Create an illustrative study
Higher dispersion produces a longer right-hand tail.
This is the share of zero responses classified as protests after follow-up questions.
Used only to illustrate simple population aggregation.
Scenario being valued
A one-time payment for a vaccination programme that reduces a clearly specified annual infection risk. Currency values are illustrative pounds in a single price year.
This tool generates synthetic responses for learning. It does not estimate WTP for a real programme.
Synthetic response distribution
Zero responsesPositive responsesMeanMedian
How to interpret the results
Illustrative aggregate benefit = mean WTP per person × relevant population
- The mean reflects every response and is commonly used for welfare aggregation, but it is sensitive to high values in a right-skewed distribution.
- The median describes the middle respondent. It is not a substitute for the mean when estimating an aggregate welfare measure.
- A zero may be a genuine valuation, inability to pay, uncertainty or a protest against the scenario or payment vehicle.
- Protest responses should not be removed automatically. Classification rules and results with alternative treatments should be reported.
- WTP is influenced by income and ability to pay. Aggregate monetary benefit is not a measure of clinical need or equity.
- Real studies require defensible sampling, scenario design, piloting, uncertainty analysis and a stated currency and price year.