Gauss-Seidel Estimation of Generalized Linear Mixed Models with Application to Poisson Modeling of Spatially Varying Disease Rates

Generalized linear mixed models (GLMMs) provide an elegant framework for the analysis of correlated data. Due to the non-closed form of the likelihood, GLMMs are often fit by computational procedures like penalized quasi-likelihood (PQL). Special cases of these models are generalized linear models (GLMs), which are often fit using algorithms like iterative weighted least squares (IWLS). High computational costs and memory space constraints often make it difficult to apply these iterative procedures to data sets with very large number of cases. This paper proposes a computationally efficient strategy based on the Gauss-Seidel algorithm that iteratively fits sub-models of the GLMM to subsetted versions of the data. Additional gains in efficiency are achieved for Poisson models, commonly used in disease mapping problems, because of their special collapsibility property which allows data reduction through summaries. Convergence of the proposed iterative procedure is guaranteed for canonical link functions. The strategy is applied to investigate the relationship between ischemic heart disease, socioeconomic status and age/gender category in New South Wales, Australia, based on outcome data consisting of approximately 33 million records. A simulation study demonstrates the algorithm's reliability in analyzing a data set with 12 million records for a (non-collapsible) logistic regression model.

Using virtual reality to teach special populations how to cope in crisis: the case of a virtual earthquake

The unique characteristics of special populations such as pre-school children and Down syndrome kids in crisis and their distorted self-image were never studied before, because of the difficulty of crisis reproduction. This study proposes a VR setting that tries to model some special population's behaviour in the time of crises and offers them a training scenario. The sample population consisted of 30 pre-school children and 20 children with Down syndrome. The VR setting involved a high-speed PC, a VPL EyePhone 1, a MR toolkit, a vibrations plate, a motion capture system and other sensors. The system measured and modelled the typical behaviour of these special populations in a Virtual Earthquake scenario with sight and sound and calculated a VR anthropomorphic model that reproduced their behaviour and emotional state. Afterwards one group received an emotionally enhanced VR self-image as feedback for their training, one group received a plain VR self-image and another group received verbal instructions. The findings strongly suggest that the training was a lot more biased by the emotionally enhanced VR self-image than the other approaches. These findings could highlight the special role of the self-image to therapy and training and the interesting role of imagination to emotions, motives and learning. Further studies could be done with various scenarios in order to measure the best-biased behaviour and establish the most natural and affective VR model. This presentation is going to highlight the main findings and some theories behind them.

Deep drilling of glaciers: Russian projects in the Arctic (1975-1995)

The data collection "Deep Drilling of Glaciers: Soviet-Russian projects in Arctic, 1975-1995" was collected by the following basic considerations: - compilation of deep (>100 m) drilling projects on Arctic glaciers, using data of (a) publications; (b) archives of IGRAN; (c) personal communication of project participants; - documentation of parameters, references. Accuracy of data and techniques applied to determine different parameters are not evaluated. The accuracy of some geochemical parameters (up to 1984 and heavy metalls) is uncertain. Most reconstructions of ice core age and of annual layer thickness are discussed; - digitizing of published diagrams (in case, when original numerical data were lost) and subsequent data conversion to equal range series and adjustment to the common units. Therefore, the equal-range series were calculated from original data or converted from digitized chart values as indicated in the metadata. For the methodological purpose, the equal-range series obtained from original and reconstructed data were compared repeatedly; the systematic difference was less then 5-7%. Special attention should be given to the fact, that the data for individual ice core parameters varies, because some parameters were originally measured or registered. Parameters were converted in equal-range series using 2 m steps; - two or more parameter values were determined, then the mean-weighted (i.e. accounting the sample length) value is assigned to the entire interval; - one parameter value was determined, measured or registered independently from the parameter values in depth intervals which over- and underlie it, then the value is assigned to the entire interval; - one parameter value was determined, measured or registered for two adjoining depth intervals, then the specific value is assigned to the depth interval, which represents >75% of sample length ; if each of adjoining depth intervals represents <75% of sample length, then the correspondent parameter value is assigned to both intervals of depth. This collection of ice core data (version 2000) was made available through the EU funded QUEEN project by S.M. Arkhipov, Moscow.

The statuary collection held at the baths of Zeuxippus (Ap 2) and the search for Constantine's museological intentions

Constantino pretendía enseñar al mundo su Constantinopla como la Nueva (la tercera) Troya, el más acabado retrato de la nueva paidea de inspiración griega y romana. Él mismo y su equipo dispusieron de no más que seis años para planear y reconstruir una ciudad entera, la antigua Bizancio; y las artes plásticas, en especial la escultura, ejercieron un rol determinante en todo ese proceso público. Volviendo una vez más la mirada hacia los restos arqueológicos y la descripción literaria de Cristodoro (Antología Griega, libro II) de la colección de estatuas de los Balnearios del Zeuxipo, el presente artículo desenvuelve una lectura museológica de estas estatuas, buscando encuadrarlas en el plan arquitectónico global de Constantino para su nueva capital del Imperio.

The statuary collection held at the baths of Zeuxippus (Ap 2) and the search for Constantine's museological intentions

Constantino pretendía enseñar al mundo su Constantinopla como la Nueva (la tercera) Troya, el más acabado retrato de la nueva paidea de inspiración griega y romana. Él mismo y su equipo dispusieron de no más que seis años para planear y reconstruir una ciudad entera, la antigua Bizancio; y las artes plásticas, en especial la escultura, ejercieron un rol determinante en todo ese proceso público. Volviendo una vez más la mirada hacia los restos arqueológicos y la descripción literaria de Cristodoro (Antología Griega, libro II) de la colección de estatuas de los Balnearios del Zeuxipo, el presente artículo desenvuelve una lectura museológica de estas estatuas, buscando encuadrarlas en el plan arquitectónico global de Constantino para su nueva capital del Imperio.

The statuary collection held at the baths of Zeuxippus (Ap 2) and the search for Constantine's museological intentions

Constantino pretendía enseñar al mundo su Constantinopla como la Nueva (la tercera) Troya, el más acabado retrato de la nueva paidea de inspiración griega y romana. Él mismo y su equipo dispusieron de no más que seis años para planear y reconstruir una ciudad entera, la antigua Bizancio; y las artes plásticas, en especial la escultura, ejercieron un rol determinante en todo ese proceso público. Volviendo una vez más la mirada hacia los restos arqueológicos y la descripción literaria de Cristodoro (Antología Griega, libro II) de la colección de estatuas de los Balnearios del Zeuxipo, el presente artículo desenvuelve una lectura museológica de estas estatuas, buscando encuadrarlas en el plan arquitectónico global de Constantino para su nueva capital del Imperio.

Simulation techniques for design of overhead conductor rail lines for speeds over 140 km/h

In overhead conductor rail lines, aluminium beams are usually mounted with support spacing between 8 and 12 meters, to limit the maximum vertical deflection in the center of the span. This small support spacing limits the use of overhead conductor rail to tunnels, therefore it has been used almost exclusively in metropolitan networks, with operation speeds below 110 km/h. Nevertheless, due to the lower cost of maintenance required for this electrification system, some railway administrations are beginning to install it in some tunnels on long-distance lines, requesting higher operation speeds [1]. Some examples are the Barcelona and Madrid suburban networks (Spain), and recent lines in Turkey and Malaysia. In order to adapt the design of the overhead conductor for higher speeds (V > 160 km/h), particular attention must be paid to the geometry of the conductor rail in critical zones as overlaps, crossings and, especially, transitions between conductor rail and conventional catenary, since the use of overhead conductor rail is limited to tunnels, as already mentioned. This paper describes simulation techniques developed in order to take into account these critical zones. Furthermore, some specific simulations results are presented that have been used to analyze and optimizes the geometry of this special zones to get a better current collection quality, in a real suburban network. This paper presents the work undertaken by the Railways Technology Research Centre (CITEF), having over 10 years of experience in railways research [1-4].

Creation and Validation of the Spanish Durum Wheat Core Collection.

Spanish wheat (Triticum spp.) landraces have a considerable polymorphism, containing many unique alleles, relative to other collections. The existence of a core collection is a favored approach for breeders to efficiently explore novel variation and enhance the use of germplasm. In this study, the Spanish durum wheat (Triticum turgidum L.) core collection (CC) was created using a population structure–based method, grouping accessions by subspecies and allocating the number of genotypes among populations according to the diversity of simple sequence repeat (SSR) markers. The CC of 94 genotypes was established, which accounted for 17% of the accessions in the entire collection. An alternative core collection (CH), with the same number of genotypes per subspecies and maximizing the coverage of SSR alleles, was assembled with the Core Hunter software. The quality of both core collections was compared with a random core collection and evaluated using geographic, agromorphological, and molecular marker data not previously used in the selection of genotypes. Both core collections had a high genetic representativeness, which validated their sampling strategies. Geographic and agromorphological variation, phenotypic correlations, and gliadin alleles of the original collection were more accurately depicted by the CC. Diversity arrays technology (DArT) markers revealed that the CC included genotypes less similar than the CH. Although more SSR alleles were retained by the CH (94%) than by the CC (91%), the results showed that the CC was better than CH for breeding purposes.

Fifth International conference of American states, special handbook for the use of the delegates,

Inserted: Table showing military and naval expenditures of the republics of the American continent, to accompany page 142 of the special handbook for the use of the delegates to the Fifth International conference of American states, prepared by the Pan American union. Washington ... January, 1923. [4] p.

Catalogue of the W. P. Wilstach collection : Memorial Hall.

Mode of access: Internet.

Spanish drama of the golden age; comedia collection.

A catalogue of this collection by José M. Regueiro, titled Spanish drama of the golden age, was published in 1971. Library has at FILM 9845 GUIDE MICRO.