where individuals are indexed by i, prices by j, Takeupijis an indi-cator variable for whether individual i says she would purchase thehealth plan at price j, Priceijis the premium price (rescaled so thatits coefficient represents the percentage-point change in take-upassociated with a $1000 increase in premium price), Xiis a vectorof individual characteristics, and εijis an error term. We clusterstandard errors at the individual level to account for the fact thateach individual has two (Questionnaire B) or three (QuestionnaireA) price observations. We down-weight the latter group so that individuals are not given greater weight merely because they were randomized into Questionnaire A (though this re-weighting leavesthe results essentially unchanged).