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Practice makes perfect: the consequences of lexical proficiency for articulation

LINGUISTICS VANGUARD 2018年第S2期4卷

作者： Tomaschek, Fabian Tucker, Benjamin V. Fasiolo, Matteo Baayen, R. Harald Univ Tubingen Dept Quantitat Linguist Tubingen Germany Univ Alberta Dept Linguist Edmonton AB Canada Univ Bristol Sch Math Bristol Avon England

Many studies report shorter acoustic durations, more coarticulation and reduced articulatory targets for frequent words. This study investigates a factor ignored in discussions on the relation between frequency and phonetic detail, namely, that motor skills improve with experience. Since frequency is a measure of experience, it follows that frequent words should show increased articulatory proficiency. We used EMA to test this prediction on German inflected verbs with [a] as stem vowels. Modeling median vertical tongue positions with quantile regression, we observed significant modulation by frequency of the U-shaped trajectory characterizing the articulation of the [a:]. These modulations reflect two constraints, one favoring smooth trajectories through anticipatory coarticulation, and one favoring clear articulation by realizing lower minima. The predominant pattern across sensors, exponents, and speech rate suggests that the constraint of clarity dominates for lower-frequency words. For medium-frequency words, the smoothness constraint leads to a raising of the trajectory. For the higher-frequency words, both constraints are met simultaneously, resulting in low minima and stronger coarticulation. These consequences of motor practice for articulation challenge both the common view that a higher-frequency of use comes with more articulatory reduction, and cognitive models of speech production positing that articulation is post-lexical.

关键词： coarticulation frequency of use predictability quantile regression generalized additive models

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The naming of orphans in France during World War One: A study of a nationwide cohort of pupilles de la Nation

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HISTORICAL METHODS 2018年第2期51卷 82-91页

作者： Todd, Nicolas Valleron, Alain-Jacques Bougneres, Pierre INSERM U1169 Paris France

The investigation of a simple behavior, child naming, can provide insights into the varying reactions of families confronted by the extraordinary war losses of the First World War. The current study analyses names given in a large cohort of French orphans born 1914-1916, constructed thanks to the linkage of civil registers with a nationwide database of soldiers who died during the War. It shows that a prenatal loss of father was associated with a strong increase in father's name transmission. The phenomenon was twice as intense in officers' offspring. Regression analysis suggests the precise timing of the father's death controlled this change in naming behavior: father's name transmission was at a maximum when the father died at the very beginning of pregnancy.

关键词： World War One bereavement maternal behavior child naming generalized additive models

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Geostatistical models for the Spatial Distribution of Uranium in the Continental United States 13th

Geostatistical Models for the Spatial Distribution of Uraniu...

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13th International Conference on Geocomputation (Geocomputation)

作者： Stoudt, Sara Univ Calif Berkeley 331 Evans Hall Berkeley CA 94704 USA

ISBN: (纸本)9783319227863;9783319227856

Although the United States Geological Survey (USGS) samples geochemical properties across the country, a complete understanding of the distribution of uranium remains elusive. Such an understanding would be useful to many government agencies because uranium can be both harmful to the environment and used to produce nuclear energy. I compare the performance of several nonparametric models for describing the geographic distribution of uranium deposits across the continental United States including the K nearest neighbors method, local regression models, generalized additive models, and Gaussian process models (kriging). I optimize model parameters using cross-validation with a training set and choose the final, most accurate model by comparison of predictions with a test set. I recommend using a kriging model, implemented with lattice krig, and utilizing an optional logarithmic transformation for uranium interpolation. Evidence for successfully avoiding overfitting through this cross-validation process is seen in the applicability of the optimal parameters for the prediction of substances other than uranium.

关键词： Uranium prediction Kriging Local regression generalized additive models

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Early Life Ecology of Tunas in the Gulf of Mexico

Early Life Ecology of Tunas in the Gulf of Mexico

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作者： Cornic, Maelle Marie Texas A&M University

学位级别：Ph.D.

Summer ichthyoplankton surveys were conducted in surface waters of the northern Gulf of Mexico from 2007 to 2010 to characterize distribution and abundance of tuna larvae. The assemblage of tuna larvae was comprised of four genera: Thunnus, Auxis, Euthynnus, and Katsuwonus. True tunas (genus Thunnus) were the most abundant, and four species were detected; Atlantic bluefin tuna (T. thynnus ), yellowfin tuna (T. albacares), bigeye tuna (T. obesus), and blackfin tuna (T. atlanticus ). Intra- and inter-annual variability in distribution and abundance of tuna larvae were observed with higher densities in 2008 and 2009 followed by a decline in abundance in 2010. Principal coordinate analysis (PCoA) and generalized additive models (GAM) based on presence/absence and density were developed to examine the impact of mesoscale features on distribution and abundance on true tuna larvae. Distribution and abundance of true tuna larvae in surface waters were influenced by physicochemical conditions of the water mass, notably sea surface temperature and salinity. Distinct species-specific habitat preferences, were observed and the location of mesoscale oceanographic features influenced larval abundance with higher densities of blackfin tuna, yellowfin tuna, and bigeye tuna associated with convergent zones near the margin of the Loop Current (LC) and other anticyclonic regions (warm core); bluefin tuna was observed in higher densities near cyclonic regions (cold core). Finally, habitat suitability maps were developed based on GAMs and environmental conditions to predict the spatial coverage of suitable habitat of blackfin tuna (2011 and 2015) and yellowfin tuna and bigeye tuna during the Deepwater Horizon oil spill (2010). Habitat suitability maps revealed that the amount of highly suitable habitat of blackfin tuna larvae varied between months (June 6%, July 51%); however, in both months larvae were distributed in similar locations along the continental slope and at the margin of th

关键词： Larvae bluefin tuna yellowfin tuna bigeye tuna blackfin tuna oceanographic features generalized additive models Thesis

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Medium-Term Electricity Demand Forecasting Based on MARS

Medium-Term Electricity Demand Forecasting Based on MARS

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IEEE PES Innovative Smart Grid Technologies Conference Europe (ISGT-Europe)

作者： Ilseven, Engin Gol, Murat Middle East Tech Univ Dept Elect & Elect Engn Ankara Turkey

ISBN: (纸本)9781538619537

The paper proposes use of multivariate adaptive regression splines (MARS) method to perform monthly electricity demand forecasting for medium-term. The model is developed based on specific example of Turkey;however is applicable to any other system. Performance of the proposed method is compared to that of multiple linear regression (MLR), generalized additive model (GAM), and artificial neural networks (ANN) methods. The validation process shows that the proposed model outperforms the other ones by test error and shows stable error performance.

关键词： Multiple Linear Regression generalized additive models Multivariate Adaptive Regression Splines Artificial Neural Networks Electricity Demand Forecasting

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Estimating the spatio-temporal variation of bird phenology using citizen science data

Estimating the spatio-temporal variation of bird phenology u...

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作者： Pedro Guilherme Antunes Lopes da Silva Nicolau Universidade de Lisboa

学位级别：硕士

Migratory bird populations all over Europe are deeply changing. In particular, long-distance migrants are being increasingly affected by climate change and have shown difficulties in adapt- ing to the recent and fast changes. Studying the spatial variation in ecological processes is of fundamental importance when unfolding the mechanisms underlying bird population change. The purpose of this study was understanding the variation in arrival and breeding onset with latitude, estimating the length of time between these two processes and describing their rela- tionship. Using data from two citizen science databases, we estimated the latitudinal variation of arrival date and breeding onset for two migratory bird species, Pied Flycatcher (Ficedula hypoleuca) and Barn Swallow (Hirundo rustica), in Great Britain in the year of 2014. Unlike many of the past site-specific localized studies, here we focused on broad population patterns. generalized additive models were used to produce estimates of both phenological processes, us- ing a spatio-temporal interaction smooth. Arrival was estimated using data from citizen science database, BirdTrack, by modelling the probability of occurrence of each species on complete birding checklists. This allowed the estimation of the date representing arrival of 50% of the population at different locations. For the breeding onset, we used data from citizen science based Nest Record Scheme to model clutch initiation events, as a measure of breeding onset. From this we extracted the date where the estimated peak of breeding occurred at different locations. A ten-folded cross-validation procedure was used to provide metrics of model validation. Both models were bootstrapped to estimate uncertainty, and bootstrap estimates were used to calcu- late the "gap" between arrival and breeding. Our results proved inconclusive for Barn Swallow, yet the Pied Flycatcher showed a marked reduction in gap length with an increase in latitude. This is the first

关键词： phenology generalized additive models bootstrap pied flycatcher barn swallow

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Exploring Topological Effects on Water Distribution System Performance Using Graph Theory and Statistical models

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JOURNAL OF WATER RESOURCES PLANNING AND MANAGEMENT 2017年第1期143卷

作者： Torres, Jacob M. Duenas-Osorio, Leonardo Li, Qilin Yazdani, Alireza Rice Univ Dept Civil & Environm Engn Houston TX 77005 USA Independent Consultancy 267 Country Club Rd Newton MA 02459 USA

Water distribution system (WDS) pipe networks can vary widely in topological layout. The variations in branch and loop combinatorics across large pipe network data sets are ideal for exploring graph-based structural patterns and linkages with engineered performance. To facilitate this exploration, a library of 10,001 lattice-like pipe networks is developed. Each network is equipped with hydraulic, water quality, and diurnal demand information for extended period simulations. Results show strong correlations exist among graph theory metrics (e.g., geodesic, spectral, and combinatorics-based) and performance measures (e.g., maximum hourly unit headloss, average water age, and average chemical concentration). These trends are extended with performance predictions using parametric and semiparametric statistical models. Predictive accuracies are evident for processes that follow diffusion-like behaviors, indicating coupled applications of graph theory and statistical methods may have strong abilities to characterize WDSs at lower computational and analytical costs. Evidence also reveals features from percolation theory, with sharp phase transitions in WDS performance at certain probabilistic thresholds of pipe network connectivity. This may support future probabilistic studies on WDS performance with percolation-like transitions. (C) 2016 American Society of Civil Engineers.

关键词： Water distribution systems Graph theory Network topology Random pipe networks Statistical modeling generalized additive models Percolation theory EPANET

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Nonparametric modeling of clustered customer survival data

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COMMUNICATIONS IN STATISTICS-SIMULATION AND COMPUTATION 2017年第1期46卷 603-618页

作者： Gauran, Iris Ivy M. Barrios, Erniel B. Univ Philippines Diliman Sch Stat Stat BldgMagsaysay Ave Quezon City 1101 Philippines

We incorporate a random clustering effect into the nonparametric version of Cox Proportional Hazards model to characterize clustered survival data. The simulation studies provide evidence that clustered survival data can be better characterized through a nonparametric model. Predictive accuracy of the nonparametric model is affected by number of clusters and distribution of the random component accounting for clustering effect. As the functional form of the covariate departs from linearity, the nonparametric model is becoming more advantageous over the parametric counterpart. Finally, nonparametric is better than parametric model when data are highly heterogenous and/or there is misspecification error.

关键词： Backfitting algorithm Clustered data generalized additive models Nonparametric regression Random effects Survival analysis

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Nonparametric hypothesis testing in clustered survival model

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COMMUNICATIONS IN STATISTICS-SIMULATION AND COMPUTATION 2017年第9期46卷 7485-7500页

作者： Eustaquio, John de Guzman Barrios, Erniel B. Univ Philippines Diliman Sch Stat Sch Stat BldgMagsaysay Ave Quezon City 1101 Philippines

A nonparametric test for the presence of clustering in survival data is proposed. Assuming a model that incorporates the clustering effect into the Cox Proportional Hazards model, simulation studies indicate that the procedure is correctly sized and powerful in a reasonably wide range of scenarios. The test for the presence of clustering over time is also robust to model misspecification. With large number of clusters, the test is powerful even if the data is highly heterogeneous.

关键词： Bootstrap confidence interval Backfitting algorithm Clustered data Survival analysis generalized additive models

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Modelling location, scale and shape parameters of the birnbaumsaunders generalized t distribution

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Journal of Data Science 2017年第2期15卷 221-237页

作者： Luiz R. Nakamura Robert A. Rigby Dimitrios M. Stasinopoulos Roseli A. Leandro Cristian Villegas Rodrigo R. Pescim Departamento de Informatica e Estatstica Universidade Federal de Santa Catarina STORM Research Centre London Metropolitan University Epartamento de Ciências Exatas Escola Superior de Agricultura 'Luiz deQueiroz' Universidade de São Paulo Departamento de Estatstica Universidade Estadual de Londrina

The Birnbaum-Saunders generalized t (BSGT) distribution is a very flflexible family of distributions that admits different degrees of skewness and kurtosis and includes some important special or limiting cases available in the literature, such as the Birnbaum-Saunders and Birnbaum- Saunders t distributions. In this paper we provide a regression type model to the BSGT distribution based on the generalized additive models for location, scale and shape (GAMLSS) framework. The resulting model has high flflexibility and therefore a great potential to model the distribution parameters of response variables that present light or heavy tails, i.e. platykurtic or leptokurtic shapes, as functions of explanatory variables. For different parameter settings, some simulations are performed to investigate the behavior of the estimators. The potentiality of the new regression model is illustrated by means of a real motor vehicle insurance data set.

关键词： Finance GAMLSS generalized additive models penalized splines positively skewed data

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