Returning tuples that users may be interested in is one of the most important goals for multi-criteria decision making. Top-k queries and skyline queries are two representative queries. A top-k query has its merit of returning a limited number of tuples to users but requires users to give their exact utility functions. A skyline query has its merit that users do not need to give their exact utility functions but has no control over the number of tuples to be returned. In this paper, we study a k-regret query, a recently proposed query, which integrates the merits of the two representative queries. We first identify some interesting geometry properties for the -regret query. Based on these properties, we define a set of candidate points called happy points for the -regret query, which has not been studied in the literature. This result is very fundamental and beneficial to not only all existing algorithms but also all new algorithms to be developed for the k-regret query. Since it is found that the number of happy points is very small, the efficiency of all existing algorithms can be improved significantly. Furthermore, based on other geometry properties, we propose two efficient algorithms each of which performs more efficiently than the best-known fastest algorithm. Our experimental results show that our proposed algorithms run faster than the best-known method on both synthetic and real datasets. In particular, in our experiments on real datasets, the best-known method took more than 3 hours to answer a k-regret query but one of our proposed methods took about a few minutes and the other took within a second.

Until the 1930s, malaria was endemic throughout large swaths of the American South. We used a Poisson mixture model to analyze the decline of malaria at the county level in Alabama (an archetypical Deep South cotton state) during the 1930s. Employing a novel data set, we argue that, contrary to a leading theory, the decline of malaria in the American South was not caused by population movement away from malarial areas or the decline of Southern tenant farming. We elaborate and provide evidence for an alternate explanation that emphasizes the role of targeted New Dealera public health interventions and the development of local-level public health infrastructure. We show that, rather than disappearing as a consequence of social change or economic improvements, malaria was eliminated in the Southern United States in the face of economic dislocation and widespread and deep-seated poverty.

This paper employs the capability approach to explore how Latina/Latino migrants in Central Illinois—an area of the Midwest (or Heartland) that lies outside the traditional metropolitan destinations—were coping with the local effects of the global economic crisis of the late 2000s. The crisis affected the capabilities of Latina/Latino migrants to pursue work that provided sufficient income to meet their families' basic needs. Exacerbating the crisis were high prices for food that persisted in the wake of the food price crisis of 2007/08 and further limited purchasing power. Using a case study, we focus on the migrants' capabilities to have control over their environment through employment and entrepreneurship, as well as agency in use of their income (such as sending remittances), which affects the capabilities of affiliation, respect, and emotions. In the 20 in-depth interviews with migrant women and men, we find that most interviewees reported their hours and pay had been cut. Strategies included cutting back on remittances, turning to self-employment, and some new use of support programs. The strategies had different gender dimensions with implications for capabilities that often made them more challenging for male migrants than female migrants.

We study the effect of public health insurance eligibility on labor supply by exploiting the largest public health insurance disenrollment in the history of the United States. In 2005, approximately 170,000 Tennessee residents abruptly lost public health insurance coverage. Using both across- and within-state variation in exposure to the disenrollment, we estimate large increases in labor supply, primarily along the extensive margin. The increased employment is concentrated among individuals working at least 20 hours per week and receiving private, employer-provided health insurance. We explore the dynamic effects of the disenrollment and find an immediate increase in job search behavior and a steady rise in both employment and health insurance coverage following the disenrollment. Our results suggest a significant degree of "employment lock" - workers employed primarily in order to secure private health insurance coverage. The results also suggest that the Affordable Care Act - which similarly affects adults not traditionally eligible for public health insurance - may cause large reductions in the labor supply of low-income adults.

The most prominent feature of the female labor force across the past hundred years is its enormous growth. But many believe that the increase was discontinuous. Our purpose is to identify the short- and long-run impacts of WWII on the labor supply of women who were currently married in 1950 and 1960. We use mobilization rates for various groups of men (by age, race, fatherhood) to see whether there was a wartime impact. We find that an aggregate mobilization rate produces the largest and most robust impacts on both weeks worked and the labor force participation of married white (non-farm) women. The impact, moreover, was experienced primarily by women in the top half of the education distribution. Women who were married but without children during WWII were the group most impacted by the mobilization rate in 1950, although by 1960 WWII still influenced the labor supply decisions of them as well as those with children during WWII. We end the paper with a resolution between the watershed and revisionist views of the role of WWII on female labor supply.

Urbanization affects the local hydrologic cycle. Accurate methods for quantifying and analyzing the hydrologic effects of urbanization are vital for sustainability research. In this study, continuous annual water balances are constructed for the Mill Creek Watershed, a highly developed catchment in the Cincinnati, Ohio metropolitan area. Annual urban water fluxes are gathered for a period of 41 consecutive years (1970–2010) and compared against predevelopment hydrologic conditions. Findings show that urbanization has increased the annual average volume of water entering and leaving the Mill Creek Watershed by nearly 30 percent; concurrently annual average evapotranspiration has decreased about 20 percent. The computer program Aquacycle is used to simulate the evolution of the local water balance in the Mill Creek catchment from predevelopment to current conditions. Simulations were used to reconstitute over 100-years of water balance data. Results found a significant overall change in the water balance throughout historic development including a reversal of the dominant water output from atmospheric (evapotranspiration) to overland (streamflow/wastewater) in the 1920s. Looking to the future, Aquacycle forecasts through the year 2050 were created for two scenarios: [i] with and [ii] without widespread green infrastructure (i.e., rain barrels, green roofs, porous pavement). The green infrastructure options were tested to explore the effectiveness of decentralized stormwater management for mitigating the hydrologic impacts of urbanization. Results show that widespread implementation of rain barrels has relatively little impact on the overall catchment water balance while green roofs have the greatest impact on the catchment’s hydrologic cycle. The combined effect of all three green infrastructure options show a combined reduction in streamflow and wastewater (10 percent) and a significant rise in evapotranspiration (20 percent) in the Mill Creek Watershed.

In this study, we analyzed age variation in the association between obesity status and US adult mortality risk. Previous studies have found that the association between obesity and mortality risk weakens with age. We argue that existing results were derived from biased estimates of the obesity-mortality relationship because models failed to account for confounding influences from respondents' ages at survey and/or cohort membership. We employed a series of Cox regression models in data from 19 cross-sectional, nationally representative waves of the US National Health Interview Survey (19862004), linked to the National Death Index through 2006, to examine age patterns in the obesity-mortality association between ages 25 and 100 years. Findings suggest that survey-based estimates of age patterns in the obesity-mortality relationship are significantly confounded by disparate cohort mortality and age-related survey selection bias. When these factors are accounted for in Cox survival models, the obesity-mortality relationship is estimated to grow stronger with age.

Background: The high prevalence of hypertension in the US adult population represents a serious public health challenge. High hypertension rates result in substantial cardiovascular morbidity and mortality and in elevated health care expenditures. A better understanding of risk factors for development of hypertension in adults may contribute to hypertension prevention efforts. Currently, it is unclear whether veteran status is associated with hypertension risk in women. The goal of this project was to assess the association between veteran status and risk of developing hypertension in women. Methods: The Integrated Health Interview Series (IHIS) is a harmonized dataset for the U.S. National Health Interview Survey (NHIS). Using the IHIS 1997-2010 dataset, population-based prevalence of hypertension among female veterans was compared to non-veterans. For the purpose of analysis, only Whites and African Americans were included in the sample dataset. Veterans were participants who answered ‘Yes’ to the question, “Have you ever been honorably discharged from active duty in the U.S. Army, Navy, Air Force, Marine Crops, or Coast Guard?” Diagnose of hypertension was self-reported. Regression models were performed to evaluate the association between veteran status and the risk of hypertension. Socio-demographic factors and health behaviors were accounted for in the analysis. Sampling weights that adjust for the complex design of the IHIS were applied to all analyses presented. Statistical analyses were performed using SAS version 9.0. Results: Veteran African American women aged 18-40 years of age had a hypertension prevalence rate of 14.8% while non-veterans had a prevalence rate of 14.2%. In White women the prevalence of hypertension was 8.7% among veterans and 7.9% in non-veteran civilians. Hypertension prevalence in African American women older than 40 was 39.1% among veterans and 56.4% in non-veterans (p<0.0001). In White women of the same age-group the prevalence of hypertension was 37.7% among veterans and 39.6% in non-veteran civilians (p<0.005). After adjusting for age, marital status, poverty level, Body Mass Index (BMI), education, smoking, alcohol drinking, and exercise, African American veterans were 24% less likely to have hypertension than non-veteran civilians with statistical significance (OR 0.76, CI 0.6-0.9). There was a 2% risk reduction for hypertension for White veterans but without statistical significance. Conclusion: The prevalence of hypertension was significantly lower in female veterans than in non-veteran females. African American female veterans were 24% less likely to have hypertension than non-veteran African American females, and this association remained significant after adjusting for socio-demographic and health behavior factors.

The U.S. small business sector is a key engine that drives U.S. competitiveness by employing more than half of its citizens and spawning business innovations that result in high economic growth. In the upcoming years, firms composing the small business sector will increasingly be owned by people of color as the U.S. population becomes more racially and ethnically diverse, and as minority persons start businesses at a faster rate than do their non- minority peers. Yet, small businesses owned by minorities are underperforming small businesses owned by non-minorities. The key ingredients for the success of any small- business are (1) the leadership of a skilled and capable entrepreneur, (2) access to sufficient financial capital to achieve scale, buffer losses and exploit business opportunities, and (3) awareness of and access to markets in which to successfully sell the firm’s products. What do we know about the issues of new and existing minority businesses in achieving and utilizing these ingredients? This study is a literature survey that examines recent scholarly research related to this question. In order to implement appropriate programs and policies that sustain a thriving minority business sector, we must understand the challenges that minority entrepreneurs face. This study analyzes and reports key results from economic-related research conducted related to minority businesses and published in peer reviewed scholarly journals since 2000.

We utilize U.S. same-sex marriage legalization to reexamine the unresolved question of why married men earn higher wages than comparable unmarried men. If this marriage premium operates similarly for homosexual men as it does for heterosexual men, the new-found availability of same-sex marriage creates a unique opportunity to study the determinants of the premium. Using census and ACS data, we fi nd that same-sex marriage legalization in several states is associated with signfi cant increases in the wages of resident gay males. We detect little evidence of productivity-related explanations, suggesting employer discrimination may be the primary cause of the premium.

This study examines how the new urban economy has transformed the structures that impact individual earnings opportunities across place. Using data from the 1990 and 2000 Census, this study is based on two multi-level data sets, each reporting characteristics for approximately 1 million individuals nested within more than 200 Metropolitan Statistical Areas (MSAs). This study examines how inequality varies across MSAs in the US. Associations between MSA-level characteristics, including proportion of employment in new economy sectors, earnings, educational attainment, and inequality, are tested. Strong evidence is found demonstrating strong and statistically significant correlations between new economy indicators and MSA-level inequality, which is measured through an MSA-level Gini index and an earnings ratio. In the last portion of the study, hierarchical linear modeling, which makes it possible to test and control for cross-level interactions, is used to examine how these indicators shape individual earnings across place.

With the ever-increasing use of smartphones and tablet devices, location-based services (LBSs) have experienced explosive growth in the past few years. To scale up services, there has been a rising trend of outsourcing data management to Cloud service providers, which provide query services to clients on behalf of data owners. However, in this data-outsourcing model, the service provider can be untrustworthy or compromised, thereby returning incorrect or incomplete query results to clients, intentionally or not. Therefore, empowering clients to authenticate query results is imperative for outsourced databases. In this paper, we study the authentication problem for location-based arbitrary-subspace skyline queries (LASQs), which represent an important class of LBS applications. We propose a basic Merkle Skyline R-tree method and a novel Partial S4-tree method to authenticate one-shot LASQs. For the authentication of continuous LASQs, we develop a prefetching-based approach that enables clients to compute new LASQ results locally during movement, without frequently contacting the server for query re-evaluation. Experimental results demonstrate the efficiency of our proposed methods and algorithms under various system settings. © 1989-2012 IEEE.

Urbanization affects the local hydrologic cycle. Accurate methods for quantifying and analyzing the hydrologic effects of urbanization are vital for sustainability research. In this study, continuous annual water balances are constructed for the Mill Creek Watershed, a highly developed catchment in the Cincinnati, Ohio metropolitan area. Annual urban water fluxes are generated for a period of 41 consecutive years (1970-2010) and compared against predevelopment hydrologic conditions. Findings show that urbanization has increased the annual average volume of water entering and leaving the Mill Creek Watershed by nearly 30 percent; concurrently annual average evapotranspiration has decreased about 20 percent. The computer program Aquacycle is used to simulate the evolution of the local water balance in the Mill Creek catchment from predevelopment to postdevelopment conditions. Looking to the future, green infrastructure projects (i.e., rain barrels, green roofs, porous pavement, etc.) are incorporated into Aquacycle to assess the potential for alternative stormwater management strategies to mitigate and reverse the hydrologic effects of urbanization. Results show that widespread implementation of rain barrels has relatively little impact on the overall catchment water balance; in contrast, conversion to green roofs has promise for reducing streamflow (6 percent) and wastewater (5 percent) and increasing annual evapotranspiration (8 percent) in the Mill Creek Watershed.

Objectives. To elucidate why the inverse association between education level and mortality risk (the gradient) has increased markedly among White women since the mid-1980s, we identified causes of death for which the gradient increased.Methods. We used data from the 1986 to 2006 National Health Interview Survey Linked Mortality File on non-Hispanic White women aged 45 to 84 years (n = 230 692). We examined trends in the gradient by cause of death across 4 time periods and 4 education levels using age-standardized death rates. Results. During 1986 to 2002, the growing gradient for all-cause mortality reflected increasing mortality among low-educated women and declining mortality among college-educated women; during 2003 to 2006 it mainly reflected declining mortality among college-educated women. The gradient increased for heart disease, lung cancer, chronic lower respiratory disease, cerebrovascular disease, diabetes, and Alzheimers disease. Lung cancer and chronic lower respiratory disease explained 47% of the overall increase.Conclusions. Mortality disparities among White women widened across 1986 to 2006 partially because of causes of death for which smoking is a major risk factor. A comprehensive policy framework should address the social conditions that influence smoking among disadvantaged women.

While innovation is central for understanding development over time, less is known about how innovation aff ects development over space. In this paper we use the establishment of agricultural experiment stations to examine the eff ects of a permanent increase in local research on long-term regional development. Our analysis of county-level agricultural census data from 1870 to 2000 reveals that station establishment increased local land productivity over the medium term, with land one standard deviation closer to research receiving a 36% increase in productivity 20 years later. Research proximity e ffects disappear, however, after 30 to 50 years. Furthermore, while the eff ects of research proximity on extensive and intensive adjustments of producers do persist, they cannot account for the limited persistence of research proximity on land productivity. Instead, changes in the development and diffusion of basic science appear to have reduced the advantages of proximity.

El Consejo de Educación de Puerto Rico (CEPR) contrató a Advantage Business Consulting para estudiar los efectos que tendría en la educación post-secundaria de Puerto Rico un cambio en los fondos de Título IV que pudieran ocurrir como consecuencia de la Ley 112-74, aprobada por el Congreso de Estados Unidos a finales del año 2011. Además, el CEPR solicitó a los investigadores el hacer recomendaciones acerca del rol que debería asumir el sistema de asignación de becas estatales ante los cambios que se preveían inminentes a los desembolsos de Becas Pell. El proyecto “Estudio de los efectos que tendría en la educación post-secundaria de Puerto Rico un cambio en los Fondos de Título IV” surge a raíz de la convocatoria del año 2012 del Consejo de Educación de Puerto Rico para desarrollar investigaciones en torno a la educación superior, bajo el tema “Para estudiar los efectos que tendría en la educación post-secundaria de Puerto Rico un cambio en los Fondos de Título IV y hacer recomendaciones acerca del rol que debiera asumir el sistema de asignación de becas estatales”. El estudio se centró en el diseño, construcción y análisis de dos índices de vulnerabilidad—uno para estudiantes y otro para instituciones—para evaluar los posibles efectos de los cambios al Título IV. Como pasos previos . . .

This summary of the full research report--"Natural" Cultural Districts: A Three-City Study (February 2013)--presents the rationale for the study as well as findings and implications for policy and research. Policy issues noted are: differential ecology of "natural" cultural districts; economic inequality and location advantage; and trends in the development and management of cultural space. Research questions noted are: change in neighborhood cultural ecology over time; new models of cultural production; displacement vs community revitalization; and reconnecting the arts with culture.

We examine the impact of name Americanization on labor market outcomes of migrants by constructing a novel longitudinal data set of immigrant naturalization records in 1930 New York where the full initial sample is observed over time. We find that changing into an American name improves labor market outcomes. Compared to name keepers, migrants who change into more popular American names experience larger occupational upgrading, with gains of up to 14% for changing into very common names such as John or William. We show that our estimates of the returns from name Americanization are causal effects by applying instrumental variable methods where we use an index of linguistic complexity based on Scrabble points to predict changes in name Americanization. Our results highlight the tradeoffs between individual identity and labor market success, suggesting that the assimilation process in the first half of the twentieth century passed through economic as well as cultural assimilation.

Research on coresidence between parents and their adult children in the United States has challenged the myth that elders are the primary beneficiaries, instead showing that intergenerationally extended households generally benefit the younger generation more than their parents. Nevertheless, the economic fortunes of those at the older and younger ends of the adult life course have shifted in the second half of the twentieth century, with increasing financial well-being among older adults and greater financial strain among younger adults. This article uses U.S. census and American Community Survey (ACS) data to examine the extent to which changes in generational financial well-being over the late twentieth and early twenty-first centuries have been reflected in the likelihood of coresidence and financial dependency in parentadult child U.S. households between 1960 and 2010. We find that younger adults have become more financially dependent on their parents and that while older adults have become more financially independent of their adult children, they nevertheless coreside with their needy adult children. We also find that the effect of economic considerations in decisions about coresidence became increasingly salient for younger adults, but decreasingly so for older adults.

This paper examines the association between "active life style" behaviors and health. Health is measured with the widely-used five-category general self-rated health indicator (excellent, very good, good, fair, or poor). Analyses are based on the 2006-2008 and 2010 waves of American Time Use Survey (ATUS). For respondents in the 2010 wave of the ATUS, we also examine three specific health outcomes: whether the individual (1) has hypertension, 2) took pain medication on the diary day, and 3) woke up rested on the diary day. Finally, in 2010 we have measures of ATUS respondents' momentary perception of well-being during each of three randomly selected activities. Our study is the first that we know of to examine the association between health behaviors and general and momentary measures of well-being.