An evaluation of intermittently inflated extremity cuffs in preventing the cardiovascular deconditioning of bedrest and water immersion

Inflatable tourniquet effects on cardiovascular deconditioning during bed rest and water immersion studies on human

How Has Hospital Consolidation Affected the Price and Quality of Hospital Care?

Provides an overview of the wave of hospital consolidation in the 1990s and reviews the literature on its effects on the prices, costs, and quality of inpatient care. Analyzes the studies' findings and discusses implications for policy makers

Attraction to Chance in Germany and Australia. An experimental study of cultural differences

This paper explores cultural differences in risky choices between Australian and German students. The focus is not on risk itself, but on tension which is a positive attribute of risky choices. Furthermore, the effects of real versus hypothetical payoffs are analysed. The experiment of this paper shows that in a given set of tension creating choices, Australians do choose tension more often than Germans, while Germans prefer higher tension. Additionally it is shown that real payoffs do make a difference in the data, but the real payoff even increases the effect.

The Relevance of Irrelevant Alternatives: An experimental investigation of risky choices

Experimental economists have discovered various violations of expected utility theory and offered alternative models that can explain laboratory results. This study discovers a new violation in risky choices that cannot be explained by theories like Prospect Theory, Disappoint- ment or Regret Theory. In an experimental setting using a between- subject design, the influence of a dominated alternative on certainty equivalents is shown. One group of subjects was offered a series of choices between a lottery ticket with a 50-50 chance of winning and a sure payoff. A second group was offered the same choice plus a third alternative, that as it turned out was not chosen by any participant. As a result, the average chosen sure payoff in the second group was higher than in the first group. That means, by adding a dominated alternative to a choice set, the certainty equivalent of a lottery is in- creased.

Employment and Adverse Selection in Health Insurance

We construct and test a new model of employer-provided health insurance provision in the presence of adverse selection in the health insurance market. In our model, employers cannot observe the health of their employees, but can decide whether to offer insurance. Employees sort themselves among employers who do and do not offer insurance on the basis of their current health status and the probability distribution over future health status changes. We show that there exists a pooling equilibrium in which both sick and healthy employees are covered as long as the costs of job switching are higher than the persistence of health status. We test and verify some of the key implications of our model using data from the Current Population Survey, linked to information provided by the U.S. Department of Labor about the job-specific human capital requirements of jobs.

Loss Aversion for time: An experimental investigation of time preferences

This paper investigates decisions about inter-temporal tradeoffs. The objective of the study is to explore the valuation of time itself without tradeoffs between time and consequences. In an experimental study subjects made decisions about waiting time, where the time was subject to risk. We find that subjects are risk-seeking for decisions about time, which leads to the conclusion that waiting time is experienced as a loss. Subjects in this experiment show similar choice patters as can be seen in studies about money when losses are involved.

The St. Petersburg Paradox despite risk-seeking preferences: An experimental study

The St. Petersburg is one of the oldest violations of expected utility theory. Thus far, explanations of the paradox aim at small probabili- ties being perceived as zero and the boundedness of utility. This paper provides experimental results showing that neither risk attitudes nor perception of small probabilities explain the paradox. We nd that even in situations where subjects are risk-seeking, the St. Petersburg Paradox exists. This indicates that the paradox lies at the very core of human decision-making processes and cannot be explained by the parameters discussed in previous research so far.

Competition among Hospitals

We examine competition in the hospital industry, in particular the effect of ownership type (for-profit, no-for-profit, government). We estimate a structural model of demand and pricing in the hospital industry in California, then use the estimates to simulate the effect of a merger. California hospitals in 1995 face an average price elasticity of demand of -4.85. Not-for-profit hospitals face less elastic demand and act as if they have lower marginal costs. Their prices are lower than for-profits, but markups are higher. We simulate the effects of the 1997 merger of two hospital chains. In San Luis Obispo County, where the merger creates a near monopoly, prices rise by up to 53%, and the predicted price increase would not be substantially smaller were the chains not-for-profits.analysis of health care markets

Do Instrumental Variables Belong in Propensity Scores?

Propensity score matching is a popular way to make causal inferences about a binary treatment in observational data. The validity of these methods depends on which variables are used to predict the propensity score. We ask: "Absent strong ignorability, what would be the effect of including an instrumental variable in the predictor set of a propensity score matching estimator?" In the case of linear adjustment, using an instrumental variable as a predictor variable for the propensity score yields greater inconsistency than the naive estimator. This additional inconsistency is increasing in the predictive power of the instrument. In the case of stratification, with a strong instrument, propensity score matching yields greater inconsistency than the naive estimator. Since the propensity score matching estimator with the instrument in the predictor set is both more biased and more variable than the naive estimator, it is conceivable that the confidence intervals for the matching estimator would have greater coverage rates. In a Monte Carlo simulation, we show that this need not be the case. Our results are further illustrated with two empirical examples: one, the Tennessee STAR experiment, with a strong instrument and the other, the Connors' (1996) Swan-Ganz catheterization dataset, with a weak instrument.

Entry and Competition in Local Hospital Markets

There has been considerable consolidation in the hospital industry in recent years. Over 900 deals occurred from 1994-2000, and many local markets, even in large urban areas, have been reduced to monopolies, duopolies, or triopolies. This surge in consolidation has led to concern about its effect on competition in local markets for hospital services. In this paper we examine the impact of market structure on competition in local hospital markets -- specifically, does competition increase with the number of firms? We extend the entry model developed by Bresnahan and Reiss to make use of quantity information, and apply it to data on the U.S. hospital industry. The results from the estimation are striking. In the hospital markets we examine, entry leads to markets becoming competitive quickly. Entry reduces variable profits and increases quantity. Indeed, most of the effects of entry come from having a second and possibly a third firm enter the market. The use of quantity information allows us to infer that entry is consumer welfare increasing.