CAPRE: A New Methodology for Product Recommendation Based on Customer Actionability and Profitability

International audienceRecommender systems can apply knowledge discovery techniques to the problem of making product recommendations. This aims to establish a customer loyalty strategy and thus to optimize the customer life time value. In this paper we propose CAPRE, a data-mining based methodology for recommender systems based on the analysis of turnover for customers of specific products. Contrary to classical recommender systems, CAPRE does not aspire to predict a customer's behavior but to influence that behavior. By measuring the actionability and profitability of customers, we have the ability to focus on customers that can afford to spend larger sums of money in the target business. CAPRE aggregates rules to extract characteristic purchasing behaviors, and then analyzes the counter-examples to detect the most actionable and profitable customers. We measure the effectiveness of CAPRE by performing a cross-validation on the MovieLens benchmark. The methodology is applied to over 10,000 individual customers and 100,000 products for the customer relationship management of VM Matériaux company, thus assisting the salespersons' objective to increase the customer value

Semantics-based classification of rule interestingness measures

Assessing rules with interestingness measures is the cornerstone of successful applications of association rule discovery. However, as numerous measures may be found in the literature, choosing the measures to be applied for a given application is a difficult task. In this chapter, the authors present a novel and useful classification of interestingness measures according to three criteria: the subject, the scope, and the nature of the measure. These criteria seem essential to grasp the meaning of the measures, and therefore to help the user to choose the ones (s)he wants to apply. Moreover, the classification allows one to compare the rules to closely related concepts such as similarities, implications, and equivalences. Finally, the classification shows that some interesting combinations of the criteria are not satisfied by any index

Interactive visual exploration of association rules with rule-focusing methodology

International audienceOn account of the enormous amounts of rules that can be produced by data mining algorithms, knowledge post-processing is a difficult stage in an association rule discovery process. In order to find relevant knowledge for decision making, the user (a decision maker specialized in the data studied) needs to rummage through the rules. To assist him/her in this task, we here propose the rule-focusing methodology, an interactive methodology for the visual post-processing of association rules. It allows the user to explore large sets of rules freely by focusing his/her attention on limited subsets. This new approach relies on rule interestingness measures, on a visual representation, and on interactive navigation among the rules. We have implemented the rule-focusing methodology in a prototype system called ARVis. It exploits the user's focus to guide the generation of the rules by means of a specific constraint-based rule-mining algorithm

Une méthodologie de recommandations produits fondée sur l'actionnabilité et l'intérêt économique des clients

National audienceDans un contexte économique difficile, la fidélisation des clients figure au premier rang des préoccupations des entreprises. En effet, selon le Gartner, fidéliser des clients existants coûterait beaucoup moins cher que prospecter de nouveaux clients. Pour y parvenir, les entreprises optimisent la marge et le cycle de vie des clients en développant une relation personnalisée aboutissant à demeilleures recommandations. Dans cet article, nous proposons une méthodologie pour les systèmes de recommandations fondée sur l'analyse des chiffres d'affaires des clients sur des familles de produits. Plus précisément, la méthodologie consiste à extraire des comportements de référence sous la forme de règles d'association et à en évaluer l'intérêt économique et l'actionnabilité. Les recommandations sont réalisées en ciblant les contre-exemples les plus actionnables sur les règles les plus rentables.Notreméthodologie est appliquée sur 12 000 clients et 100 000 produits de VMMatériaux afin d'orienter les commerciaux sur les possibilités d'accroissement de la valeur client

An Overview of Interaction Techniques and 3D Representations for Data Mining

International audienceAn Overview of Interaction Techniques and 3D Representations for Data Minin

Dynamique Passée et Récente et Prévision de L’occupation du Sol: cas du Bassin Versant de la Lobo (Centre – ouest de le Côte d’Ivore)

Le développement agricole et la forte croissance démographique ont contribué à la perte du couvert forestier ivoirien. L’objectif de cette étude est d’analyser l’évolution passée (1986 à 2019) et de prédire (2019 à 2050) l’occupation des sols dans le bassin versant de la Lobo. La classification supervisée par maximum de vraisemblance des images landsat de 1986, 2003 et 2019, couplée à la méthode intensity analysis a été appliquée dans cette étude. Les résultats montrent sur la période de 1986 à 2019 une baisse de la végétation de 4708,82 km2 à 4054,72 km2 au détriment de l’augmentation de la mosaïque des cultures et jachères de 6376,56 km2 à 6925,05 km2. Les plans d’eau et sols nus et bâtis ont également augmenté respectivement de 3,73 km2 et 101,88 km2. Par contre, les aires protégées sont restées inchangées avec une superficie de 1516,13 km2. Les changements des classes d’occupation du sol par intensity analysis ont été lent au premier intervalle de temps (1986-2019) mais s’accéléront au deuxième intervalle de temps (2019 à 2050). La mosaïque des cultures et jachères et la végétation ont connu respectivement des pertes de superficies moins intenses et plus intense, tandis que les autres classes ont gagné intensément de superficies durant le premier intervalle de temps. Pendant le deuxième intervalle de temps, seuls les plans d’eau et la mosaïque des cultures et jachères connaîtront des intensités de gains de superficies moins intenses. Il n’y a pas eu de transition des autres classes vers la végétation et la mosaïque des cultures sur toute la période d’étude (1986 à 2050).               Agricultural development and high demographic growth have contributed to the loss of ivorian forest cover. The objective of this study is to analyse the past (1986 to 2019) and  to predict (2019 to 2050) evolution of land use in the Lobo watershed. Supervised maximum likelihood classification of landsat images from 1986, 2003 and 2019, coupled with intensity analysis was applied in this study. The results show a decrease in vegetation from 4708.82 km2 to 4054.72 km2 over the period 1986 to 2019 at the expense of an increase in the mosaic of crops and fallow land from 6376.56 km2 to 6925.05 km2. Water bodies and bare and built-up land also increased by 3.73 km2and 101.88 km2 respectively. Protected areas, on the other hand, remained unchanged at 1516.13 km2. Changes in land use classes by using intensity of analysis were slow in the first time interval (1986-2019) but will accelerate in the second time interval (2019 to 2050). Crop and fallow mosaic and vegetation experienced less intense and more intense area losses respectively, while the other classes gained area intensively during the first time interval. During the second time interval, only water bodies and the crop-fallow mosaic will experience less intense area gains. There was no transition from the other classes to vegetation and crop mosaic over the entire study period (1986 to 2050)

Modélisation Des Extrêmes Climlatiques De La Région De La Marahoué À Partir D’un Générateur Stochastique De Temps Mono-Site (Weagets)

L’objectif de ce travail est d’analyser et de modéliser les tendances pluviométriques extrêmes à l’horizon 2050 à partir des données pluviométriques journalières de 1980 à 2013. Ces données ont été analysées à l’aide du programme ClimPACT 2 master qui a servi de calcul des indices climatiques. Le modèle WEAGETS a été utilisé pour modéliser ces données hydroclimatiques à l’horizon 2050 à partir de la méthode des chaines de Markov d’ordre 3. Les résultats montrent que la moyenne des cumuls de pluies moyennes mensuels observés est de 103,97 mm et celle estimée est de 100,71 mm soit un déficit de 3,26 mm par rapport à celle observée au cours de la chronique d’étude. La précipitation totale maximale d’un jour pluvieux (Rx1day) observé et généré présente une allure décroissante dans la région avec des coefficients respectifs de -0,37 et -0,25. Au cours des périodes 2014 à 2024, les localités de Zuénoula et de Sinfra seront dominées par des séquences sèches qui seront également observées durant les périodes de 2038 à 2050 dans le Sud et le Centre de la zone d’étude. Les jours consécutivement secs (CDD) vont augmenter dans toute la Marahoué, tandis que les jours consécutivement humides (CWD) vont y baisser progressivement. Ces résultats serviront à la mise en place des stratégies d’adaptation des populations face à ce fléau. The objective of this work is to analyze and model extreme rainfall trends up to 2050 based on daily rainfall data from 1980 to 2013. These data were analysed using the ClimPACT 2 master program which was used to calculate the climate indices. The WEAGETS model was used to model these hydroclimatic data by 2050 using the Markov Chain 3 method. The results show that the average monthly average rainfall accumulation observed is 103.97 mm and the estimated average rainfall is 100.71 mm, representing a deficit of 3.26 mm compared to that observed during the study chronicle. The maximum total precipitation of a rainy day (Rx1day) observed and generated shows a decreasing rate in the region with respective coefficients of -0.37 and -0.25. During the periods 2014 to 2024, the localities of Zuénoula and Sinfra will be dominated by dry sequences which will also be observed during the periods 2038 to 2050 in the southern and central parts of the study area. Consecutively dry days (CDD) will increase throughout Marahoué, while consecutively wet days (CWD) will gradually decrease there. These results will be used to put in place strategies to help populations adapt to this scourge

Cartographie De La Vulnérabilité À La Pollution Des Aquifères Du Socle Précambrien : Cas De La Région D’oumé (Centre-Ouest De La Côte D’ivoire)

Development of agricultural and mining activities and the rapid growth of the population (3.8%) in Oumé’s area, constitute a potential risk of groundwater’s pollutions. This study interested Oumé’s area and aims to elaborate a map of vulnerability to pollution for a better management of groundwaters. The database is constituted by various data in particular, geological, hydrogeological, geomorphological, pluviometric data and satellite image. Methods DRASTIC and GOD were used in this study. Results of DRASTIC method indicated that 31.86% of study area have a very low vulnerability, 68.12% a low vulnerability and 0.02% a moderate vulnerability. With GOD method, 12.8% of study area have a very low vulnerability, 86.46% a low vulnerability and 0.74% a moderate vulnerability. The chemical analysis of groundwater showed that weaker rates of nitrates (0-14mg/l) registered inside the surely well protected zones. These observations have led to validate some various maps obtained. Result of the test of Kappa revealed that coefficient K is reliable and gave moderate agreement (K=0.43) between both methods. This agreement is confirmed by the surface analysis (79.01%). In this study, the DRASTIC method supplied better results and is thus better adapted for the evaluation of vulnerability in the pollution of groundwater of this area

Étude de l’influence de la densité de peuplement sur le fonctionnement du sol dans des chênaies par la mesuredes rapports isotopiques du carbone (13C/12C) et de l’azote (15N/14N) en EA-IRMS

International audienc

Application of a hemodynamic model to epileptic spikes

Despite the interest in simultaneous EEG-fMRI studies of epileptic spikes, the link between epileptic discharges and their corresponding hemodynamic responses is poorly understood. We applied two biophysical models in order to investigate the mechanisms underlying the neurovascular coupling in epilepsy: a metabolic hemodynamic model, and a neural mass model that simulates epileptic discharges. Analyzing the effect of epileptic neuronal activity on the BOLD response we focussed on the issues of linearity and on the origin of negative BOLD signals. In our BOLD simulation results both sub- and supra-linearity occur one after another. The size of these effects depends on the spike frequency, as well as on the amplitude of the excitatory part of the neural input. For the hemodynamic model used in this study, we found that the sign of the BOLD response is mainly determined by the area under the curve describing the excitatory neural activity. Therefore, a strong deactivation following the initial peak of the excitatory time course of an epileptic spike is necessary to obtain a negative BOLD