Basis of Estimate for Software Services - Ton Dekkers - NESMA najaarsbijeenkomst 2012

1,102
-1

Published on

0 Comments
1 Like
Statistics
Notes
  • Be the first to comment

No Downloads
Views
Total Views
1,102
On Slideshare
0
From Embeds
0
Number of Embeds
1
Actions
Shares
0
Downloads
24
Comments
0
Likes
1
Embeds 0
No embeds

No notes for slide

Basis of Estimate for Software Services - Ton Dekkers - NESMA najaarsbijeenkomst 2012

  1. 1. NESMAWG ESTIMATION
  2. 2. Background NESMA 2020 Vision of expanding the playing field by collaboration AACE International Association for the Advancement of Cost Engineering International www.aacei.org NESMA interactive member session April 2012 Vision of expanding the playing field by collaboration => WG Estimation
  3. 3. Functional Sizing FSM Methods (ISO) IFPUG, NeSMA, FiSMA, Mark II, COSMIC Business Needs, what to do with “points” Benchmarking Estimation Benchmarking: ISBSG International Software Benchmarking Standards Group => ISO standard (based on other industries) Estimation: ??? => standard (based on other industries) Basis of Estimate: Best Practise 34R-05
  4. 4. Estimation Challenges Estimation Process Consistent Controllable Estimation Verification Defendable Comparable Estimation Validation Defendable Benchmark
  5. 5. Purpose Document the overall engagement scope. Communicate the estimator’s knowledge of the engagement by demonstrating an understanding of scope, quality and duration as it relates to cost. Alert the stakeholders to potential cost risks and opportunities. Provide a record of key communications made during estimate preparation. Provide a record of all documents used to prepare the estimate. Act as a source of support during dispute resolutions. Establish the initial baseline for scope, quantities, effort, duration and cost for use in engagement control. Provide the historical relationships between base-lined estimates throughout the project lifecycle. Facilitate the review and validation of the estimates.
  6. 6. Purpose (II)
  7. 7. High Level view-BOE PURPOSE GUIDELINES Software Development, Maintenance & Support, Infrastructure estimation Prepare 1RECOMMENDED Estimate 2 PRACTICE Assumptions, Conditions & Risks 3 Secure Quality 4 Finalise 5 SUPPORTING FOUNDATIONS AACE, MAIN, NESMA
  8. 8. Prepare Purpose Engagement Scope Description Decomposes the solution into its constituent elements; the Product Breakdown Structure (PBS) Methodology Primary estimating methodology (functional size based, expert based, analogy based, process metrics based, parametric) Estimate Classification Cost Estimate Classification System, AACE Practice 17R-97
  9. 9. Estimate Basis Design Estimate deliverables (process); architectural documents Sizing Units (e.g. Functional Size, Technical Size, Support Size) Effort Methods (and tools) used to convert to size into effort Planning Activities, Milestones and Constraints Cost Methods and sources used for determining all unit, effort, subcontract, material and expenditures cost
  10. 10. Assumptions, Conditions & Risks Allowances Assumptions Exclusions Exceptions Anomalies or variances to standard estimating practices Risks and Opportunities Identify those elements with high or very high risk or opportunity values related to cost, duration, quality and/or safety critical measures Containments Measures included to prevent and/or mitigate the identified risks Contingencies Contingency covers inadequacies in complete project scope definition, estimating methods and estimating data
  11. 11. Control & Quality Reconciliation major differences between the new or re-baselined estimate and the last published estimate Benchmarking comparisons of overall estimate metrics, ratios, and factors with similar engagements, historical data, and industry data Quality Assurance Estimating Team Appendices:  Estimate Deliverables Checklist  Reference Documents sizing report, requirements, designs, texts, notes, specifications  Additional Attachments (optional) reconciliation report, benchmarking report, risk analysis report
  12. 12. PURPOSE GUIDELINES Software Development, Maintenance & Support, Infrastructure Estimating Level of detail Engagement Estimate Estimation methodology Stage, Deal Scope Classification purpose (FP, expert, size/type, fixed Description (1,2,3,4,5) etc.) price/TMRECOMMENDED PRACTICE Sizing Basis Effort Basis Design Basis Planning Basis Cost Basis Requirements delivery (Components Working time methods and Functional constraints, lists, units, etc.) standby sources , units technical service levels Exceptions Assumptions Exclusions Risks and Allowances anomalies or internal, No costs Opportunities Not in the Basis variances on external included for… assumptions standard Contingencies Management Reconciliation Benchmarking Containments Uncertainty, Reserve Changes to Comparisons to cost elements unforeseeable changes in previous similar for mitigation elements scope, effort estimation engagements Estimate Quality Attachments Attachments Attachments Attachments Assurance Reviews AACE , MAIN, NESMA
  13. 13. Practical Case Estimating Level of detail Engagement Estimate Estimation methodology Stage, Deal Scope Classification purpose (FP, expert, size/type, fixed Description (1,2,3,4,5) etc.) price/TM RECOMMENDED PRACTICE Sizing Basis Effort Basis Design Basis Planning Basis Cost Basis Requirements delivery (Components Working time methods and Functional constraints, lists, units, etc.) standby sources , units technical service levels Exceptions Assumptions Exclusions Risks and Allowances anomalies or internal, No costs Opportunities Not in the Basis variances on external included for… assumptions standard Contingencies Management Reconciliation Benchmarking Containments Uncertainty, Reserve Changes to Comparisons to cost elements unforeseeable changes in previous similar for mitigation elements scope, effort estimation engagements Estimate Quality Attachments Attachments Attachments Attachments Assurance Reviews
  14. 14. Plan /Schedule Base Document 31-08 done Review (1) NESMA [45 days] 01-09 15-10 done Rework Version 0.3 16-10 31-10 done Review (2) MAIN [45 days] 03-11 16-12 started Rework Version 0.7 17-12 15-01 Review (3) AACE International [45 days] 16-01 28-02 Rework Version 1.0 publication AACE / MAIN 01-06
  15. 15. AcknowledgementWorking Group Estimation Ton Dekkers (Chair) Galorath International Hans Bernink ING Martin Eisma CGI Ray Sadal Capgemini Jelle de Vries Ordina

×