Estimates of the Health Risk Reductions Associated with Attainment of Alternative Particulate Matter Standards in Two U.S. Cities

As part of its periodic re-evaluation of particulate matter (PM) standards, the U.S. Environmental Protection Agency estimated the health risk reductions associated with attainment of alternative PM standards in two locations in the United States with relatively complete air quality data: Philadelphia and Los Angeles. PM standards at the time of the analysis were defined for particles of aerodynamic diameter less than or equal to 10 microm, denoted as PM-10. The risk analyses estimated the risk reductions that would be associated with changing from attainment of the PM-10 standards then in place to attainment of alternative standards using an indicator measuring fine particles, defined as those particles of aerodynamic diameter less than or equal to 2.5 microm and denoted as PM-2.5. Annual average PM-2.5 standards of 12.5, 15, and 20 microg/m3 were considered in various combinations with daily PM-2.5 standards of 50 and 65 microg/m3. Attainment of a standard or set of standards was simulated by a proportional rollback of "as is" daily PM concentrations to daily PM concentrations that would just meet the standard(s). The predicted reductions in the incidence of health effects varied from zero, for those alternative standards already being met, to substantial reductions of over 88% of all PM-associated incidence (e.g., in mortality associated with long-term exposures in Los Angeles, under attainment of an annual standard of 12.5 microg/m3). Sensitivity analyses and integrated uncertainty analyses assessed the multiple-source uncertainty surrounding estimates of risk reduction.     

Assessing Risk in Graphically Presented Financial Series

It has been argued that traders use their natural sensitivity to the fractal properties of price graphs to assess risk and that they are better able to do this when given price change as well as price level information. This approach implies that risk assessments should be higher when the Hurst exponents are lower, that this relationship should be stronger in the presence of price change information and that risk assessment should depend more strongly on the Hurst exponent than on the standard deviation of the series. Participants in Experiment 1 decided which of two assets was riskier by inspecting graphs of their price series. Graphs with lower Hurst exponents were selected only by those who were less emotionally stable and hence more sensitive to risk. However, when both price series and price change series were presented, the assets with lower Hurst exponents were selected by all participants. In a second experiment, participants were given both price level and price change series for a number of assets and rated the risk of trading in each one. Ratings depended more strongly on Hurst exponents than on other measures of volatility. They also depended on indicators of potential loss. Human risk assessment deviates from the way that risk is measured in modern finance theory: it requires integration of information relevant to both uncertainty and loss aversion, thereby imposing high attentional demands on traders. These demands may impair risk assessment but they can be eased by adding displays of price change information.     

Abusive supervision and the entitled employee

We present two studies that examine the effects of psychological entitlement on employees' ratings of abusive supervision and their behavioral reactions to these perceptions. Study 1 indicated that entitlement was positively associated with ratings of abusive supervision. Perceived abuse was, in turn, associated with upward undermining behaviors and organizational deviance. In Study 2, we re-examined the hypothesized relationships using paired data from employees and their coworkers. The results replicated those from the first study and showed that entitled employees rated supervisors as more abusive than coworkers who shared the same supervisors. Although this variance is likely driven by a combination of perceptual distortion and actual abusive behaviors, the ultimate implication is that psychologically entitled employees are prone to feel that they are victims of abuse and to react in undesirable ways.     

The use of public transportation in urban areas: Toward a causal model

In this study, using the statistical models recently introduced by Goodman, we analyze the reasons why individuals choose the car or public transportation for the journey to work and draw out some of the implications of our analysis for public policy. Building on the work of Schnore, we develop a model in which both structural and individual variables are interrelated and show that the structural contexts within which individuals make decisions about their choice are crucial. We also show that, while status differentials are largely accounted for by income differences, male preferences for the automobile tend not to be due either to the structural variables or to income differences. Our findings suggest that present policies designed to induce people to shift to public transportation for the journey to work are not likely to be effective, since they do nothing to alter present cost differentials between the two modes.     

Time diaries and time data for extension of economic accounts

Economic accounts provide a statistical picture of the economic system. The present Canadian accounts include all production that enters the market place. Additionally, the output of all enterprises, including farms, is included even though this output is not sold. Thus, the measure of output of such items does not vary according to whether such output is sold or consumed by the producer. Government activity is also included, valued at cost. The present accounts do not include household production consumed by the producing household.Two major criticisms, not unrelated, have been leveled at the existing structure of the accounts; namely, that they do not provide an adequate measuring stick for all economic activity, and that they do not provide an adequate measure of economic welfare. As a result of these criticisms there is significant agreement that a number of changes to the accounts would be desirable and perhaps more practical than had previously been contemplated.