Outdoor portrait of Ellen Bernkopf nee Catzenstein with her husband Hans Bernkopf; Paris, France. Portraits Couples

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Brother of Lola Gruenthal in Nice, France Portraits Men

Brother of Lola Gruenthal

Portrait of Ya'akov Meir [Jacob Meyer], Head of the Rabbinical Court and President of the Consistorium of the Community of Strasbourg; France.

Caption: J. Meyer, Grand-Rabbin et President du Consistoire Israelite du Department du Bas-Rhin a Strasbourg; also translated in Hebrew

Hans Albert Einstein; Sete, France Portraits; Men

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Boy Scouts Camping

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Boy Scouts Camping

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Hanukkah lamp from France Coin

Obverse: 25 Lirot coin. Reverse: Hanukkah lamp from France

Hanukkah lamp from France Coin

Obverse: 25 Lirot coin. Reverse: Hanukkah lamp from France, 14th century

Scouts, Promoters, and Connectors: The Roles of Ratings in Nearest-Neighbor Collaborative Filtering

Recommender systems aggregate individual user ratings into predictions of products or services that might interest visitors. The quality of this aggregation process crucially affects the user experience and hence the effectiveness of recommenders in e-commerce. We present a characterization of nearest-neighbor collaborative filtering that allows us to disaggregate global recommender performance measures into contributions made by each individual rating. In particular, we formulate three roles-scouts, promoters, and connectors-that capture how users receive recommendations, how items get recommended, and how ratings of these two types are themselves connected, respectively. These roles find direct uses in improving recommendations for users, in better targeting of items and, most importantly, in helping monitor the health of the system as a whole. For instance, they can be used to track the evolution of neighborhoods, to identify rating subspaces that do not contribute ( or contribute negatively) to system performance, to enumerate users who are in danger of leaving, and to assess the susceptibility of the system to attacks such as shilling. We argue that the three rating roles presented here provide broad primitives to manage a recommender system and its community.

Financing And Cooperation For Sustainable Development In The Mediterranean, Sophia Antipolis, France, 3-4 June 2004: Volume II: Technical Report of the Workshop

(263 page document)

The wanderings of a social type in eighteenth-century England and France

Eguíluz, Federico; Merino, Raquel; Olsen, Vickie; Pajares, Eterio; Santamaría, José Miguel (eds.)

Les jeunes face au marché du travail en France: entre difficultés d´insertion et stratégies de pénétration

En une génération, entre 1975 et 1995, le paysage du marché du travail auquel les jeunes font face a radicalement changé.