Consumer Demand for Prize-Linked Savings: A Preliminary Analysis

This paper reports on a small-scale survey of the potential American demand for prize-linked savings accounts, an account that awards prizes as part of the saving product’s return. In October 2006, Centra Credit Union launched a prize-linked savings pilot. As part of that initiative, we conducted a mall intercept survey of over 500 people in Clarksville, Indiana, the community where the program was launched. This preliminary data suggests that low-to-moderate income Americans may have substantial demand for prize-linked savings, with a majority of survey participants expressing an interest in opening a prize-linked savings account. As predicted by theory and international experience, interest in prize-linked savings is greatest among people who do not have regular saving habits, who have little actual savings, who play lotteries extensively, and who are optimistic about their futures.

Measurement error caused by spatial misalignment in environmental epidemiology

Copyright @ 2009 Gryparis et al - Published by Oxford University Press.In many environmental epidemiology studies, the locations and/or times of exposure measurements and health assessments do not match. In such settings, health effects analyses often use the predictions from an exposure model as a covariate in a regression model. Such exposure predictions contain some measurement error as the predicted values do not equal the true exposures. We provide a framework for spatial measurement error modeling, showing that smoothing induces a Berkson-type measurement error with nondiagonal error structure. From this viewpoint, we review the existing approaches to estimation in a linear regression health model, including direct use of the spatial predictions and exposure simulation, and explore some modified approaches, including Bayesian models and out-of-sample regression calibration, motivated by measurement error principles. We then extend this work to the generalized linear model framework for health outcomes. Based on analytical considerations and simulation results, we compare the performance of all these approaches under several spatial models for exposure. Our comparisons underscore several important points. First, exposure simulation can perform very poorly under certain realistic scenarios. Second, the relative performance of the different methods depends on the nature of the underlying exposure surface. Third, traditional measurement error concepts can help to explain the relative practical performance of the different methods. We apply the methods to data on the association between levels of particulate matter and birth weight in the greater Boston area.This research was supported by NIEHS grants ES012044 (AG, BAC), ES009825 (JS, BAC), ES007142 (CJP), and ES000002 (CJP), and EPA grant R-832416 (JS, BAC)

Simulated emergence of cyclic sexual-asexual reproduction

Motivated by the cyclic pattern of reproductive regimes observed in some species of green flies (``{\it aphids}''), we simulate the evolution of a population enduring harsh seasonal conditions for survival. The reproductive regime of each female is also seasonal in principle and genetically acquired, and can mutate for each newborn with some small probability. The results show a sharp transition at a critical value of the survival probability in the winter, between a reproductive regime in the fall that is predominantly sexual, for low values of this probability, or asexual, for high values.Comment: 9 pages, 4 figures, requires RevTe

Colony size predicts division of labour in Attine ants

Division of labour is central to the ecological success of eusocial insects, yet the evolutionary factors driving increases in complexity in division of labour are little known. The size–complexity hypothesis proposes that, as larger colonies evolve, both non-reproductive and reproductive division of labour become more complex as workers and queens act to maximize inclusive fitness. Using a statistically robust phylogenetic comparative analysis of social and environmental traits of species within the ant tribe Attini, we show that colony size is positively related to both non-reproductive (worker size variation) and reproductive (queen–worker dimorphism) division of labour. The results also suggested that colony size acts on non-reproductive and reproductive division of labour in different ways. Environmental factors, including measures of variation in temperature and precipitation, had no significant effects on any division of labour measure or colony size. Overall, these results support the size–complexity hypothesis for the evolution of social complexity and division of labour in eusocial insects. Determining the evolutionary drivers of colony size may help contribute to our understanding of the evolution of social complexity

Colony size predicts division of labour in Attine ants

Division of labour is central to the ecological success of eusocial insects, yet the evolutionary factors driving increases in complexity in division of labour are little known. The size–complexity hypothesis proposes that, as larger colonies evolve, both non-reproductive and reproductive division of labour become more complex as workers and queens act to maximize inclusive fitness. Using a statistically robust phylogenetic comparative analysis of social and environmental traits of species within the ant tribe Attini, we show that colony size is positively related to both non-reproductive (worker size variation) and reproductive (queen–worker dimorphism) division of labour. The results also suggested that colony size acts on non-reproductive and reproductive division of labour in different ways. Environmental factors, including measures of variation in temperature and precipitation, had no significant effects on any division of labour measure or colony size. Overall, these results support the size–complexity hypothesis for the evolution of social complexity and division of labour in eusocial insects. Determining the evolutionary drivers of colony size may help contribute to our understanding of the evolution of social complexity

Dissociative experiences in Black people of African and African Caribbean descent in the UK

This thesis was submitted for the award of Master of Philosophy and was awarded by Brunel University LondonBlack people of African and Caribbean descent are 3.3 times more likely to be diagnosed and treated for schizophrenia than their White counterparts are. The reasons why remain unclear, however, Black people living with schizophrenia often give racism as the cause of their health and financial difficulties. A series of within-subjects design and web-based survey methods were used to test the validity of these two scales designed to measure perceived racism and examine the relationship between perceived racism, self-depreciation, and the frequency of dissociative experiences in a nonclinical sample of the Black population in the UK. Self-depreciation, the effects of perceived obsession with aspects of the Black body on future social interaction, and race-related schemas were found to significantly contribute to the frequency of dissociative experiences overall. However, race-related schemas need not be derogatory to undermine identity security in those Black people sensitised to perceived racism. Simply mentioning anything race-related might be sufficient to induce dopamine dysregulation in those sensitised to perceived racism and susceptible to schizophrenia spectrum disorders. Study limitations and implications for health and social care policy are considered

ARRECADAÇÃO E INTELIGÊNCIA ARTIFICIAL: COMO O DIREITO TRIBUTÁRIO BRASILEIRO SE ADEQUARÁ AO TEMPO DOS ROBÔS?

Não há como desacelerar a locomotiva do desenvolvimento tecnológico. Até 2025 um em cada três empregos será substituído por robôs ou inteligência artificial. Haverá como consequência um número elevado de desempregados em um curto espaço de tempo, um impacto socioeconômico acentuado. A substituição de trabalho humano por robôs causa um resultado fiscal negativo, diminuindo de maneira significativa a arrecadação tributária, uma vez que esta substituição reduzirá a arrecadação sobre a folha de salário. O desemprego traçará um cenário de necessário incremento dos investimentos públicos em assistência social exatamente no momento em que a arrecadação será reduzida drasticamente. Faz-se relevante promover esta discussão onde se intenta demonstrar a necessidade de adequação do sistema tributário ao novo paradigma das relações de trabalho - utilização de robôs nas empresas em substituição da mão de obra humana. Por este motivo é necessário adequar a tributação a esta nova realidade com o fim de torná-la mais isonômica. Este trabalho aponta os efeitos positivos e negativos desta inovação disruptivas e possíveis soluções de alterações no sistema tributário brasileiro

The male handicap: male-biased mortality explains skewed sex ratios in brown trout embryos

Juvenile sex ratios are often assumed to be equal for many species with genetic sex determination, but this has rarely been tested in fish embryos due to their small size and absence of sex-specific markers. We artificially crossed three populations of brown trout and used a recently developed genetic marker for sexing the offspring of both pure and hybrid crosses. Sex ratios (SR = proportion of males) varied widely one month after hatching ranging from 0.15 to 0.90 (mean = 0.39 ± 0.03). Families with high survival tended to produce balanced or male-biased sex ratios, but SR was significantly female-biased when survival was low, suggesting that males sustain higher mortality during development. No difference in SR was found between pure and hybrid families, but the existence of sire × dam interactions suggests that genetic incompatibility may play a role in determining sex ratios. Our findings have implications for animal breeding and conservation because skewed sex ratios will tend to reduce effective population size and bias selection estimates

Simulated ecology-driven sympatric speciation

We introduce a multi-locus genetically acquired phenotype, submitted to mutations and with selective value, in an age-structured model for biological aging. This phenotype describes a single-trait effect of the environment on an individual, and we study the resulting distribution of this trait among the population. In particular, our simulations show that the appearance of a double phenotypic attractor in the ecology induces the emergence of a stable polymorphism, as observed in the Galapagos finches. In the presence of this polymorphism, the simulations generate short-term speciation, when mating preferences are also allowed to suffer mutations and acquire selective value.Comment: 11 pages, 5 figures, 1 table, uses package RevTe