Expert Opinion Technique Chapter 12 1 Introduction Expert

Expert Opinion Technique Chapter 12 1

Introduction • Expert Opinion techniques involves consultation with experts, who use their experience and understanding of the system to arrive at an estimate of its cost. • Only used when more objective techniques are not applicable • Used to corroborate or adjust objective data – Cross check historical based estimate • Use for high level, low fidelity estimating • Last resort Tip: Expert opinion is the least regarded and most dangerous method, but it is seductively easy. Most lexicons do not even admit it as a technique, but it is included here for completeness. 2

Expert Opinion – Advantages/Disadvantages • Advantages – An expert can factor in differences between past project experiences and new techniques, architectures or applications involved in the future project – Good cross check of other estimate from Subject Matter Expert (SME) point of view – Allows perspective to an estimate that may be overlooked without SME • Disadvantages – Expert judgment is only as good as the estimator, who has his own biases – Completely subjective without use of other techniques – Low-to-nil credibility 3

Uses of Expert Opinion • Business Forecasting – Creating technological forecasts 10 to 20 years in the future. – Do. D uses this to estimate basic research funding. • Estimating parameters for CERs: – Software lines of code – Flying hours – Deployment schedule • Evaluating contractor proposals. • Estimating cost relationships. • Identifying and specifying cost drivers. 4

What makes a good expert? • Credibility! • Someone who has the ear of the Program manager. – You should use the same person that the program manager relies upon for the most critical information. • Technical specialist or engineer who is knowledgeable about the program under question. 5

What should you ask for? • Technical, Schedule and Quantity information. – What areas of the program are most volatile? – What parameters are most likely to drive program costs? – What are the analogous systems? » Quantify relationships with factors. – What are the inputs for CERs and cost models? » Weight, power, performance, etc. – What are the bounds of uncertainty associated with their estimates? • Never ask for dollar estimates! That is the Cost Estimator’s job. Technical specialists are experts in technical parameters or program issues. It is the Cost Estimator’s job to translate these into cost estimates. 6

Subjects to address with functional experts • • . Ground Rules and Assumptions - potential areas they believe will impact the basis of your estimate. They know what areas of the program are most volatile. Write down everyone they can list so no incorrect assumptions are made by anyone. Cost Drivers - identify which parameters are most apt to drive program costs. Not necessarily “how much” each drives cost but explores the “influence” of a variable. Analogous System and Related Factors - identify the closest system or subsystem to your program and quantify those relationships with a factor. Inputs to CERs and Cost Models - what are the technical parameters such as weight, power, performance characteristics, etc. Percent Complete - the functional specialists should be able to provide you with the estimate of how complete an in-process contract is. This will allow you to allocate the sunk costs to the percent complete and extrapolate for the remaining effort. Inputs to Risk and Sensitivity Analysis - inquire as to the range or “bounds” of uncertainty/risk associated with data they provide or the overall program. Inputs to Time Phasing Methodologies - have them identify key milestones and the percentage of effort associated with each one. This will help plot the outlay profile. 7

What to know before starting. . . • If you are requesting data to use in some CERs or models, you must know what those inputs mean. – Weight in pounds or kilograms? – Peak power or average power? • Things to keep in mind as you approach a technical specialist for information. – What specific information do you want to obtain? – Is this the right person to ask? – What are your specific questions? – The art of communication! » Keep in mind that anything can be misunderstood. 8

How to obtain information • It helps to be a good lawyer and a good detective. • Ask clear, logical, probing questions. • Never simply ask a question then just walk away, use the following approach… – Help the specialists think through their own answers. » “Do you mean…? ” » “Would that be the same in another situation? ” – Ask questions in more than one way. » Clarification. » Their answers might change based on a clarification question. – Look for uncertainty in their answers. » Was their response confident or reluctant? – Evaluate the information obtained. » Make sense? Could you explain it to someone else? 9