Maximum Likelihood Approach to Vote Aggregation with Variable Probabilities

Condorcet (1785) initiated the statistical approach to vote aggregation. Two centuries later, Young (1988) showed that a correct application of the maximum likelihood principle leads to the selection of rankings called Kemeny orders, which have the minimal total number of disagreements with those of the voters. The Condorcet-Kemeny-Yoiung approach is based on the assumption that the voters have the same probability of comparing correctly two alternatives and that this probability is the same for any pair of alternatives. We relax the second part of this assumption by letting the probability of comparing correctly two alternatives be increasing with the distance between two alternatives in the allegedly true ranking. This leads to a rule in which the majority in favor of one alternative against another one is given a larger weight the larger the distance between the two alternatives in the true ranking, i.e. the larger the probability that the voters compare them correctly. This rule is not Condorcet consistent. Thus, it may be different from the Kemeny rule. Yet, it is anonymous, neutral, and paretian. However, contrary to the Kemeny rule, it does not satisfy Young and Levenglick (1978)'s local independence of irrelevant alternatives. Condorcet also hinted that the Condorcet winner or the top alternative in the Condorcet ranking is not necessarily most likely to be the best. Young confirms that indeed with a constant probability close to 1/2, this alternative is the Borda winner while it is the alternative whose smallest majority is the largest when the probability is close to 1. We extend his analysis to the case of variable probabilities. Young's result implies that the Kemeny rule does not necessarily select the alternative most likely to be the best. A natural question that comes to mind is whether the rule obtained with variable probabilities does better than the Kemeny rule in this respect. It appears that this performance imporves with the rate at which the probability increases.Vote Aggregation, Kemeny Rule, Maximum Likelihood, Variable Probabilities

The creation of an Islamic stock market index on the Moroccan financial place according to the S&P method

This article aims to broaden the literature on the subject of the construction of Islamic stock market indices by studying the case of Morocco. The results show that the selection process has resulted in a well-diversified universe of Shariha-compliant actions. Moreover, we found 57 of 75 listed companies compliant for the first screening and subsequently, we found 18 compliant companies after reviewing the consolidated balance sheet and The income and expense accounts of these companies. During the analysis period considered (January 2017 to December 2018). The Moroccan All Shares Index (MASI) has been statistically found to have a higher variance than its counterpart the Standard and Poor Moroccan Islamic Index (SPMII), indicating that investors will not make sacrifices for a classic index that has a high level of risk

Inheritance of Time of Flowering and Maturity and their Association with Other Agronomic Characters in Soybean (Glycine Max. (L.) Merrill)

Agronom

The conducted immunity of SPI EEPROM memories

International audienceThis paper focus on the conducted immunity measurement of non-volatile memories up to 1 GHz. A specific measurement flow is introduced, which makes possible to compare the EMC performances in different test cases. Trough measurements and simulation, this study gives a real view on the immunity difference of this integrated circuits (IC)

Cardiomyopathie du péripartum

La cardiomyopathie du péri-partum (CMP-PP) ou syndrome de Meadows, est une cardiomyopathie dilatée survenue pendant ou au décours d'une grossesse, définie par une insuffisance cardiaque avec une fraction d'éjection systolique du ventricule gauche inférieure à 45%. Il s'agit d'une entité pathologique rare dont le mécanisme physiopathologique en cause reste mal élucidé. Sur le plan clinique il s'agit d'une insuffisance cardiaque inopinée d'installation rapide, d'évolution imprévisible avec risque de choc cardiogénique réfractaire justifiant une prise en charge en réanimation cardiovasculaire. La CMP-PP ne nécessite aucun traitement spécifique par rapport aux autres causes d'insuffisance cardiaque. Nous rapportons le cas d'une primigeste de 29 ans qui a consulté à 32 semaines d'aménorrhée dans un tableau d'insuffisance cardiaque congestive en rapport avec une cardiomyopathie du péri-partum. L'objectif de ce travail est de préciser les caractéristiques de cette cardiopathie, qui malgré son caractère exceptionnel ne doit pas être méconnu par l'obstétricien

Minimally invasive and full sternotomy in aortic valve replacement: a comparative early operative outcomes

Introduction: aortic valve replacement is usually performed through a median full sternotomy (MFS) in our department. Minimally invasive aortic valve replacement (MIAVR) has been recently adopted as a new approach. According to the literature, the superiority of MIAVR is controversial. In this study we report early post-operative outcomes in MIAVR compared with MFS access with reference to blood Loss, wound infections, post-operative recovery, morbidity and mortality. Methods: this study was a prospective data collection from 36 consecutive patients undergoing isolated valve replacement. Two population study was identified, MIAVR group (group I n=18) and MFS group (group II n=18). Patients´ data were collected and analyzed using IBM SPSS statistics 21 software and Khi2 test has been used to compare the variables. The study variables are presented as numbers, percentage, median with interquartile range. Pre-operative planning was performed so that to obtain similar characteristics. Results: in group I, upper mini-sternotomy was used in 12 patients and right mini-thoracotomy in 6 patients. There was no difference in term of mortality and morbidity. MIAVR was associated with longer CPB time (93.25 (58-161) vs 131 (75-215) mins, P=0.047) with no significant difference in term of ACC time (81 (33-162) vs 58.8 (59-102) mins P=0.158). MIAVR´ Patients had likely lower incidence of red blood cells transfusion (16.7 vs 52.3%) without significant difference about post-operative haemoglobin (P = 0,330). Patients in group I had shorter ventilation time (2.35 (1-12) vs 9.3 (1-48) hours P < 0.01), shorter ICU stay (2.44 (1-8) vs 4.25 (1-9) days, P = 0,024). The length of hospital stay was shorter, 6.5 (5-9) days in group I vs 7.4 (6-11), P=0.0274. Length of chest tube stay was shorter in group I (mean 1.53 vs 2.4 days, P=0,033). Wound infections were not found in both groups. Conclusion: minimally invasive aortic valve replacement is associated with less blood loss, faster post-operative recovery faster post-operative recovery but increase operation time

Kron Simulation of Field-to-line Coupling Using a Meshed and a Modified Taylor Cell

International audiencePrinted Circuit Board (PCB) traces play a role in the immunity of electronic products. Contrary to Integrated Circuits (ICs), the layout of PCB traces can be changed rather late in a product's design. Therefore, it is interesting to equip the PCB designer with simple tools that predict the immunity of his PCB traces. In this article, we compare two simulations of field-to-long line coupling based on Taylor's model. Firstly, the line is meshed into electrically short Taylor cells and numerically simulated using Kron's method. Secondly, we use one modified Taylor cell, which does not need meshing and is a closed-form, analytical result. The two simulations turn out to be equally precise on a straight microstrip line, the meshed simulation being more flexible, the simulation using a modified Taylor cell being faster

L’hypermédia Géo-terrain : un outil pertinent au service des apprentissages en géologie de terrain

Conscient de l’apport des nouvelles technologies de l’information et de la communication dans l’amélioration de l’enseignement et l’apprentissage, le ministère de l’Éducation nationale marocain a insisté, dans la Charte nationale d’éducation et de formation, sur leur utilisation. Étant donné l’évolution rapide des technologies, il y a une remise en question des modes de transmission, d’acquisition et de restitution des savoirs qui entraîne non seulement des changements dans la sélection et l’articulation des objectifs ainsi que dans les contenus d’apprentissage, mais également une réflexion sur la manière de concevoir et de mettre en oeuvre les situations d’enseignement-apprentissage. Dans ce sens, l’enseignant des sciences de la Terre, qui se base en premier lieu sur le réel naturel, utilise des documents substituts qui rapprochent cette réalité de l’apprenant, et ce, à travers les représentations graphiques, iconiques, les moyens audiovisuels, etc. C’est dans cette perspective que le logiciel Géo-terrain est conçu, pour essayer de combler un vide largement ressenti dans nos établissements.Conscious of the contributions of the new information and communication technologies to improve teaching and learning, the Moroccan Ministry of Education insisted, through the educational and training national charter, on their use. Given the fast evolution of these technologies, “the school” has to question the modes of transmission, acquisition and restoration of knowledge. This entails not only changes in the selection and linkage of the objectives as well as in the contents of learning, but also a reflection on the way of conceiving and implementing education teaching. The teacher in sciences is based first of all on the natural real, he can use documents, which substitute this reality and approach the learner through graphics, iconic representations and audiovisual means, and it is in this perspective that the software Géo-terrain is built

Libéralisation du marché de la Téléphonie mobile au Maroc

Le secteur des télécommunications a connu à travers le monde une grande mutation à partir de la fin du XXe siècle. L’évolution rapide des technologies a donné lieu à une réforme institutionnelle et réglementaire qui a substitué des marchés concurrentiels à des monopoles publics.L’objectif de cet article est de présenter l’expérience marocaine depuis la promulgation de la Loi N° 24-96 et le début de la libéralisation du secteur des télécommunications. Après un bref historique des télécommunications au Maroc, on présente les principales étapes de la libéralisation du secteur de la téléphonie mobile qui a évolué d’un monopole étatique vers un marché concurrentiel à trois opérateurs.On présente ensuite les principaux leviers de régulation qui ont été utilisés par l’Agence Nationale de Réglementation des Télécommunications (ANRT), dont la portabilité des numéros, les tarifs de terminaison d’appels et le partage d’infrastructure. On termine par une évaluation des effets de ces leviers et par une interrogation sur l’évolution du secteur dans la perspective de la promulgation de la Loi N° 121-12