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251.
Ecological Momentary Assessment is an emerging method of data collection in behavioral research that may be used to capture the times of repeated behavioral events on electronic devices, and information on subjects' psychological states through the electronic administration of questionnaires at times selected from a probability-based design as well as the event times. A method for fitting a mixed Poisson point process model is proposed for the impact of partially-observed, time-varying covariates on the timing of repeated behavioral events. A random frailty is included in the point-process intensity to describe variation among subjects in baseline rates of event occurrence. Covariate coefficients are estimated using estimating equations constructed by replacing the integrated intensity in the Poisson score equations with a design-unbiased estimator. An estimator is also proposed for the variance of the random frailties. Our estimators are robust in the sense that no model assumptions are made regarding the distribution of the time-varying covariates or the distribution of the random effects. However, subject effects are estimated under gamma frailties using an approximate hierarchical likelihood. The proposed approach is illustrated using smoking data.  相似文献   
252.
ABSTRACT

We consider the problem of hypothesis testing in the situation where the first hypothesis is simple and the second one is local one-sided composite. Wedescribe the choice of the thresholds and the power functions of different tests when the intensity function of the observed inhomogeneous Poisson process has two different types of singularity: cusp and discontinuity. The asymptotic results are illustrated by numerical simulations.  相似文献   
253.
This article investigates the relationship among nonprofit foundations’ choice of philanthropic strategy (expressive, receptive, proactive, and collaborative) and sound governance, as measured by board capital (competencies and networks), board processes (planning, control, evaluation, and so on), and chairman power (entrenchment and tenure). Using a sample of fifty‐one Italian foundations of banking origins, this article shows that high levels of board capital, complete board processes, and chairman long tenure are positively associated with proactive and collaborative philanthropic strategies.  相似文献   
254.
Women have been often invisible in urban planning. Col·lectiu Punt 6, a feminist organisation of women architects and urban planners based in Barcelona, Spain, has developed planning techniques and tools to include women both as objects and subjects of urban planning, and as experts of everyday life. The article focuses on the participatory tools that Col·lectiu Punt 6 has developed that can be used in the different stages of planning, from assessing to evaluating planning policies and interventions, as well as tools of women's empowerment with the goal of promoting bottom-up models of planning. Evidence is shown of how, using these tools, planning becomes more inclusive not only of women in their diversity, but also of children, youth, the elderly, as well as people of different race, ethnicity, income, sexual and gender identities, and capacities. Examples from different contexts are provided, from Spain and Latin America.  相似文献   
255.
How do people form place attachments through interaction with others and with places over time? I propose that there are seven distinct processes through which people form bonds with places. This framework was developed from the analysis of 104 depth interviews conducted in California and Colorado, newspaper and magazine columns and letters, memoirs, and first person essays. This framework proposes that seven distinct processes interact at the individual, group, and cultural level to shape place attachment. Each of the seven processes has a unique nature and develops differently over time and space.  相似文献   
256.
Variability in hospital occupancy negatively impacts the cost and quality of patient care delivery through increased emergency department (ED) congestion, emergency blockages and diversions, elective cancelations, backlogs in ancillary services, overstaffing, and understaffing. Controlling inpatient admissions can effectively reduce variability in hospital occupancy to mitigate these problems. Currently there are two major gateways for admission to a hospital: the ED and scheduled elective admission. Unfortunately, in highly utilized hospitals, excessive wait times make the scheduled gateway undesirable or infeasible for a subset of patients and doctors. As a result, this group often uses the ED gateway as a means to gain admission to the hospital. To better serve these patients and improve overall hospital functioning, we propose creating a third gateway: an expedited patient care queue. We first characterize an optimal admission threshold policy using controls on the scheduled and expedited gateways for a new Markov decision process model. We then present a practical policy based on insight from the analytical model that yields reduced emergency blockages, cancelations, and off‐unit census via simulation based on historical hospital data.  相似文献   
257.
A bandit problem with infinitely many Bernoulli arms is considered. The parameters of Bernoulli arms are independent and identically distributed random variables from a generalized beta distributionG3B(a, b, λ) witha, b>0 and 0<λ<2. Under the generalized beta prior distributions, we first derive the asymptotic expected failure rates ofk-failure strategies, and then obtain a lower bound for the expected failure rate over all strategies investigated in Berry et al. (1997). The asymptotic expected failure rates for the other three strategies studied in Berry et al. (1997) are also included. Numerical estimations for a variety of generalized beta prior distributions are presented to illustrate the performances of these strategies.  相似文献   
258.
Survival data with one intermediate state are described by semi-Markov and Markov models for counting processes whose intensities are defined in terms of two stopping times T 1< T 2. Problems of goodness-of-fit for these models are studied. The test statistics are proposed by comparing Nelson–Aalen estimators for data stratified according to T 1. Asymptotic distributions of these statistics are established in terms of the weak convergence of some random fields. Asymptotic consistency of these test statistics is also established. Simulation studies are included to indicate their numerical performance.  相似文献   
259.
Marshall–Olkin semi-Burr and Marshall–Olkin Burr distributions are introduced and studied. Their various characteristics in reliability analysis are derived. Applications in time series analysis are discussed.  相似文献   
260.
This paper concerns the estimation of the offspring mean vector, the covariance matrix and the growth rate in the class of bisexual branching processes with population‐size dependent mating. For the proposed estimators, some unconditional moments and some conditioned to non‐extinction are determined and asymptotic properties are established. Confidence intervals are obtained and, as illustration, a simulation example is given.  相似文献   
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