12,968 research outputs found
Passive solar reflector satellite revisited
Passive light weight reflectors in space which direct the incident solar energy to a specified location on the Earth surface are proposed as an alternative system for the solar power satellite to overcome conversion losses and to avoid the need for photovoltaic cells. On Earth, either photovoltaic cells or a steam turbine alternator on a solar tower, or a similar conventional, relatively high efficiency cycle are used for electricity generation. The constraints which apply to the design of the optical system if a single satellite is placed in geostationary orbit are outlined. A single lens and a two lens system are discussed
Keeping up with the Joneses and staying ahead of the Smiths: evidence from suicide data
This paper empirically assesses the theory of interpersonal income comparison using a unique data set on suicide deaths in the United States. We treat suicide as a choice variable, conditional on exogenous risk factors, reflecting one's assessment of current and expected future utility. Using this framework we examine whether differences in group-specific suicide rates are systematically related to income dispersion, controlling for socio-demographic characteristics and income level. The results strongly support the notion that individuals consider relative income in addition to absolute income when evaluating their own utility. Importantly, the findings suggest that relative income affects utility in a two-sided manner, meaning that individuals care about the incomes of those above them (the Joneses) and those below them (the Smiths). Our results complement and extend those from studies using subjective survey data or data from controlled experiments.Income distribution
Happiness, unhappiness, and suicide: an empirical assessment
The use of subjective well-being (SWB) data for investigating the nature of individual preferences has increased tremendously in recent years. There has been much debate about the cross-sectional and time series patterns found in these data, particularly with respect to the relationship between SWB and relative status. Part of this debate concerns how well SWB data measures true utility or preferences. In a recent paper, Daly, Wilson, and Johnson (2007) propose using data on suicide as a revealed preference (outcome-based) measure of well-being and find strong evidence that reference-group income negatively affects suicide risk. In this paper, we compare and contrast the empirical patterns of SWB and suicide data. We find that the two have very little in common in aggregate data (time series and cross-sectional), but have a strikingly strong relationship in terms of their determinants in individual-level, multivariate regressions. ; This latter result cross-validates suicide and SWB micro data as useful and complementary indicators of latent utility.Happiness ; Suicide
How Working age People with Disabilities Fared over the 1990s Business Cycle
Using data from the March Current Population Survey (CPS) we show that while the longest peacetime economic expansion in United States history has increased the economic well-being of most Americans, the majority of working age men and women with disabilities have been left behind. Robust economic growth since the recession of the early 1990s has lifted nearly all percentiles of the income distribution of working age men and men without disabilities beyond their previous business cycle peak levels of 1989. In contrast, the majority of working age men and women with disabilities did not share in economic growth over this period. Not only did their employment and labor earnings fall during the recession of the early 1990s but their employment and earnings continued to fall during the economic expansion that followed
Relative status and well-being: evidence from U.S. suicide deaths
This paper empirically assesses the theory of interpersonal income comparison using individual level data on suicide deaths in the United States. We model suicide as a choice variable, conditional on exogenous risk factors, reflecting an individual's assessment of current and expected future utility. Our empirical analysis considers whether suicide risk is systematically related to the income of others, holding own income and other individual factors fixed. We estimate proportional hazards and probit models of the suicide hazard using two separate and independent data sets: (1) the National Longitudinal Mortality Study and (2) the Detailed Mortality Files combined with the 5 percent Public Use Micro Sample of the 1990 decennial census. Results from both data sources show that, controlling for own income and individual characteristics, individual suicide risk rises with reference group income. This result holds for reference groups defined broadly, such as by county, and more narrowly by county and one demographic marker (e.g., age, sex, race). These findings are robust to alternative specifications and cannot be explained by geographic variation in cost of living, access to emergency medical care, mismeasurement of deaths by suicide, or by bias due to endogeneity of own income. Our results confirm findings using self-reported happiness data and are consistent with models of utility featuring "external habit" or "Keeping Up with the Joneses" preferences.Income distribution ; Suicide
Economics of Disability Research Report #5: Economic Outcomes of Working-Age People with Disabilities over the Business Cycle – an Examination of the 1980s and 1990s
We examine the rate of employment and the household income of the working-age population (aged 25-61) with and without disabilities over the business cycles of the 1980s and 1990s using data from the March Current Population Survey and the National Health Interview Survey. In general, we find that while the employment of working-age men and women with and without disabilities exhibited a procyclical trend during the 1980s business cycle, this was not the case during the 1990s expansion. During the 1990s, the employment of working-age men and women without disabilities continued to be procyclical, but the employment rates of their counterparts with disabilities declined over the entire 1990s business cycle. Although increases in disability transfer income replaced a significant fraction of their lost earnings, the household income of men and women with disabilities fell relative to the rest of the population over the decade
Dry Friction due to Adsorbed Molecules
Using an adiabatic approximation method, which searches for Tomlinson
model-like instabilities for a simple but still realistic model for two
crystalline surfaces in the extremely light contact limit, with mobile
molecules present at the interface, sliding relative to each other, we are able
to account for the virtually universal occurrence of "dry friction." The model
makes important predictions for the dependence of friction on the strength of
the interaction of each surface with the mobile molecules.Comment: four pages of latex, figure provide
The happiness - suicide paradox
Suicide is an important scientific phenomenon. Yet its causes remain poorly understood. This study documents a paradox: the happiest places have the highest suicide rates. The study combines findings from two large and rich individual-level data sets—one on life satisfaction and another on suicide deaths—to establish the paradox in a consistent way across U.S. states. It replicates the finding in data on Western industrialized nations and checks that the paradox is not an artifact of population composition or confounding factors. The study concludes with the conjecture that people may find it particularly painful to be unhappy in a happy place, so that the decision to commit suicide is influenced by relative comparisons.Happiness ; Suicide
Optimal indicators of socioeconomic status for health research
Objectives: This paper examines the relationship between various measures of SES and mortality for a representative sample of individuals. ; Methods: Data are from the Panel Study of Income Dynamics. Sample includes 3,734 individuals aged 45 and above who participated in the 1984 interview. Mortality was tracked between 1984 and 1994 and is related to SES indicators using Cox event-history regression models. ; Results: Wealth has the strongest associations with subsequent mortality, and these associations differ little by age and sex. Other economic measures, especially family-size-adjusted household income, have significant associations with mortality, particularly for nonelderly women. ; Conclusions: By and large, the economic components of SES have associations with mortality that are at least as strong as, and often stronger than, more conventional components (e.g., completed schooling, occupation).Income distribution
- …