)

Management & ControlMetrification (direct data collection)Re-estimation (reflecting direct data)Risk Control

Estimation : The next level

EstimationThe Next Level

And BeyondFrank VogelezangIWSM – Ankara – October 25th 2013

NEtherlands Software Metrics users Association

The next level and beyondWidening the scope from sizing, to cost

drivers, through cost estimation relations to estimating, project control and historical benchmark data.

In cooperation with others like ISBSG, MAIN, DACE, PMI

Products that can be of interest outside the Netherlands will be made available in English

Active working groups with short cycles to deliverEstimation Measurement StandardsEstimating Packaged SoftwareCOSMIC Approximation

I hope to see you next year