The Impact Estimation Table

Thursday 19 November 2015

9.00am - 5.00pm, Lunch 12.00pm - 1.00pm - no lunch will be provided.

BCS, 1st Floor, The Davidson Building, 5 Southampton Street, London, WC2E 7HA | Maps
(Approximately 10 minutes walk from Waterloo Station and Charing Cross Station)

BCS Members: Free of charge
Non-Members: £40.00 (including VAT @ 20%)

Speaker: Tom Gilb Hon FBCS

  • A laptop or tablet will be required to participate in the course
  • NO lunch will be provided


The Impact Estimation Table: a tool for planning, prioritisation, management decision making, Strategic Planning and IT architecture - with emphasis on QUALITIES and COSTS

The Impact Estimation Table (IET) is a powerful general free tool developed by Tom Gilb over many decades.

It can be used for a wide variety of purposes, in any situation where ends and means (requirements and designs, objectives and strategies) need to be planned, analysed, presented, and put to quality assurance.

The distinguishing features of IET are that:

  • We quantify all quality and value requirements
  • We quantify the expected impact of all solutions/strategies/deigns/architectures for meeting those requirements.
  • We deal with uncertainties and risks in the estimations.
  • We integrate the costs of the solutions (people, time, money) so we can calculate the ‘value for money’
  • We integrate actual incremental agile feedback into the table to manage projects.
  • We have automated tools to support the method
  • The method is open and free.

The applications of IET are many:

  • Decision making with regard to qualities and values of alternatives. (Value Decision Mode)
  • Presentation of complex technical systems to management in intelligible ways: so they can see the value, the costs, and the risks.
  • IT Architecture: with regard to qualities, risks and costs
  • Project Management of a Value Stream in an Evolutionary learning (Lean and Agile mode)

Syllabus, Course Content:

  • The foundation, ‘quantified requirements’.
  • The process of estimation for any ‘solution’: how good is it?
  • The distinction between quantification and measurement.
  • ‘Real World’ estimates, and ‘relative % to Goal’ estimates.
  • ± uncertainty
  • Evidence for the estimate.
  • Sources of the estimates
  • Credibility of the Estimates
  • Tables: putting related estimate together
  • Calculating the Sum of performance on many requirements and costs
  • Calculating the total effect of a set of solutions on a single requirement
  • The Safety Factor
  • Calculating Value for money, Profitability
  • Presentation of the results graphically
  • Tools for doing Impact estimation
  • Connected Levels of Tables: Organisation - Stakeholders - IT System
  • Examples of Practical Applications
  • Comparison to other similar tools like Quality Function Deployment and Balanced Scorecard.