5.30 Most appraisals will identify some costs and benefits for which there is no readily available market data. In these cases, a range of techniques can be applied to elicit values, even though they may in some cases be subjective. There will be some impacts, such as environmental, social or health impacts, which have no market price, but are still important enough to value separately.
5.31 Box 10 summarises the main techniques that can be used to elicit these values. Annex 2 describes these techniques in more detail, and provides further information on how they are being applied in practice.
BOX 10: VALUATION TECHNIQUES
| Determine whether |
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| Impacts can be measured and quantified |
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| AND |
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| Prices can be determined from market data |
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| If this cannot be |
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| Use 'Willingness to Pay' for a benefit | |
| determined by | 'revealed preference' or a subset of this called 'hedonic pricing' |
| Inferring a price from observing consumer behaviour | |
| If this does not provide values, | |
| Willingness to pay can be estimated by asking | 'stated |
| or whether |
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| In the case of a cost: identifying the amount of compensation consumers | |
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