%0 Journal Article %J Journal of the European Economic Association %D 2022 %T Precise or Imprecise Probabilities? Evidence from Survey Response Related to Late-onset Dementia %A Giustinelli, Pamela %A Charles F Manski %A Molinari, Francesca %K late-onset dementia %K Long-term Care %X We elicit numerical expectations for late-onset dementia and long-term care (LTC) outcomes in the Health and Retirement Study. We provide the first empirical evidence on dementia-risk perceptions among dementia-free older Americans and establish important patterns regarding imprecision of subjective probabilities. Our elicitation distinguishes between precise and imprecise probabilities, while accounting for rounding of reports. Imprecise-probability respondents quantify imprecision using probability intervals. Nearly half of respondents hold imprecise dementia and LTC probabilities, while almost a third of precise-probability respondents round their reports. These proportions decrease substantially when LTC expectations are conditioned on hypothetical knowledge of the dementia state. Among rounding and imprecise-probability respondents, our elicitation yields two measures: an initial rounded or approximated response and a post-probe response, which we interpret as the respondent's true point or interval probability. We study the mapping between the two measures and find that respondents initially tend to over-report small probabilities and under-report large probabilities. Using a specific framework for study of LTC insurance choice with uncertain dementia state, we illustrate the dangers of ignoring imprecise or rounded probabilities for modelling and prediction of insurance demand. %B Journal of the European Economic Association %V 20 %P 187-221 %@ 1542-4766 %G eng %N 1 %R 10.1093/jeea/jvab023 %0 Journal Article %J National Bureau of Economic Research Working Paper Series %D 2019 %T Precise or Imprecise Probabilities? Evidence from Survey Response on Late-onset Dementia %A Giustinelli, Pamela %A Charles F Manski %A Molinari, Francesca %K Dementia %K Probabilities %X We elicit numerical expectations for late-onset dementia in the Health and Retirement Study. Our elicitation distinguishes between precise and imprecise probabilities, while accounting for rounding of reports. Respondents quantify imprecision using probability intervals. Nearly half of respondents hold imprecise dementia probabilities, while almost a third of precise-probability respondents round their reports. We provide the first empirical evidence on dementia-risk perceptions among dementia-free older Americans and novel evidence about imprecise probabilities in a nationally-representative sample. We show, in a specific framework, that failing to account for imprecise or rounded probabilities can yield incorrect predictions of long-term care insurance purchase decisions. %B National Bureau of Economic Research Working Paper Series %V No. 26125 %8 2019 %G eng %U http://www.nber.org/papers/w26125 %R 10.3386/w26125