Expert Elicitation A Worked Example

Avoiding Bias Basing judgement on all knowledge and consider all available relevant evidence; Consider the widest possibilities for a range of values and not be constrained by a particular value or range; Be prepared to contradict your own previous thinking and statements Be realistic about your level of confidence or experience of a particular subject; Avoid decisions that might be biased towards organisational goals.

Emission Parameters a) % that is Solvent based ink b) % Solvent content of ink c) % inks used in unabated plant d) % lost from abated plant 75% 60% 10% a * b * (c + (1-c) * d) = 85.5

Probability Distribution Functions Lognormal Uniform Triangular Distribution Types: normal MeanMin Max

Sales of Solvent based Inks a) % that is Solvent based ink b) % Solvent content of ink c) % inks used in unabated plant d) % lost from abated plant 75% 60% 10% MinMaxUncertainty Mean 74% - 76% --

60% Solvent 45% Solvent 75% Solvent Most Likely Least Likely 80% ? 40% ? Extremes 65% Solvent 55% Solvent Likely average value range Solvent Content Assessment 55% - 65% +- 8% 60% 10% a) % that is Solvent based ink b) % Solvent content of ink c) % inks used in unabated plant d) % lost from abated plant 75% MinMaxUncertainty Mean 74% - 76% --

13% Assumed 2 additional unabated plant Assumed all 11 plant are abated 40% Assumed all 11 plant are unabated Of 11 unknown plant MinMax Most Likely Least Likely 55% - 65% +- 8% 60% 10% a) % that is Solvent based ink b) % Solvent content of ink c) % inks used in unabated plant d) % lost from abated plant 75% MinMaxUncertainty Mean 74% - 76% -- 7% Known level of unabatement 7% - 13% +- 30% % of solvent Ink consumption in unabated plant

10% 20% Extremes 5%15% Most Likely Least Likely MinMaxUncertainty Mean 55% - 65% +- 8% 60% 10% a) % that is Solvent based ink b) % Solvent content of ink c) % inks used in unabated plant d) % lost from abated plant 75% 74% - 76% -- 7% - 13% +- 30% % losses due to Fugitive 5% - 15% +- 50% MinMax

a) % that is Solvent based ink75% 74% - 76% -- MinMax UncertaintyMean 55% - 65% +- 8% 60%b) % Solvent content of ink 10%c) % inks used in unabated plant 7% - 13% +- 30% 10%d) % lost from abated plant 5% - 15% +- 50% Summary Combining Uncertainties Approach 1 (Equation) Approach 2 (Monte Carlo) 85.5kg/tonne ink +- 29% Use Good Practice Guide

Elicitation Documentation