Sperm whales (Physeter macrocephalus) are nomadic species typically studied across broad (>100km) spatial scales. In this study, I model fine-scale (or submesocale) habitat preferences, determine how organization into distinctive units of associating female and juveniles influences habitat use, and describe how movements change across the 24-hour cycle. This study concerns a well-studied population of sperm whales off Dominica in the Eastern Caribbean. Statistical models suggest that overall habitat use is rather homogenous, and social behaviour is best predicted by the presence of mature males. Variation among social units in the amount of time spent, and space occupied, within the study area indicates habitat preferences at the level of the social unit. Finally, movements are influenced by the diurnal cycle, as whales tend to move from inshore to offshore at dusk. This study betters our understanding of sperm whale habitat decisions over fine-scales, and has implication for conservation and management strategies.

The minimum description length (MDL) principle originated from data compression literature and has been considered for deriving statistical model selection procedures. Most existing methods utilizing the MDL principle focus on models consisting of independent data, particularly in the context of linear regression. The data considered in this thesis are in the form of repeated measurements, and the exploration of MDL principle begins with classical linear mixed-effects models. We distinct two kinds of research focuses: one concerns the population parameters and the other concerns the cluster/subject parameters. When the research interest is on the population level, we propose a class of MDL procedures which incorporate the dependence structure within individual or cluster with data-adaptive penalties and enjoy the advantages of Bayesian information criteria. When the number of covariates is large, the penalty term is adjusted by data-adaptive structure to diminish the under selection issue in BIC and try to mimic the behaviour of AIC. Theoretical justifications are provided from both data compression and statistical perspectives. Extensions to categorical response modelled by generalized estimating equations and functional data modelled by functional principle components are illustrated. When the interest is on the cluster level, we use group LASSO to set up a class of candidate models. Then we derive a MDL criterion for this LASSO technique in a group manner to selection the final model via the tuning parameters. Extensive numerical experiments are conducted to demonstrate the usefulness of the proposed MDL procedures on both population level and cluster level.

The minimum description length (MDL) principle originated from data compression literature and has been considered for deriving statistical model selection procedures. Most existing methods utilizing the MDL principle focus on models consisting of independent data, particularly in the context of linear regression. The data considered in this thesis are in the form of repeated measurements, and the exploration of MDL principle begins with classical linear mixed-effects models. We distinct two kinds of research focuses: one concerns the population parameters and the other concerns the cluster/subject parameters. When the research interest is on the population level, we propose a class of MDL procedures which incorporate the dependence structure within individual or cluster with data-adaptive penalties and enjoy the advantages of Bayesian information criteria. When the number of covariates is large, the penalty term is adjusted by data-adaptive structure to diminish the under selection issue in BIC and try to mimic the behaviour of AIC. Theoretical justifications are provided from both data compression and statistical perspectives. Extensions to categorical response modelled by generalized estimating equations and functional data modelled by functional principle components are illustrated. When the interest is on the cluster level, we use group LASSO to set up a class of candidate models. Then we derive a MDL criterion for this LASSO technique in a group manner to selection the final model via the tuning parameters. Extensive numerical experiments are conducted to demonstrate the usefulness of the proposed MDL procedures on both population level and cluster level.

Masters Research - Master of Medical Science / Numerous overseas studies have linked both short and long-term exposures to outdoor air pollution to a range of health effects. The differences in air pollution sources, climate and geography in Australia challenged the generalisability of these overseas findings to the Australian setting. In response, the Hunter Illawarra Study of Airways and Air Pollution (HISAAP) was undertaken. The aim of Phase II of HISAAP was to assess the short-term effects of particulates on respiratory health amongst symptomatic children. This thesis presents the results of an analysis of the 345 primary school children eligible for Phase II of the Hunter component of HISAAP. There were multiple daily diary measures on each child, different types of outcomes such as continuous, dichotomous and count variables, as well as several sources of exposure data on pollutants. Because of the complex and hierarchical nature of data, there are several possible methods of analyses that could be used. The thesis begins with a description of the sampling methods used in the study. Next, an overview of the literature on the relationship between air pollution and respiratory health, followed by a review of the methods of analyses appropriate for longitudinal diary studies of this nature. The methods and results are then presented for the analyses of the association between the three main outcomes of interest – evening peak flow, day cough and bronchodilator use – and air quality variables: particulates (PM10 and TSP), sulphur dioxide, pollens and fungi, using three modelling approaches. These include a representative of data reduction methods (Aggregate analysis), subject-specific or mixed-model methods (Korn-Whittemore analysis) and marginal methods (Generalised Estimating Equations). All estimates were adjusted for climate-related covariates and trend. The final chapter discusses the advantages and disadvantages of the various methods of analyses, and a recommendation for analytic techniques for further studies.

Αναμφισβήτητα, τις τελευταίες δεκαετίες έχουν λάβει χώρα σημαντικές αλλαγές στο επιχειρησιακό περιβάλλον σε παγκόσμια κλίμακα, οι οποίες έχουν μεταβάλλει ριζικά τη δομή του. Παραδείγματα τέτοιων αλλαγών αποτελούν η εισαγωγή ευέλικτων συστημάτων παραγωγής, η εντατικοποίηση και η αυτοματοποίηση των παραγωγικών διαδικασιών, η αύξηση των γενικών εξόδων τόσο ως ποσό όσο και ως ποσοστό επί του συνολικού κόστους των προϊόντων, η μείωση του κόστους άμεσης εργασίας (κυρίως στη βιομηχανία ) ως ποσοστό του κόστους παραγωγής, η αύξηση της ποικιλίας προϊόντων που παράγονται σε μικρές ποσότητες και με διαφορετικές προδιαγραφές, η αύξηση του ρυθμού εισαγωγής νέων προϊόντων στην αγορά τα οποία έχουν μικρό κύκλο ζωής, η υιοθέτηση πελατοκεντρικού προσανατολισμού κ.α. Οι παραπάνω αλλαγές σε συνδυασμό με την αύξηση της έντασης του ανταγωνισμού και της συνεπακόλουθης μείωσης των περιθωρίων κέρδους, έχουν ανάγει σε πηγή ανταγωνιστικού πλεονεκτήματος την αποτελεσματική παρακολούθηση και, κυρίως, διοίκηση τους κόστους των ξενοδοχειακών επιχειρήσεων. Για τη λήψη ορθών επιχειρηματικών αποφάσεων απαιτείται ορθή πληροφόρηση, η οποία, σε μεγάλο βαθμό, στηρίζεται στα αριθμητικά μεγέθη που παράγει η κοστολογική οργάνωση των ξενοδοχειακών επιχειρήσεων. Εξάλλου, ο σωστός προγραμματισμός και η άσκηση της οικονομικής πολιτικής από το Κράτος απαιτεί επίσης σωστή και αντικειμενική πληροφόρηση, που στηρίζεται τα μέγιστα στα μεγέθη του κόστους. Η Κοστολόγηση είναι, δηλαδή, η διαδικασία που αριθμοποιεί τη ζωή των οικονομικών μονάδων, συγκεντρώνει, αναλύει, επεξεργάζεται, συσχετίζει τα αριθμητικά μεγέθη τα οποία συνοψίζει και παρουσιάζει καταλλήλως ώστε να είναι αξιοποιήσιμα από τους λήπτες των επιχειρηματικών αποφάσεων. Για να είναι όμως τα μεγέθη του κόστους αξιοποιήσιμα θα πρέπει, εκτός των άλλων, να τυγχάνουν μιας τέτοιας επεξεργασίας, κατάταξης και συσχετισμών ώστε να διασφαλίζεται η μέσω αυτών και δι’ αυτών κατάρτιση ορθών οικονομικών εκθέσεων και γενικά η άσκηση ελέγχου για την ορθότητα κάθε επιχειρηματικής απόφασης. Η σημαντικότητα του εργαλείου της κοστολόγησης για την παροχή αξιόπιστων πληροφοριών στη διοίκηση της ξενοδοχειακής επιχείρησης, για τη λήψη αποφάσεων αποτέλεσε έναυσμα για τη διενέργεια της παρούσας μελέτης η οποία αναφέρεται σε ένα από τα πλέον σύγχρονα πεδία έρευνας και ανάπτυξης της Λογιστικής Επιστήμης που συνδέεται με τη χρησιμοποίηση επιστημονικών μεθόδων, αρχών και κανόνων, στη Διοίκηση των επιχειρήσεων και ιδιαίτερα των ξενοδοχειακών. Όπως είναι γνωστό, η διοίκηση των επιχειρήσεων, πραγματοποιείται μέσω των λαμβανόμενων καθημερινά επιχειρηματικών αποφάσεων από τους υπεύθυνους φορείς εξουσίας – αρμοδιότητας και ευθύνης – που βρίσκονται σε όλα τα επίπεδα της Διοικητικής πυραμίδας. Αναλυτικότερα, οι επιμέρους στόχοι της παρούσας μελέτης είναι οι ακόλουθοι: Μέσα από την ανάλυση και την εμπειρική έρευνα των ξενοδοχείων να προκύψει μια πολιτική λογιστικής και κοστολογικής οργάνωσης αυτών, επισήμανση της σημασίας και του μεγέθους της τουριστικής ανάπτυξης της Ελλάδας, αναφορά στον εγχώριο και διεθνή ανταγωνισμό, παρουσίαση της κοστολογικής οργάνωσης των ξενοδοχείων και ανάλυση των κοστολογικών συστημάτων που χρησιμοποιούνται από αυτά, λαμβάνοντας υπόψη τις ιδιαιτερότητες του κλάδου των ξενοδοχειακών επιχειρήσεων που έχουν αντίκτυπο στην κοστολόγηση (τιμολόγηση, εποχικότητα, κόστος αδράνειας- υπολειτουργίας, value added, non value added δαπάνες, κ.λπ.). Η παρούσα διπλωματική μελέτη αποτελείται από οκτώ (8) κεφάλαια στα οποία πραγματεύονται τα ακόλουθα : Στο Κεφάλαιο 1 αναλύεται η δομή του ξενοδοχειακού συστήματος, στο Κεφάλαιο 2 αναλύεται η δομή του Τουριστικού συστήματος, στο Κεφάλαιο 3 αξιολογείται και παρουσιάζεται η οργάνωση του κόστους ως μεταβλητής που στηρίζει απαραιτήτως κάθε επιχειρηματική απόφαση, στο Κεφάλαιο 4 παρουσιάζεται η κοστολογική οργάνωση των ξενοδοχειακών επιχειρήσεων, στο Κεφάλαιο 5 αναλύεται ένα από τα σημαντικότερα είδη Κοστολόγησης, η Κοστολόγηση ανά δραστηριότητα, στο Κεφάλαιο 6 παρουσιάζονται στατιστικά στοιχεία για την χρηματοοικονομική ανάλυση του κλάδου των ξενοδοχειακών μονάδων, στο Κεφάλαιο 7 παρουσιάζεται η κοστολογική ανάλυση του κλάδου και στο Κεφάλαιο 8 παρουσιάζονται τα βασικά συμπεράσματα της μελέτης καθώς και προτάσεις βελτίωσης της εφαρμογής της κοστολόγησης στην εποχή μας. / Undeniably, the last decades have taken place important changes in the operational environment in world scale, that have alter radically his structure. Examples of such changes constitute the import of flexible systems of production, the intensifying and the automation of productive processes, the increase of general expenses so much as sum what as percentage on the total cost of products, the reduction of cost of direct work (mainly in the industry) as percentage of cost of production, the increase of variety of products that is produced in small quantities and with different specifications, the increase of rhythm of import of new products in the market which have small circle of life, the adoption of orientation to the customers, etc. The above changes in combination with the increase of intensity of competition and subsequent reduction of margins of profit, have reduced in source of competitive advantage the effective follow-up and, mainly, their administration of cost of hotel enterprises. For the decision-making equitable enterprising is required equitable information, which, to a great degree, is supported in the numerical sizes that produces the cost estimating organization of hotel enterprises. Moreover, the correct planning and the exercise of economic policy from the State require also correct and objective information that supports biggest in sizes of cost. The cost accounting is, that is to say, the process that puts in a line the life of economic units, assembles, analyzes, processes, connects the numerical sizes which it summarizes and presents suitably so that they are exploitable from the recipients of enterprising decisions. In order to be the sizes of cost exploitable it will be supposed, except the other, that they enjoy a such treatment, classification and correlations so that is ensured via these and of these training of equitable economic reports and in general the exercise of control on the correctness of each enterprising decision. The importance of tool of cost accounting for the benefit of reliable information in the administration of hotel enterprise, for the decision-making constituted spark for the realization of present study which is reported in one of the most modern fields of research and growth of Accountant Science that is connected with the utilization of scientific methods, values and rules, in the Administration of enterprises and particularly of hotels. As it is known, the administration of enterprises, it is realized via the received daily enterprising decisions by the responsible institutions of power- competence and responsibility - that they are found in all levels of Administrative pyramid. More analytically, the individual objectives of present study are the followings: Through the analysis and the empiric research of hotels result a policy accountant and cost estimating organization of these, pointing out of importance and size of tourist growth of Greece, report in the domestic and international competition, presentation of cost estimating organization of hotels and analysis of cost estimating systems that is used by them, taking into consideration his particularities of branch of hotel enterprises that have impact in the cost accounting (pricing, cost of inactivity, value added, non value added expenses, etc.). The present diplomatic study is constituted from eight (8) capitals in which deal with following: In Capital 1 it is analyzed the structure of hotel system, in Capital 2 it is analyzed the structure of Tourist system, in Capital 3 it is evaluated and presents itself the organization of cost as variable that supports essentially each enterprising decision, in Capital 4 it is presented the cost estimating organization of hotel enterprises, in Capital 5 it is analyzed one of the most important types of Cost accounting, the Cost accounting per activity, in Capital 6 they are presented statistical elements for the financing analysis of branch of hotel units, in Capital 7 it is presented the cost estimating analysis of branch and in Capital 8 they are presented the basic conclusions of study as well as proposals of improvement of application of cost accounting in our period of time.

Orientador: João Franscisco Escobedo / Banca: Luiz Roberto Angelocci / Banca: Paulo Ademar Martins Leal / Banca: Roberto Vicente Calheiros / Banca: Augusto José Pereira Filho / Resumo: No presente trabalho é apresentado um modelo de correção anisotrópico para radiação difusa medida com anel de sombreamento Melo-Escobedo (ME) em função do índice de claridade (razão da radiação global pela extraterrestre). São propostos ainda dois modelos estatísticos da fração difusa isotrópica ( ) e anisotrópica ( ) em função do índice de claridade na estimativa das irradiações horária, diária e mensal. A base de dados das radiações global, direta na incidência e difusa medida pelo anel de sombreamento ME utilizada compreende o período de 1996 a 2002 monitorada pelo Laboratório de Radiometria Solar da UNESP/Botucatu/SP. O modelo de correção anisotrópico, obtido a partir das irradiâncias difusa medida pelo anel de sombreamento Melo-Escobedo (raio 40cm e largura 10cm) e medida pelo método da diferença (referência), considerou três intervalos discretos de por meio de três equações: (0 < < 0,30 - nublado); (0,30 < < 0,65 - parcialmente nublado); e (0,65 < < 1 - aberto). O modelo anisotrópico foi validado comparando-se a irradiância difusa anisotrópica estimada com a irradiância difusa de referência numa base de dados independente, mostrando bons resultados conforme os indicativos estatísticos MBE(%) = 0,25%, 0,51% e -0,38% e RMSE(%)= 5,78%, 9,83% e 12,93% para as coberturas de céu nublado, parcialmente nublado e aberto, respectivamente...(Resumo completo, clicar acesso eletrônico abaixo). / Abstract: The present work presents an anisotropic correction model as a function of the clearness index (global/extraterrestrian radiation) for the diffuse radiation measurements with the Melo-Escobedo (ME) shadowring. Two statistical estimate models for the isotropic ( ) and anisotropic ( ) diffuse fraction as a function of clearness index are also proposed to estimate the hourly, daily and monthly diffuse irradiations. The global, diffuse measured by the shadowring ME and the direct radiations measurements were provided by the Laboratory of Solar Radiometry of UNESP/Botucatu/SP in the period from 1996 to 2002. The anisotropic correction model, obtained from the comparison between the diffuse irradiance measured by the Melo-Escobedo shadowring (radius of 40cm and width of 10cm) and the diffuse irradiance measured by the difference method (reference), considered three discreet intervals, with three equations: (0 < <0,30 - cloudy); (0,30 < <0,65 - partially cloudy); and (0,65 < <1 - clear). The anisotropic correction model was validated through the comparison of the anisotropic diffuse irradiance and the reference diffuse irradiance with an independent database, showing good results according to the statistical indicators MBE (%) = 0,25%, 0,51% and -0,38% and RMSE (%) = 5,78%, 9,83% and 12,93% for cloudy, partially cloudy and clear skies, respectively. The anisotropic correction model showed to be dependent of the shadowring dimensions, and for a same radius-width relationship, the smaller radius (20cm) and width (5cm) shadowring needed smaller numeric correction than the larger ray (40cm) and width (10cm) one. The anisotropic correction model was applied in the diffuse irradiance measurements obtained with a 5 minutes frequency automated operating system. The algorithm calculated hourly, daily and monthly anisotropic diffuse irradiations and compared to the ones from the reference diffuse ...(Complete abstract, access undermentioned eletronic address). / Doutor

M.Sc. (Geography) / Please refer to full text to view abstract

The problem of creating dynamic fare model consists of two tasks - estimating demand for train tickets and multistage optimization of price of fare. We introduce a model of inhomogeneous Markov process for the process of selling the tickets in this thesis. Because of the complexity of the state space the optimization problem needs to be solved using simulation methods. The solution was implemented in R language for single-stage and two-stage problems. Before this application we summarize the theory of inhomogeneous Markov process with special attention to process with separable inhomogeneity. Then we propose methods for estimating the intensity using maximum likelihood theory. We also describe and compare two algorithms for simulated optimization. Powered by TCPDF (www.tcpdf.org)

This thesis describes the issue of selecting of the company's clients Fragile media s. r. o. The company looks at the financial benefits and time. The target of this thesis is to determine what kind of clients brings to Fragile media s. r. o. the greatest benefit. This issue I will discuss in the practical part of this thesis by using multi-criteria decision making. In next step I will deal with what effect will have other methods of estimating weights of the criteria for the results.

A economia brasileira passa por um momento positivo em sua história, devido principalmente a fatores gerados pela estabilidade econômica advinda com o Plano Real. O conjunto de dados apresentados neste trabalho evidencia uma melhora das condições socioeconômicas de grande parte da população, o que levou a um aumento da renda dos indivíduos e um fortalecimento do poder de consumo dos brasileiros. Nesse contexto, esta tese teve como objetivo a busca de evidências que indicassem uma mudança e possível sofisticação do padrão de consumo dos domicílios brasileiros. Além disso, procurou-se verificar em quais níveis socioeconômicos e em quais regiões as mudanças do padrão de consumo foram mais significativas. Os dados utilizados neste trabalho derivam de um painel de consumidores (Homescan) e foram analisadas informações de dez categorias de produtos de consumo doméstico para os anos de 2007, 2008 e 2009, considerando-se as áreas geográficas auditadas pela Nielsen e os níveis socioeconômicos dos domicílios. Nas análises dos dados, utilizaram-se modelos de equações de estimação generalizadas (EEG), além de análises estatísticas descritivas para avaliar a evolução das variáveis não-contempladas nesses modelos. Além disso, utilizaram-se dados de outra pesquisa (Retail Index) para complementar os resultados obtidos com o painel de consumidores. Os resultados das análises realizadas indicam uma mudança do padrão de consumo, primordialmente, nos domicílios de nível socioeconômico médio (classe C) e baixo (classes D e E) no período analisado. Quanto às áreas geográficas pesquisadas, os destaques foram o Nordeste, o grande Rio de Janeiro e a região Sul. Levando-se em consideração que as categorias analisadas são produtos mais elaborados e de maior valor agregado, o aumento do consumo da grande maioria das categorias nesses níveis socioeconômicos evidencia uma sofisticação do consumo desses domicílios. Esse ambiente de sofisticação dos padrões de consumo, principalmente das classes de renda média e baixa, exigirá das empresas que atuam no mercado de bens e serviços novas estratégias para atender as demandas de consumidores mais conscientes e exigentes. Assim, o grande desafio dessas empresas será decifrar o caminho da expansão e diversificação da cesta de compra desses consumidores. / The Brazilian economy is currently going through a positive time in its history, mainly as a result of factors generated by the economic stability conferred by the Plano Real financial plan. The data presented in this work shows an improvement in the socioeconomic conditions of the vast majority of the population, which has led to an increase in income for individuals, and a strengthening of the consumer power of Brazilians. In this context, this thesis looks for evidence that indicates a change and possible sophistication of consumer patterns in Brazilian households. It also seeks to determine the socioeconomic levels, and the regions in which the changes in consumer patterns are most significant. The data used in this work are derived from a panel of consumers (Homescan), and information from ten categories of domestic consumer goods were analyzed for the years 2007, 2008 and 2009, considering the geographic areas audited by Nielsen and the socioeconomic levels of the households. In the data analyses, generalized estimating equation (GEE) models are used, as well as descriptive statistical analyses, to evaluate the evolution of variables not included in these models. Data are also used from another survey (Retail Index), to complement the results obtained with the panel of consumers. The results of the analyses indicate a change in consumer patterns, particularly in households belonging to the middle (class C) and low (classes D and E) socioeconomic classes, for the period analyzed. In terms of geographical areas researched, the areas highlighted were the Northeast, the greater Rio de Janeiro and the South region. Taking into consideration that the categories analyzed consist of more elaborate products, with higher added value, the increased consumption for the majority of categories at these socioeconomic levels shows that consumption in these households has become more sophisticated. This environment of increasing sophistication of consumer patterns, particularly among the middle and low income classes, will require companies in the goods and services market to implement strategies to meet the requirements of these more aware and demanding consumers. Therefore, the greatest challenge for these companies is to seize the expansion and diversification path of the shopping basket for these consumers.