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Abstract This paper discusses regression analysis of incomplete event history studies with a focus on simultaneous estimation and variable selection. Such studies are commonly performed in areas such as medical studies and social sciences, and a great deal of literature has been devoted to their analysis except for the problem considered here (Sun and Zhao, 2013). We develop a new method, which will be referred to as a broken adaptive ridge regression approach. We establish its asymptotic properties, including the oracle property and clustering effect. We also report simulation results which indicate that the proposed method performs well, and better than the existing methods, in practice. In addition, an application is provided. [ABSTRACT FROM AUTHOR]

Abstract Repeated measures designs are frequently used for planning experiments in the life or social sciences. Typical examples include the comparison of different treatments over time, where both factor levels may possess an additional structure. For such designs, the statistical analysis typically consists of several steps. If the global null is rejected, multiple comparisons are performed. Usually, general factorial repeated measures designs are inferred by classical linear mixed models. Common underlying assumptions, such as normality or variance homogeneity are, however, often not met in practice. Furthermore, when dealing with, e.g., ordinal or ordered categorical data, means are no longer meaningful to describe an effect and other effect sizes should be used. To this end, we developmultiple contrast tests for nonparametric treatment effects in general factorial repeated measures designs within this paper and equip them with a novel, asymptotically correct wild bootstrap approach. Because regulatory authorities require the calculation of confidence intervals, this work also provides simultaneous confidence intervals for linear contrasts and for the ratio of different contrasts in meaningful effects. Extensive simulations are conducted to foster the theoretical findings. Finally, the analysis of two datasets exemplify the applicability of the novel procedures. [ABSTRACT FROM AUTHOR]

Urgent environmental issues are testing the limits of current management approaches and pushing demand for innovative approaches that integrate across traditional disciplinary boundaries. Practitioners, scholars, and policy-makers alike call for increased integration of natural and social sciences to develop new approaches that address the range of ecological and societal impacts of modern environmental issues. From a theoretical perspective, social-ecological systems (SES) science offers a compelling approach for improved environmental management through the application of transdisciplinary and resilience concepts. A framework for translating SES theory into practice, however, is lacking. In this paper, we define the key components of an SES-based environmental management approach. We offer recommendations for integrating an SES approach into existing environmental management practices. Results presented are useful for management professionals that seek to employ an SES environmental management approach and scholars aiming to advance the theoretical foundations of SES science for practical application. [ABSTRACT FROM AUTHOR]

Abstract: Understanding the ecological consequences of visitor use in parks and how visitors interact with resource conditions is essential for avoiding the impairment of park and protected area resources and visitor experiences. This study combined ecological measures of off-trail resource impacts with social science techniques to understand visitor judgments of ecological impacts and visitors' degree of exposure to impacts. Specifically, this paper reports on a novel integration of techniques that was tested in the Bear Lake Road Corridor of Rocky Mountain National Park, CO, USA in which resource change, as a result of visitor use off designated trails and sites, was assessed and combined with social science and visitor use data. Visual survey techniques were used to understand visitor judgments of ecologically important resource impacts and GPS-tracking of visitor use and behavior allowed for the determination of the degree of visitor's exposure to impaired resources. Results suggest that resource impacts are prevalent and intense throughout the area, but tended to be spatially limited in proximity to attraction sites. Visitors are interacting with resource conditions reported to be unacceptable for significant portions of their hikes. Overall, the work represents an advancement of predictive capabilities when managing park and protected area resources. [Copyright &y& Elsevier]

Abstract: This paper examines the role of mechanical refrigeration in seasonality and structural change in the U.S. hog–corn cycle, 1870–1940. This period covers an era in which the widespread adoption of mechanical refrigeration greatly affected the ability to store and transport perishable commodities. These developments in turn altered the seasonal production and price structure for many commodities, including pork. We use a new class of time series models, time-varying smooth transition autoregressions (TV-STARs), to document both the structural change and the nonlinear features observed in seasonal patterns for the U.S. hog–corn price relationship during the late nineteenth and early twentieth centuries. [Copyright &y& Elsevier]