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141.
142.
Michael R. Crager 《Journal of applied statistics》2012,39(2):399-417
The standardized hazard ratio for univariate proportional hazards regression is generalized as a scalar to multivariate proportional hazards regression. Estimators of the standardized log hazard ratio are developed, with corrections for bias and for regression to the mean in high-dimensional analyses. Tests of point and interval null hypotheses and confidence intervals are constructed. Cohort sampling study designs, commonly used in prospective–retrospective clinical genomic studies, are accommodated. 相似文献
143.
Kurucz G Körmendi A 《Journal of gambling studies / co-sponsored by the National Council on Problem Gambling and Institute for the Study of Gambling and Commercial Gaming》2012,28(1):105-111
Near misses are a special kind of reinforcement which increases one’s desire to play. The aim of this paper is to examine
the perception of near misses in normal population. We used a slot machine simulation running on a PC, where participants
had to play four rounds with different near miss ratios (0, 15, 30 and 45%). Our sample consisted of 159 individuals with
mean age of 22.8 and with no or little gambling experience. For data analysis we used chi-squared goodness-of-fit test and
exact binomial test. Despite the fact, that there was a notable effect of near misses results showed that the subjects could
not perceive trials of them. 相似文献
144.
We develop methodology for a multistage-decision problem with flexible number of stages in which the rewards are survival times that are subject to censoring. We present a novel Q-learning algorithm that is adjusted for censored data and allows a flexible number of stages. We provide finite sample bounds on the generalization error of the policy learned by the algorithm, and show that when the optimal Q-function belongs to the approximation space, the expected survival time for policies obtained by the algorithm converges to that of the optimal policy. We simulate a multistage clinical trial with flexible number of stages and apply the proposed censored-Q-learning algorithm to find individualized treatment regimens. The methodology presented in this paper has implications in the design of personalized medicine trials in cancer and in other life-threatening diseases. 相似文献
145.
146.
Inheritance is a significant means of transferring wealth from one generation to the next, and therefore increasingly attracts attention from researchers and policy-makers working on intergenerational and multidimensional poverty. However, until now disabled persons have been overlooked in these discussions. This oversight is particularly unfortunate because, as a group, the estimated one billion people with disabilities (some 15% of the world’s population) are among the poorest and most marginalized of the global population. Over the past decade, a small but growing literature has examined the recursive connections between poverty and disability throughout the developing world. In this paper, we argue that disabled individuals are routinely denied inheritance rights in many low-income and middle-income countries, and that this is a significant and largely unrecognized contributor to their indigence. The denial of inheritance is both a social justice issue and a practice that can no longer be overlooked if disabled persons are to be brought into the development mainstream. 相似文献
147.
Erks Rebekka L. Allen Joseph A. Harland Lynn K. Prange Kelly 《Voluntas: International Journal of Voluntary and Nonprofit Organizations》2021,32(6):1285-1298
VOLUNTAS: International Journal of Voluntary and Nonprofit Organizations - Many non-profit organizations rely on volunteers to further their mission, but volunteer rates linger at only 25% of the... 相似文献
148.
Jeff Jones Adam Parrish Tom Collins Patrick Chang 《Journal of gay & lesbian social services》2016,28(3):245-254
Objectives: Do short, online educational messages about the human papillomavirus (HPV) influence younger and older men who have sex with men (MSM) differently? Second, what are the HPV knowledge levels and risk perceptions of Southern MSM living outside of major metropolitan areas? Methods: This study draws on participants who completed an anonymous online survey asking about their knowledge, risk assessment, and vaccine acceptance regarding HPV. Results: Knowledge about HPV was low among the MSM in this study. After reading a one-page information intervention, vaccine acceptability increased by a statistically significant amount among both a Younger and Older cohort but risk perception only increased among the younger respondents. Single men regardless of age cohort reported sharper increases in perceived risk after the intervention, but relationship status did not produce significant differences in vaccine acceptability. Conclusion: Online, brief interventions may be effective means of increasing motivation to vaccinate among Southern MSM. 相似文献
149.
Peter Gomber Jascha-Alexander Koch Michael Siering 《Zeitschrift für Betriebswirtschaft》2017,87(5):537-580
Since decades, the financial industry has experienced a continuous evolution in service delivery due to digitalization. This evolution is characterized by expanded connectivity and enhanced speed of information processing both at the customer interface and in back-office processes. Recently, there has been a shift in the focus of digitalization from improving the delivery of traditional tasks to introducing fundamentally new business opportunities and models for financial service companies. Digital Finance encompasses a magnitude of new financial products, financial businesses, finance-related software, and novel forms of customer communication and interaction—delivered by FinTech companies and innovative financial service providers. Against this backdrop, the research on finance and information systems has started to analyze these changes and the impact of digital progress on the financial sector. Therefore, this article reviews the current state of research in Digital Finance that deals with these novel and innovative business functions. Moreover, it gives an outlook on potential future research directions. As a conceptual basis for reviewing this field, the Digital Finance Cube, which embraces three key dimensions of Digital Finance and FinTech, i.e., the respective business functions, the technologies and technological concepts applied as well as the institutions concerned, is introduced. This conceptualization supports researchers and practitioners when orientating in the field of Digital Finance, allows for the arrangement of academic research relatively to each other, and enables for the revelation of the gaps in research. 相似文献
150.
Panos G. Georgopoulos Christopher J. Brinkerhoff Sastry Isukapalli Michael Dellarco Philip J. Landrigan Paul J. Lioy 《Risk analysis》2014,34(7):1299-1316
A challenge for large‐scale environmental health investigations such as the National Children's Study (NCS), is characterizing exposures to multiple, co‐occurring chemical agents with varying spatiotemporal concentrations and consequences modulated by biochemical, physiological, behavioral, socioeconomic, and environmental factors. Such investigations can benefit from systematic retrieval, analysis, and integration of diverse extant information on both contaminant patterns and exposure‐relevant factors. This requires development, evaluation, and deployment of informatics methods that support flexible access and analysis of multiattribute data across multiple spatiotemporal scales. A new “Tiered Exposure Ranking” (TiER) framework, developed to support various aspects of risk‐relevant exposure characterization, is described here, with examples demonstrating its application to the NCS. TiER utilizes advances in informatics computational methods, extant database content and availability, and integrative environmental/exposure/biological modeling to support both “discovery‐driven” and “hypothesis‐driven” analyses. “Tier 1” applications focus on “exposomic” pattern recognition for extracting information from multidimensional data sets, whereas second and higher tier applications utilize mechanistic models to develop risk‐relevant exposure metrics for populations and individuals. In this article, “tier 1” applications of TiER explore identification of potentially causative associations among risk factors, for prioritizing further studies, by considering publicly available demographic/socioeconomic, behavioral, and environmental data in relation to two health endpoints (preterm birth and low birth weight). A “tier 2” application develops estimates of pollutant mixture inhalation exposure indices for NCS counties, formulated to support risk characterization for these endpoints. Applications of TiER demonstrate the feasibility of developing risk‐relevant exposure characterizations for pollutants using extant environmental and demographic/socioeconomic data. 相似文献