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Mathematical and Computational Models in Tumor Immunology

F. Pappalardo, A. Palladini, M. Pennisi, F. Castiglione, S. Motta (2012)

Mathematical Modelling of Natural Phenomena

The immune system is able to protect the host from tumor onset, and immune deficiencies are accompanied by an increased risk of cancer. Immunology is one of the fields in biology where the role of computational and mathematical modeling and analysis were recognized the earliest, beginning from 60s of the last century. We introduce the two most common methods in simulating the competition among the immune system, cancers and tumor immunology strategies:...

Measuring association via lack of co-monotonicity: the LOC index and a problem of educational assessment

Danang Teguh Qoyyimi, Ricardas Zitikis (2015)

Dependence Modeling

Measuring association, or the lack of it, between variables plays an important role in a variety of research areas, including education,which is of our primary interest in this paper. Given, for example, student marks on several study subjects, we may for a number of reasons be interested in measuring the lack of comonotonicity (LOC) between the marks, which rarely follow monotone, let alone linear, patterns. For this purpose, in this paperwe explore a novel approach based on a LOCindex,which is...

Meta-analysis techniques applied in prevalence rate estimation

João Paulo Martins, Miguel Felgueiras, Rui Santos (2013)

Discussiones Mathematicae Probability and Statistics

In some cases, the estimators obtained in compound tests have better features than the traditional ones, obtained from individual tests, cf. Sobel and Elashoff (1975), Garner et al. (1989) and Loyer (1983). The bias, the efficiency and the robustness of these estimators are investigated in several papers, e.g. Chen and Swallow (1990), Hung and Swallow (1999) and Lancaster and Keller-McNulty (1998). Thus, the use of estimators based on compound tests not only allows a substantial saving of...

Méthodes d'étude de l'adéquation au modèle logistique à un paramètre (modèle de Rasch)

André Flieller (1994)

Mathématiques et Sciences Humaines

Le modèle de Rasch, ou modèle logistique de réponse à l'item à un paramètre, constitue une avancée méthodologique importante, mais l'étude de l'adéquation de données empiriques à ce modèle ne va pas sans problème. Après une brève présentation du modèle de Rasch, l'article discute certains problèmes généraux rencontrés dans les études d'adéquation. Vingt-quatre tests d'adéquation, graphiques et statistiques sont ensuite présentés et évalués. La nécessité d'employer plusieurs méthodes d'évaluation...

Model selection for quantum homodyne tomography

Jonas Kahn (2009)

ESAIM: Probability and Statistics

This paper deals with a non-parametric problem coming from physics, namely quantum tomography. That consists in determining the quantum state of a mode of light through a homodyne measurement. We apply several model selection procedures: penalized projection estimators, where we may use pattern functions or wavelets, and penalized maximum likelihood estimators. In all these cases, we get oracle inequalities. In the former we also have a polynomial rate of convergence for the non-parametric problem....

Modèles dyadiques en sociométrie

J.-L. Peaucelle (1974)

Mathématiques et Sciences Humaines

L'auteur propose une nouvelle méthode d'exploitation des tests sociométriques de Moreno par ajustement des résultats observés à des modèles de choix aléatoires (tests dichotomiques à expansivité libre). Alors que le modèle aléatoire de Bronfenbrenner s'inscrivait dans un raisonnement destiné à montrer que l'homme ne choisit pas au hasard, l'auteur montre que si on tient compte du caractère dyadique des attractions et de l'hétérogénéité des groupes, on peut représenter les choix par des modèles stochastiques...

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