Learning to rank user intent

Personalized retrieval models aim at capturing user interests to provide personalized results that are tailored to the respective information needs. User interests are however widely spread, subject to change, and cannot always be captured well, thus rendering the deployment of personalized models challenging. We take a different approach and study ranking models for user intent. We exploit user feedback in terms of click data to cluster ranking models for historic queries according to user behavior and intent. Each cluster is finally represented by a single ranking model that captures the contained search interests expressed by users. Once new queries are issued, these are mapped to the clustering and the retrieval process diversifies possible intents by combining relevant ranking functions. Empirical evidence shows that our approach significantly outperforms baseline approaches on a large corporate query log

Filial cannibalism in the Black Stork (Ciconia nigra)

AbstractFilial and sibling cannibalism have never been documented in Black Storks (Ciconia nigra). We gathered information on 34 breeding events in 10 Black Stork nests from Estonia (three nests), Hungary (two nests), Poland (two nests) and Spain (three nests) being monitored with camera surveillance, live streaming webcams or intensive monitoring control of nests. Overall, we recorded 16 cases of filial infanticide and two cases where the nestlings died by natural causes and were later cannibalized by either their siblings or their parents. Four nestlings were killed by their parents without any attempt of cannibalism. In the remaining 12 cases of infanticide (66.7% of the total losses), 8 nestlings were consumed by one of the parents while in 4 cases the parents were not able to swallow the previously killed nestlings. All victimised nestlings were the youngest, weakest or smallest in their brood. Eight of 14 cases were identified as being associated with environmental stress or an exceptional matter during the breeding season. In at least five cases, one of the mates was new to the nest. Females committing filial infanticide swallowed or tried to swallow the chicks in five out of nine episodes where the parent’s sex was known