Some results on bootstrap prediction intervals

We investigate the construction of a BC_a-type bootstrap procedure for setting approximate prediction intervals for an efficient estimator θ_m of a scalar parameter θ, based on a future sample of size m. The results are also extended to nonparametric situations, which can be used to form bootstrap prediction intervals for a large class of statistics. These intervals are transformation-respecting and range-preserving. The asymptotic performance of our procedure is assessed by allowing both the past and future sample sizes to tend to infinity. The resulting intervals are then shown to be second-order correct and second-order accurate. These second-order properties are established in terms of min(m, n), and not the past sample size n alone.     

Testing a theoretical model of adolescent sexual behavior among rural families in poverty

This was a study of 357 adolescents, aged 13 to 17 years, who resided in a family receiving AFDC in 10 rural counties in Arkansas. The study had a twofold purpose: 1) to examine what elements of social control, social learning, and strain theories predicted 3 measures of sexual behavior; and 2) to test an integrated theoretical model with 2-stage least squares regression to see if it fit the data on the 3 measures of sex. The measures of sexual behavior were frequency of sexual intercourse in the past year, number of sexual partners in the past year, and number of sexual partners in lifetime. Bivariate analyses revealed that the consistent predictors of the 3 measures of sex were age, gender, attachment to mother, beliefs, parental supervision and punishment, family and friend support, frustration, and use of rationalizations. The theoretical model that fit all measures of sex showed that bonding influences sexual behavior through frustration, and that age, gender and rationalizations directly impact behavior.     

The use of resighting data to estimate the rate of population growth of the snail kite in Florida

The rate of population growth ( u ) is an important demographic parameter used to assess the viability of a population and to develop management and conservation agendas. We examined the use of resighting data to estimate u for the snail kite population in Florida from 1997-2000. The analyses consisted of (1) a robust design approach that derives an estimate of u from estimates of population size and (2) the Pradel (1996) temporal symmetry (TSM) approach that directly estimates u using an open-population capture-recapture model. Besides resighting data, both approaches required information on the number of unmarked individuals that were sighted during the sampling periods. The point estimates of u differed between the robust design and TSM approaches, but the 95% confidence intervals overlapped substantially. We believe the differences may be the result of sparse data and do not indicate the inappropriateness of either modelling technique. We focused on the results of the robust design because this approach provided estimates for all study years. Variation among these estimates was smaller than levels of variation among ad hoc estimates based on previously reported index statistics. We recommend that u of snail kites be estimated using capture-resighting methods rather than ad hoc counts.     

Making Sense of New Orleans Flood Trauma Recovery: Ethics, Research Design, and Policy Considerations for Future Disasters

This article details the justification and plans of a research team for studying and helping evacuees of Hurricane Katrina from New Orleans to recover by encouraging experimental participants to disclose information about their related experiences in guided interview sessions. Team members' consideration and practice of ethical principles as researchers dealing with the potentially traumatized victims of a disaster are portrayed. Finally, related recommendations for researchers and policy makers are offered.     

School Size and the Interpersonal Side of Education: An Examination of Race/Ethnicity and Organizational Context*

Objectives. The purpose of this study was to extend research on the connection between school size and student outcomes by examining how school size was related to interpersonal processes and whether the interpersonal effects of school size varied by race/ethnicity. Methods. We applied multilevel modeling techniques to a sample of 14,966 students in 84 schools from the National Longitudinal Study of Adolescent Health. Results. Increasing school size was associated with decreasing student attachment to school and to teachers as well as extracurricular participation. Student attachment and teacher bonding diminished with increasing school size at a decreasing rate (reaching minimums in schools with between 1,700–2,000 students), but extracurricular participation dropped at a steady rate. These patterns did not differ substantially by race/ethnicity. Conclusions. The size of the educational institution influences interpersonal dynamics among actors in the institution and does so similarly across student groups. More generally, this research demonstrates the importance of organizational characteristics for social life.     

Echoes of Veblen's theory of business enterprise in the later development of macroeconomics: Fisher's debt-deflation theory of great depressions and the financial instability theories of minsky and tobin

Irving Fisher's debt-deflation theory of great depressions, first published in 1932 and 1933, was invoked by Hyman Minsky and James Tobin as a crucial precursor of their theories of macroeconomic financial instability. This paper argues that Wesley Mitchell was right to perceive a close intellectual affinity between Fisher's debt-deflation theory and Thorstein Veblen's Theory of Business Enterprise (1904), and that this affinity also exists between Veblen (1904) and the analyses of Minsky and Tobin.     

The WHO/WTO Study on Trade and Public Health: A Critical Assessment

This article provides a brief critical examination of a 2002 report jointly issued by the World Health Organization and the World Trade Organization on WTO law and public health. The author argues that the report is in many respects misleading as to the content of WTO law, as interpreted by the Appellate Body of the WTO, its final court. In particular, the WHO/WTO report systematically understates or underestimates the margins of regulatory autonomy that WTO member states have to make regulations that protect public health.     

U.S. Aviation Regulations Increase Probability of Midair Collisions

A purely stochastic Monte Carlo model is used to compare the relative midair collision course probabilities and mean closing velocities of four systems of rules for aircraft cruising altitudes as a function of altitude error: (1) current U.S. federal rules, (2) random altitudes, and (3) two proposed alternatives to the current rules. This model increments error while: (1) counting collisions among cruising pairs of aircraft following the four rules being tested on random headings between randomly placed airports, and (2) calculating mean closing velocities for each rule. The calculations verify that: (1) federal rules increase collision course probabilities by about four times more than for a chaotic system of aircraft cruising at randomly selected altitudes, (2) risk is directly proportional to the level of compliance, and (3) mean closing velocities resulting from the current rule are slightly less than for random altitudes, while being almost twice as high as for the proposed rules. High closing velocities are shown to increase the collision probability.     

Emerging trends in US retailing

This article examines the trends shaping the retail environment as we enter the next century. A modified delphi approach was used to access managerial perceptions of the changing retail landscape. Changes in consumer markets, price and branding strategy, store formats, retail institutions and applications of technology were derived from the analysis. From this, a series of managerial considerations are proposed to focus retail managers on developing new strategies to position themselves effectively in the new global marketplace.