Global ETD Search

171	Les modèles de régression dynamique et leurs applications en analyse de survie et fiabilité / Dynamic regression models and their applications in survival and reliability analysis Tran, Xuan Quang 26 September 2014 (has links) Cette thèse a été conçu pour explorer les modèles dynamiques de régression, d’évaluer les inférences statistiques pour l’analyse des données de survie et de fiabilité. Ces modèles de régression dynamiques que nous avons considérés, y compris le modèle des hasards proportionnels paramétriques et celui de la vie accélérée avec les variables qui peut-être dépendent du temps. Nous avons discuté des problèmes suivants dans cette thèse.Nous avons présenté tout d’abord une statistique de test du chi-deux généraliséeY2nquiest adaptative pour les données de survie et fiabilité en présence de trois cas, complètes,censurées à droite et censurées à droite avec les covariables. Nous avons présenté en détailla forme pratique deY2nstatistique en analyse des données de survie. Ensuite, nous avons considéré deux modèles paramétriques très flexibles, d’évaluer les significations statistiques pour ces modèles proposées en utilisantY2nstatistique. Ces modèles incluent du modèle de vie accélérés (AFT) et celui de hasards proportionnels (PH) basés sur la distribution de Hypertabastic. Ces deux modèles sont proposés pour étudier la distribution de l’analyse de la duré de survie en comparaison avec d’autre modèles paramétriques. Nous avons validé ces modèles paramétriques en utilisantY2n. Les études de simulation ont été conçus.Dans le dernier chapitre, nous avons proposé les applications de ces modèles paramétriques à trois données de bio-médicale. Le premier a été fait les données étendues des temps de rémission des patients de leucémie aiguë qui ont été proposées par Freireich et al. sur la comparaison de deux groupes de traitement avec des informations supplémentaires sur les log du blanc du nombre de globules. Elle a montré que le modèle Hypertabastic AFT est un modèle précis pour ces données. Le second a été fait sur l’étude de tumeur cérébrale avec les patients de gliome malin, ont été proposées par Sauerbrei & Schumacher. Elle a montré que le meilleur modèle est Hypertabastic PH à l’ajout de cinq variables de signification. La troisième demande a été faite sur les données de Semenova & Bitukov, à concernant les patients de myélome multiple. Nous n’avons pas proposé un modèle exactement pour ces données. En raison de cela était les intersections de temps de survie.Par conséquent, nous vous conseillons d’utiliser un autre modèle dynamique que le modèle de la Simple Cross-Effect à installer ces données. / This thesis was designed to explore the dynamic regression models, assessing the sta-tistical inference for the survival and reliability data analysis. These dynamic regressionmodels that we have been considered including the parametric proportional hazards andaccelerated failure time models contain the possibly time-dependent covariates. We dis-cussed the following problems in this thesis.At first, we presented a generalized chi-squared test statisticsY2nthat is a convenient tofit the survival and reliability data analysis in presence of three cases: complete, censoredand censored with covariates. We described in detail the theory and the mechanism to usedofY2ntest statistic in the survival and reliability data analysis. Next, we considered theflexible parametric models, evaluating the statistical significance of them by usingY2nandlog-likelihood test statistics. These parametric models include the accelerated failure time(AFT) and a proportional hazards (PH) models based on the Hypertabastic distribution.These two models are proposed to investigate the distribution of the survival and reliabilitydata in comparison with some other parametric models. The simulation studies were de-signed, to demonstrate the asymptotically normally distributed of the maximum likelihood estimators of Hypertabastic’s parameter, to validate of the asymptotically property of Y2n test statistic for Hypertabastic distribution when the right censoring probability equal 0% and 20%.n the last chapter, we applied those two parametric models above to three scenes ofthe real-life data. The first one was done the data set given by Freireich et al. on thecomparison of two treatment groups with additional information about log white blood cellcount, to test the ability of a therapy to prolong the remission times of the acute leukemiapatients. It showed that Hypertabastic AFT model is an accurate model for this dataset.The second one was done on the brain tumour study with malignant glioma patients, givenby Sauerbrei & Schumacher. It showed that the best model is Hypertabastic PH onadding five significance covariates. The third application was done on the data set given by Semenova & Bitukov on the survival times of the multiple myeloma patients. We did not propose an exactly model for this dataset. Because of that was an existing oneintersection of survival times. We, therefore, suggest fitting other dynamic model as SimpleCross-Effect model for this dataset. Analyse de survie Covariables Modèle de Cox Modèle des hasards proportionnels Modèles de survie de Hypertabastic Modèles des paramétriques flexibles Modèle de régression dynamique Modèle de vie accélérée Cancer de leucémie Cancer de gliome malin Cancer de myélome multiple Test d’ajustement Accelerated Failure Time model Covariates Cox model Dynamic regression models Flexible parametric models Generalized Chi-squared statistic Goodness-of-fit tests Hypertabastic survival models Leukemia cancer Malignant glioma cance Multiple Myeloma cancer Proportional Hazards models Survival data analysis
172	Managing Intellectual Property and Licensing: A Study on Cooperative Research Centres Sheen, Peter Bernard January 2005 (has links) This thesis examines the perceived importance by two-tiered management of Cooperative Research Centres (CRCs) for managing a range of intellectual property issues. Fifty survey items are presented to the executive directors and commercialization managers of 62 CRCs. The survey items are categorized under four themes: relationships with collaborators, project management; design and implementation of agreements; and specific licensing issues. An analysis of the data, using a series of independent samples t-tests, repeated measures t-tests, chi-square tests for independence or relatedness and goodness of fit, shows a range of results. There are significant differences between executive directors and commercialization managers on a number of issues. There are particular emphases or trends about certain issues for the whole sample of managers. These findings are compared with text analyses of 23 CRC strategic planning documents. This is done in order to explore any similarity, difference or nuance between what the managers say in response to the survey items, compared with what is stated in the codified policies of the CRCs. While there is a high degree of consistency among certain themes between the two sets of findings, the overall analysis points to the need for the CRCs to have a better understanding and practice of commercialization opportunities, especially through the involvement of third party commercial interests. It is argued that accommodating third party commercialization interests involves the application of an important knowledge economy principle that has an important bearing on the future economic viability and competitiveness of the CRCs. Chief executive officer Chi-square test for goodness of fit Collaboration Commercializable intellectual assets Commercialization Commercialization manager Competitive advantage Cooperation Cooperative Research Centres Executive directors Human capital Independent samples t-test Intangible assets Internet Innovation Intellectual property Issues Know-how Knowledge economy Knowledge management Licensing Managers Managerial know-how Mann-Whitney test Patenting Project Management Relationships Repeated measures t-test Research and development Supporting intellectual assets Text analysis Third party licensing
173	Extremes of log-correlated random fields and the Riemann zeta function, and some asymptotic results for various estimators in statistics Ouimet, Frédéric 05 1900 (has links) No description available. extreme value theory Gaussian free field branching random walk inhomogeneous environment Riemann zeta function Gibbs measure Ghirlanda-Guerra identities ultrametricity large deviations asymptotic statistics complete monotonicity multinomial probabilities Bernstein estimators uniform law of large numbers Laplace distribution goodness-of-fit tests théorie des valeurs extrêmes champ libre gaussien marche aléatoire branchante environnements inhomogènes fonction zêta de Riemann mesure de Gibbs identités de Ghirlanda-Guerra ultramétricité grandes déviations statistique asymptotique monotonicité complète probabilités multinomiales estimateurs de Bernstein loi uniforme des grands nombres loi de Laplace tests d'ajustements probability probabilité statistics statistique champs log-corrélés log-correlated fields mathematics mathématiques Gaussian fields champs gaussiens
174	The "Equalizer" Administration: Managerial Strategies in the Public Sector Cavalcanti, Bianor Scelza 08 April 2005 (has links) The purpose of this dissertation is to understand the managerial "action" of public administrators in the management of their organizations within the Brazilian context. The research seeks to understand the relationships between managers and formal management mechanisms by exploring the complementary nature of the effective managerial action in the face of structural deficiencies and flaws, considering the possibility of overcoming the structuralism-subjectivism dichotomy present in the construction of the Theory of Organizations. Initially, the study provides a review of the literature on organizational design. It highlights the "goodness of fit" proposition on strategic choice issues concerning the main organizational variables design and organizational goal attainment. It also calls special attention to the emerging interest of designing theorists on interpretivist approaches to the matter, such that of Karl Weick. A review of the the administrative reforms in Brazil is made from the perspective of the main stream organizational design conceptual framework. It highlights the complex dynamics of a constant search for differentiation and flexibilization subject to patterns of advances and reversals, due to the centrality, strength and pervasiveness of the bureaucratic model. It is concluded that in no single given moment, a public manager and his team, may count on a formal organizational design which attends the"congruency" criteria, devised by organizational design conceptual frameworks, to explain organizational results in different environmental sets. Although this conclusion may explain failure at the public sector, it can not provide understanding on the many instances of significative success attained by government operations in spite of inadequate formal administrative structures. This point calls for a better understanding from the interpretivist approach, on how public administrators, strongly associated with good organizational results, engage into transformative action, in order to superate administrative structures flaws and dysfunctional cultural patterns of conduct, structurally present and constantly reproduced, in vigorous developing countries, such as Brazil. The dissertation transcribes the testimony of four outstanding public administrators, doing a deep incursion in the managerial real world of public administration, as subjectively defined by them and transformed by their engagement into action.Through the thematic version of the Oral History methodology, full segments of the complete interviews are categorized into the thirty two managerial strategies captured which are presented on a recategorized manner under eight main strategies: (1) Interchanging Frames of Reference; (2) Exploring the Formal Limits; (3) Playing the Bureaucracy Game; (4) Inducing the Inclusion of Others (5)Promoting Internal Cohesion; (6) Creating Shields against Transgressions; (7) Overcoming Internal Restrictions; (8) Letting the Structures Blossom. Each one of these eight blocks of strategies presented, deserves further reflexive interpretation by the author, on the light of the interpretivist approach to organizational design. A final effort is made, now on theory building, for improving understanding on the matter. In order to find a significant meaning underlining all the strategies extracted from the "practical consciousness" of the interviewers as revealed in their report, the author resort to a metaphor. This metaphor helps to: (1) better describe and understand a not adequately treated phenomenon, namely, good results under inadequate structural social and organizational conditions; (2) reveal the logic and the meaning underlining all the strategies adopted to generate results under these unfaithful conditions; (3) name, accordingly to the nature of the managerial transformative social action involved, an open ended class of managerial interventions of a pragmatic sort driven by an ethics of results much common to good managers, that is, the concept of "managerial equalization"; and (4) give back to public administrators, represented by the interviewees, to be incorporated in their "discursive consciousness", something the most effective and experienced public managers already have as tacit knowledge built in their "practical consciousness", and so, help the education and development of new talents. / Ph. D. equalizer manager equalizing management unfaithfull structural conditions metaphor discursive cousciousness discourse practical cosciousness tacit knowledge agency intentionality ethics empirical bases improvising equalizing theory building meaning agent desining patrimonialism reflexive interpretation organizing inclusion cohesion transgression corruption clientelism nepotism cognitive maps deponents frames of reference transformative action explanation understanding oral history flexbilization decentralization uniformity conceptual frameworks organizational change goodness of fit organizational results organizational performance differentiation uncertainty Brazil develloping countries administrative reform bureaucratic model centralization organizational design organizational theory interpretivist approach subjectivism funcionalism paradigms cultural patterns reproduction structural flaws public manager public administrator formal management mechanisms Action managerial action public administration and management public sector public policy public programs
175	Statistical Inference Chou, Pei-Hsin 26 June 2008 (has links) In this paper, we will investigate the important properties of three major parts of statistical inference: point estimation, interval estimation and hypothesis testing. For point estimation, we consider the two methods of finding estimators: moment estimators and maximum likelihood estimators, and three methods of evaluating estimators: mean squared error, best unbiased estimators and sufficiency and unbiasedness. For interval estimation, we consider the the general confidence interval, confidence interval in one sample, confidence interval in two samples, sample sizes and finite population correction factors. In hypothesis testing, we consider the theory of testing of hypotheses, testing in one sample, testing in two samples, and the three methods of finding tests: uniformly most powerful test, likelihood ratio test and goodness of fit test. Many examples are used to illustrate their applications. finite population correction factor statistical hypothesis type I error composite hypothesis power Central limit theorem Basu theorem critical value goodness of fit test likelihood ratio test Lehmann-Scheffe theorem complete statistic ancillary statistic P-value type II error Rao-Blackwell theorem simple hypothesis one-sided test two-sided test significance level sufficient statistic alternative hypothesis testing hypothesis null hypothesis rejection region confidence interval confidence level minimum variance unbiased estimator interval estimation uniformly most powerful test Cramer-Rao inequality likelihood function mean square error moment estimator error of estimation point estimation maximum likelihood estimator bias consistent estimator minimal sufficient statistic factorization theorem unbiased estimator statistic most powerful test test statistics Neyman-Pearson lemma decision rule

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