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作者：Zhang, Tingting; Yin, Qiannan; Caffo, Brian; Sun, Yinge; Boatman-Reich, Dana
作者单位：University of Virginia; Johns Hopkins University; Johns Hopkins University
摘要：We build a new ordinary differential equation (ODE) model for the directional interaction, also called effective connectivity, among brain regions whose activities are measured by intracranial electrocorticography (ECoG) data. In contrast to existing ODE models that focus on effective connectivity among only a few large anatomic brain regions and that rely on strong prior belief of the existence and strength of the connectivity, the proposed high-dimensional ODE model, motivated by statistical...
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作者：Lofland, Chelsea L.; Rodriguez, Abel; Moser, Scott
作者单位：University of California System; University of California Santa Cruz; University of Nottingham
摘要：Roll call data are widely used to assess legislators' preferences and ideology, as well as test theories of legislative behavior. In particular, roll call data is often used to determine whether the revealed preferences of legislators are affected by outside forces such as party pressure, minority status or procedural rules. This paper describes a Bayesian hierarchical model that extends existing spatial voting models to test sharp hypotheses about differences in preferences using posterior pr...
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作者：Alkema, Leontine; Zhang, Sanqian; Chou, Doris; Gemmill, Alison; Moller, Ann-Beth; Fat, Doris Ma; Say, Lale; Mathers, Colin; Hogan, Daniel
作者单位：University of Massachusetts System; University of Massachusetts Amherst; Harvard University; World Health Organization; World Health Organization; University of California System; University of California Berkeley
摘要：The maternal mortality ratio (MMR) is defined as the number of maternal deaths in a population per 100,000 live births. Country-specific MMR estimates are published on a regular basis by the United Nations Maternal Mortality Estimation Inter-agency Group (UN MMEIG) to track progress in reducing maternal deaths and were used to evaluate regional and national performance related to Millennium Development Goal (MDG) 5, which called for a 75% reduction in the MMR between 1990 and 2015. Until 2014,...
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作者：Nolde, Natalia; Ziegel, Johanna F.
作者单位：University of British Columbia; University of Bern
摘要：Conditional forecasts of risk measures play an important role in internal risk management of financial institutions as well as in regulatory capital calculations. In order to assess forecasting performance of a risk measurement procedure, risk measure forecasts are compared to the realized financial losses over a period of time and a statistical test of correctness of the procedure is conducted. This process is known as backtesting. Such traditional backtests are concerned with assessing some ...
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作者：Thibaudeau, Yves; Slud, Eric; Gottschalck, Alfred
作者单位：University System of Maryland; University of Maryland College Park
摘要：The Survey of Income and Program Participation (SIPP) is a survey with a longitudinal structure and complex nonignorable design, for which correct estimation requires using the weights. The longitudinal setting also suggests conditional-independence relations between survey variables and early-versus late-wave employment classifications. We state original assumptions justifying an extension of the partially model-based approach of Pfeffermann, Skinner and Humphreys [J. Roy. Statist. Soc. Ser. ...
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作者：Wang, Jue; Luo, Sheng; Li, Liang
作者单位：University of Texas System; University of Texas Health Science Center Houston; University of Texas System; UTMD Anderson Cancer Center
摘要：In many clinical trials studying neurodegenerative diseases such as Parkinson's disease (PD), multiple longitudinal outcomes are collected to fully explore the multidimensional impairment caused by this disease. If the outcomes deteriorate rapidly, patients may reach a level of functional disability sufficient to initiate levodopa therapy for ameliorating disease symptoms. An accurate prediction of the time to functional disability is helpful for clinicians to monitor patients' disease progres...
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作者：Cantoni, E.; Flemming, J. Mills; Welsh, A. H.
作者单位：University of Geneva; Dalhousie University; Australian National University
摘要：Understanding and reducing the incidence of accidental bycatch, particularly for vulnerable species such as sharks, is a major challenge for contemporary fisheries management worldwide. Bycatch data, most often collected by at-sea observers during fishing trips, are clustered by trip and/ or vessel and typically involve a large number of zero counts and very few positive counts. Though hurdle models are very popular for count data with excess zeros, models for clustered forms have received far...
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作者：Yen, Tso-Jung; Lee, Zong-Rong; Chen, Yi-Hau; Yen, Yu-Min; Hwang, Jing-Shiang
作者单位：Academia Sinica - Taiwan; Academia Sinica - Taiwan; National Chengchi University
摘要：In this paper we develop a statistical method for identifying links of a network from time to event data. This method models the hazard function of a node conditional on event time of other nodes, parameterizing the conditional hazard function with the links of the network. It then estimates the hazard function by maximizing a pseudo partial likelihood function with parameters subject to a user-specified penalty function and additional constraints. To make such estimation robust, it adopts a p...
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作者：Aronow, Peter M.; Samii, Cyrus
作者单位：Yale University; New York University
摘要：This paper presents a randomization-based framework for estimating causal effects under interference between units motivated by challenges that arise in analyzing experiments on social networks. The framework integrates three components: (i) an experimental design that defines the probability distribution of treatment assignments, (ii) a mapping that relates experimental treatment assignments to exposures received by units in the experiment, and (iii) estimands that make use of the experiment ...
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作者：Towe, Ross; Eastoe, Emma; Tawn, Jonathan; Jonathan, Philip
作者单位：Lancaster University; Lancaster University; Royal Dutch Shell
摘要：For safe offshore operations, accurate knowledge of the extreme oceanographic conditions is required. We develop a multi-step statistical downscaling algorithm using data from a low resolution global climate model (GCM) and local-scale hindcast data to make predictions of the extreme wave climate in the next 50-year period at locations in the North Sea. The GCM is unable to produce wave data accurately so instead we use its 3-hourly wind speed and direction data. By exploiting the relationship...
