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61.
Juvenile crime affects not only the victims of the crime but also the delinquents’ future. How to prevent adolescent criminal behavior has become an important public policy issue. This study contributes to this interesting issue by examining the relationship between tattooing and adolescents’ criminal behavior. In particular, this study investigates whether or not having a tattoo/tattoos is connected to the incidence of various criminal activities, including: larceny, robbery, fraud, assault, drug use, and homicide. A unique sample of 973 juvenile detainees drawn from the administrative profiles in Taiwan and the coarsened exact matching method were utilized. Results show that compared to their nontattooed counterparts, tattooed juvenile detainees were significantly more likely to commit fraud, assault, drug abuse, and homicide by 3%, 13%, 9%, and 9%, respectively. In contrast, tattooing was not significantly associated with larceny or robbery. From a policy perspective, given the significant link between tattooing and criminal behavior, the presence of a tattoo in adolescents may serve as a valuable indicator regarding adolescents’ high probability of committing crimes.  相似文献   
62.
This paper provides a critique of existing research on the internationalization process of the firm and proposes an agenda for future inquiry. In recent years, process approaches have received increasing attention in management research, leading to a more refined understanding of the distinction between process and variance paradigms. We apply a process lens to a well‐established sub‐field of international business, namely the internationalization process of the firm. We review how this research tradition has evolved over four decades. The review commences with a reassessment of the seminal ‘stage models’ that date back to the 1970s. It then proceeds to classify subsequent research on the basis of whether it includes process data and/or process theorizing. It is found that the majority of studies in this review do not combine process data with process theorizing. We show how, even in studies that contain some process elements, a process approach is not always sustained throughout the paper. On the basis of this review, six research themes are proposed, which would form the basis for a process agenda for future research.  相似文献   
63.
Several colorectal cancer (CRC) screening models have been developed describing the progression of adenomas to CRC. Currently, there is increasing evidence that serrated lesions can also develop into CRC. It is not clear whether screening tests have the same test characteristics for serrated lesions as for adenomas, but lower sensitivities have been suggested. Models that ignore this type of colorectal lesions may provide overly optimistic predictions of the screen‐induced reduction in CRC incidence. To address this issue, we have developed the Adenoma and Serrated pathway to Colorectal CAncer (ASCCA) model that includes the adenoma‐carcinoma pathway and the serrated pathway to CRC as well as characteristics of colorectal lesions. The model structure and the calibration procedure are described in detail. Calibration resulted in 19 parameter sets for the adenoma‐carcinoma pathway and 13 for the serrated pathway that match the age‐ and sex‐specific adenoma and serrated lesion prevalence in the COlonoscopy versus COlonography Screening (COCOS) trial, Dutch CRC incidence and mortality rates, and a number of other intermediate outcomes concerning characteristics of colorectal lesions. As an example, we simulated outcomes for a biennial fecal immunochemical test screening program and a hypothetical one‐time colonoscopy screening program. Inclusion of the serrated pathway influenced the predicted effectiveness of screening when serrated lesions are associated with lower screening test sensitivity or when they are not removed. To our knowledge, this is the first model that explicitly includes the serrated pathway and characteristics of colorectal lesions. It is suitable for the evaluation of the (cost)effectiveness of potential screening strategies for CRC.  相似文献   
64.
Abstract

This article responds to the call for producing activist-oriented scholarship by engaging with theoretical and methodological approaches that explore the inclusion of women and girls with disabilities in Vietnam. We consider possibilities for connecting different forms of knowledge and activism by reflecting on research practices designed to foster social change. Specifically, we ask: how can critical disability studies be more reflexive about knowledge which privileges particular ways of knowing from the Global North? What alternative possibilities can exist to foster more inclusive and transformative knowledge that tackles systemic forms of oppressions in colonial and postcolonial contexts? Reflecting on an ongoing collaborative project in Vietnam, we argue that critical disability studies which engages with different forms of activism through critical reflections on our privileges can tackle exclusion by opening a new platform for debating social justice transnationally.  相似文献   
65.
The U.S. Prohibition experience shows a remarkable policy reversal. In only 14 years, a drastic shift in public opinion required two constitutional amendments. I develop and estimate a model of endogenous law enforcement, determined by beliefs about the Prohibition‐crime nexus and alcohol‐related moral views. In turn, the policy outcomes shape subsequent learning about Prohibition enforcement costs. I estimate the model through maximum likelihood on Prohibition Era city‐level data on police enforcement, crime, and alcohol‐related legislation. The model can account for the variation in public opinion changes, and the heterogeneous responses of law enforcement and violence across cities. Results show that a 15% increase in the homicide rate can be attributed to Prohibition enforcement. The subsequent learning‐driven adjustment of local law enforcement allowed for the alcohol market to rebound to 60% of its pre‐Prohibition size. I conclude with counterfactual exercises exploring the welfare implications of policy learning, prior beliefs, preference polarization, and alternative political environments. Results illustrate the importance of incorporating the endogenous nature of law enforcement into our understanding of policy failure and policy success.  相似文献   
66.
Mini-batch algorithms have become increasingly popular due to the requirement for solving optimization problems, based on large-scale data sets. Using an existing online expectation–maximization (EM) algorithm framework, we demonstrate how mini-batch (MB) algorithms may be constructed, and propose a scheme for the stochastic stabilization of the constructed mini-batch algorithms. Theoretical results regarding the convergence of the mini-batch EM algorithms are presented. We then demonstrate how the mini-batch framework may be applied to conduct maximum likelihood (ML) estimation of mixtures of exponential family distributions, with emphasis on ML estimation for mixtures of normal distributions. Via a simulation study, we demonstrate that the mini-batch algorithm for mixtures of normal distributions can outperform the standard EM algorithm. Further evidence of the performance of the mini-batch framework is provided via an application to the famous MNIST data set.  相似文献   
67.
The mean residual life (MRL) function is one of the basic parameters of interest in survival analysis that describes the expected remaining time of an individual after a certain age. The study of changes in the MRL function is practical and interesting because it may help us to identify some factors such as age and gender that may influence the remaining lifetimes of patients after receiving a certain surgery. In this paper, we propose a detection procedure based on the empirical likelihood for the changes in MRL functions with right censored data. Two real examples are also given: Veterans' administration lung cancer study and Stanford heart transplant to illustrate the detecting procedure. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
68.
In survival analysis, we sometimes encounter data with multiple censored outcomes. Under certain scenarios, partial or even all covariates have ‘similar’ relative risks on the multiple outcomes in the Cox regression analysis. The similarity in covariate effects can be quantified using the proportionality of regression coefficients. Identifying the proportionality structure, or equivalently whether covariates have individual or collective effects, may have important scientific implications. In addition, it can lead to a smaller set of unknown parameters, which in turn results in more accurate estimation. In this article, we develop a novel approach for identifying the proportionality structure. Simulation shows the satisfactory performance of the proposed approach and its advantage over estimation under no assumed structure. We analyse three datasets to demonstrate the practical application of the proposed approach.  相似文献   
69.
A problem of using a non‐convex penalty for sparse regression is that there are multiple local minima of the penalized sum of squared residuals, and it is not known which one is a good estimator. The aim of this paper is to give a guide to design a non‐convex penalty that has the strong oracle property. Here, the strong oracle property means that the oracle estimator is the unique local minimum of the objective function. We summarize three definitions of the oracle property – the global, weak and strong oracle properties. Then, we give sufficient conditions for the weak oracle property, which means that the oracle estimator becomes a local minimum. We give an example of non‐convex penalties that possess the weak oracle property but not the strong oracle property. Finally, we give a necessary condition for the strong oracle property.  相似文献   
70.
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