This paper reports the results of a statistical summary of estimates of the marginal willingness to pay (MWTP) for reducing particulate matter from hedonic property value models developed between 1967 and 1988. Results using both ordinary least squares and minimum absolute deviation estimators suggest that market conditions and the procedures used to implement the hedonic models were important to the resulting MWTP estimates. The interquartile range for these estimated marginal values (measured as a change in asset prices) lies between zero and $98.52 (in 1982-84 dollars) for a one-unit reduction in total suspended particulates (in micrograms per cubic meter). The mean MWTP is nearly five times the median ($109.90 vs. $22.40), suggesting that outliers are important influences to any summary statistics for these estimates.

This paper reports the results of a statistical summary of estimates of the marginal willingness to pay (MWTP) for reducing particulate matter from hedonic property value models developed between 1967 and 1988. Results using both ordinary least squares and minimum absolute deviation estimators suggest that market conditions and the procedures used to implement the hedonic models were important to the resulting MWTP estimates. The interquartile range for these estimated marginal values (measured as a change in asset prices) lies between zero and $98.52 (in 1982-84 dollars) for a one-unit reduction in total suspended particulates (in micrograms per cubic meter). The mean MWTP is nearly five times the median ($109.90 vs. $22.40), suggesting that outliers are important influences to any summary statistics for these estimates.

The professions constitute an intellectual elite. Hence, it is of interest how women fare in this elite. This study attempts to explain differences among states of the proportion of women in the professions based on the 1960 census. This is done with demand and supply equations using the following variables: state per capita income, industrial structure, female educational endowment, availability of domestics, and ratio of male to female professional income. All of the variables performed well except the income variable. The poor performance of the latter seems to be due to its aggregative character and necessary statistical manipulations.

In a recent article in this Journal, Cummings al. (1997) offer experimental evidence rejecting the hypothesis that a hypothetical referendum is an incentive‐compatible mechanism for obtaining the social value of, or willingness to pay for, changes in the allocation of environmental goods and services. While cautions in offering a blanket rejection of hypothetical referenda as a means of measuring economic values on the basis of their findings, the authors do suggest that at least in experimental settings respondents appear to behave differently when real money is changing hands. Wheather hypothetical situations adequately mimic real‐market situations has been debated in the contigent valuation literature since its inception (see Cummings, Brookshire, and Schulze 1986). Cummings et al.'s finding of incentive incompatibility appears to offer strong evidence for the critics of hypothetical referenda.