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81.
Relocation stress syndrome is a nursing diagnosis characterized by symptoms such as anxiety, confusion, hopelessness, and loneliness. It usually occurs in older adults shortly after moving from a private residence to a nursing home or assisted-living facility. The primary purpose of this study was to validate the symptoms of relocation stress syndrome. Eight nursing home residents and 8 assisted-living facility residents were interviewed 2 to 10 weeks after admission, when symptoms of relocation stress syndrome are most likely to appear. Results of this study indicate that the incidence of relocation stress syndrome may be overestimated. More accurate diagnosis and treatment of depression in older adults is needed.  相似文献   
82.
The paper describes a methodology to be used for analysis and design of human activity systems. The methodology is based on an analysis of the decision settings whereas most other decision analysis methodologies are analysing the process. The decision concept is analysed and discussed. A distinction between programmed and programmable as well as non-programmed and non-programmable decisions is proposed. A classification of different information types for decision making is presented. A methodology based on a systemic and systematic analysis of the information requirements of an organization is proposed. This methodology also indicates organizational discrepancies and information imbalances. The methodology focuses the settings of the decisions on all levels of organizations. The methodology can be regarded as a dynamic, learning system. The author proposes further research on the individuals decision making abilities.  相似文献   
83.
Assignment of individuals to correct species or population of origin based on a comparison of allele profiles has in recent years become more accurate due to improvements in DNA marker technology. A method of assessing the error in such assignment problems is présentés. The method is based on the exact hypergeometric distributions of contingency tables conditioned on marginal totals. The result is a confidence region of fixed confidence level. This confidence level is calculable exactly in principle, and estimable very accurately by simulation, without knowledge of the true population allele frequencies. Various properties of these techniques are examined through application to several examples of actual DNA marker data and through simulation studies. Methods which may reduce computation time are discussed and illustrated.  相似文献   
84.
Differential equations have been used in statistics to define functions such as probability densities. But the idea of using differential equation formulations of stochastic models has a much wider scope. The author gives several examples, including simultaneous estimation of a regression model and residual density, monotone smoothing, specification of a link function, differential equation models of data, and smoothing over complicated multidimensional domains. This paper aims to stimulate interest in this approach to functional estimation problems, rather than provide carefully worked out methods.  相似文献   
85.
ABSTRACT

We introduce a new methodology for estimating the parameters of a two-sided jump model, which aims at decomposing the daily stock return evolution into (unobservable) positive and negative jumps as well as Brownian noise. The parameters of interest are the jump beta coefficients which measure the influence of the market jumps on the stock returns, and are latent components. For this purpose, at first we use the Variance Gamma (VG) distribution which is frequently used in modeling financial time series and leads to the revelation of the hidden market jumps' distributions. Then, our method is based on the central moments of the stock returns for estimating the parameters of the model. It is proved that the proposed method provides always a solution in terms of the jump beta coefficients. We thus achieve a semi-parametric fit to the empirical data. The methodology itself serves as a criterion to test the fit of any sets of parameters to the empirical returns. The analysis is applied to NASDAQ and Google returns during the 2006–2008 period.  相似文献   
86.
Lifetime Data Analysis - CD4-based multi-state back-calculation methods are key for monitoring the HIV epidemic, providing estimates of HIV incidence and diagnosis rates by disentangling their...  相似文献   
87.
In survival analysis, one way to deal with non-proportional hazards is to model short-term and long-term hazard ratios. The existing model of this nature has no control over how fast the hazard ratio is changing over time. We add a parameter to the existing model to allow the hazard ratio to change over time at different speed. A nonparametric maximum likelihood approach is used to estimate the model parameters. The existing model is a special case of the extended model when the speed parameter is 0, which leads naturally to a way of testing the adequacy of the existing model. Simulation results show that there can be substantial bias in the estimation of the short-term and long-term hazard ratio if the speed parameter is fixed incorrectly at 0 rather than estimated. The extended model is fitted to three real data sets to shed new insights, including the observation that converging hazards does not necessarily imply the odds are proportional.  相似文献   
88.
The UK Lotto game was introduced in November 1994 with a standard 6/49 format and an entry fee of £1 per ticket. After several years, revenue began to fall despite extensive publicity and a variety of inducements. By 2013, nominal weekly revenue was less than half the 1995 level. In October 2013, the operator doubled the price of a ticket to £2 and made a number of changes to the pay-out structure of smaller prizes. The intent of the changes was to reverse the long downward trend in game revenue by encouraging higher jackpots and offering more pay-out opportunities for each ticket. We use draw by draw revenue and other data to evaluate how players responded to these changes and find that, while ticket sales fell dramatically, total revenue rose following the changes. Primarily this appears to have been the consequence of increased frequency of rollovers (and therefore of more frequent high jackpot draws) rather than ticket price inelasticity. However, although there was a short-term gain in revenue, the changes did not arrest, and indeed seem to have accentuated, the long-run trend decrease in the revenue generated by the game.  相似文献   
89.
This study explores obstacles to navigating the high school-to-labor market transition experienced by Second Generation Caribbean Black Male Youth (CBMY) living in Canada's Greater Toronto Area (GTA). Drawing upon interviews with ten CBMY between the ages of 18–27, the article uses a qualitative phenomenological methodology to understand barriers to education and employment from their perspectives. Studies show that 45% of CBMY drop out of high school while 52% are precariously employed in the GTA [Allahar, A. L. 2010. “The Political Economy of ‘Race’ and Class in Canada’s Caribbean Diaspora.” American Review of Political Economy 8 (2): 54; James, C. E. 2012. Students “at Risk” Stereotypes and the Schooling of Black Boys. Urban Education 47 (2), 464–494.; Lewchuk, W., and M. Lafleche. 2014. Precarious Employment and Social Outcomes. Just Labour: A Canadian Journal of Work and Society, 22, 45–50.; Block and Galabuzi 2011. Canada’s Color Coded Labor market: The Gap for Racialized workers. Canadian Centre for Policy Alternatives?=?Centre Canadien de Politiques alternatives]. The ten interview subjects provide retrospective and introspective counter-narratives that expose the race, class and gender-based barriers that frustrate their efforts to secure stable employment. The study utilizes Critical Race Theory (CRT) and the concept of White Supremacy to challenge the view that educational and employment success is based on color-blindness, merit and hard work. The CBMY counter-narratives examined in this study offer profound insight into dominant ideologies and practices that perpetuate racial biases, and present many valuable suggestions, explicit and implied, regarding how to improve the opportunities, inclusion and well-being of CBMY.  相似文献   
90.
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