摘要:
A method and system for rank aggregation of entities based on supervised learning is provided. A rank aggregation system provides an order-based aggregation of rankings of entities by learning weights within an optimization framework for combining the rankings of the entities using labeled training data and the ordering of the individual rankings. The rank aggregation system is provided with multiple rankings of entities. The rank aggregation system is also provided with training data that indicates the relative ranking of pairs of entities. The rank aggregation system then learns weights for each of the ranking sources by attempting to optimize the difference between the relative rankings of pairs of entities using the weights and the relative rankings of pairs of entities of the training data.
摘要:
The present invention provides techniques for generating data that is used for ranking documents. In one embodiment, a method involves the step of extracting data features from a number of documents to be ranked. The data features extracted from the documents are established in conjunction with a first feature map and a second feature map, wherein the first feature map and the second feature map are capable of keeping the relative ordering between two document instances. In one embodiment, the two feature maps are specially a divide feature map and a minus feature map. Once the data is mapped, the method involves the step of generating pairwise preferences from the first feature map and the second feature map. Then the pairwise preferences are aggregated into a total order, which can be used to produce one or more relevancy scores.
摘要:
This disclosure describes various exemplary methods, computer program products, and systems for selecting features for ranking in information retrieval. This disclosure describes calculating importance scores for features, measuring similarity scores between two features, selecting features that maximizes total importance scores of the features and minimizes total similarity scores between the features. Also, the disclosure includes selecting features for ranking that solves an optimization problem. Thus, this disclosure identifies relevant features by removing noisy and redundant features and speeds up a process of model training.
摘要:
Procedures for learning and ranking items in a listwise manner are discussed. A listwise methodology may consider a ranked list, of individual items, as a specific permutation of the items being ranked. In implementations, a listwise loss function may be used in ranking items. A listwise loss function may be a metric which reflects the departure or disorder from an exemplary ranking for one or more sample listwise rankings used in learning. In this manner, the loss function may approximate the exemplary ranking for the plurality of items being ranked.
摘要:
A method and system for generating a ranking function to rank the relevance of documents to a query is provided. The ranking system learns a ranking function from training data that includes queries, resultant documents, and relevance of each document to its query. The ranking system learns a ranking function using the training data by weighting incorrect rankings of relevant documents more heavily than the incorrect rankings of not relevant documents so that more emphasis is placed on correctly ranking relevant documents. The ranking system may also learn a ranking function using the training data by normalizing the contribution of each query to the ranking function so that it is independent of the number of relevant documents of each query.
摘要:
Systems and methods for processing user queries and identifying a set of documents relevant to the user query from a database using multi ranker search are described. In one implementation, the retrieved documents can be paired to form document pairs, or instance pairs, in a variety of combinations. Such instance pairs may have a rank order between them as they all have different ranks. A classifier, hyperplane, and a base ranker may be constructed for identifying the rank order relationships between the two instances in an instance pair. The base ranker may be generated for each rank pair. The systems use a divide and conquer strategy for learning to rank the instance pairs by employing multiple hyperplanes and aggregate the base rankers to form an ensemble of base rankers. Such an ensemble of base rankers can be used to rank the documents or instances.
摘要:
This disclosure describes various exemplary methods, computer program products, and systems for selecting features for ranking in information retrieval. This disclosure describes calculating importance scores for features, measuring similarity scores between two features, selecting features that maximizes total importance scores of the features and minimizes total similarity scores between the features. Also, the disclosure includes selecting features for ranking that solves an optimization problem. Thus, this disclosure identifies relevant features by removing noisy and redundant features and speeds up a process of model training.
摘要:
A method and system for rank aggregation of entities based on supervised learning is provided. A rank aggregation system provides an order-based aggregation of rankings of entities by learning weights within an optimization framework for combining the rankings of the entities using labeled training data and the ordering of the individual rankings. The rank aggregation system is provided with multiple rankings of entities. The rank aggregation system is also provided with training data that indicates the relative ranking of pairs of entities. The rank aggregation system then learns weights for each of the ranking sources by attempting to optimize the difference between the relative rankings of pairs of entities using the weights and the relative rankings of pairs of entities of the training data.
摘要:
Described is a technology in which documents associated with a query are ranked by a ranking model that depends on the query. When a query is processed, a ranking model for the query is selected/determined based upon nearest neighbors to the query in query feature space. In one aspect, the ranking model is trained online, based on a training set obtained from a number of nearest neighbors to the query. In an alternative aspect, ranking models are trained offline using training sets; the query is used to find a most similar training set based on nearest neighbors of the query, with the ranking model that corresponds to the most similar training set being selected for ranking. In another alternative aspect, the ranking models are trained offline, with the nearest neighbor to the query determined and used to select its associated ranking model.
摘要:
The present invention introduces a new approach to learning systems. More specifically, the present invention provides learned methods for optimize ranking models. In one aspect of the present invention, an objective function is defined as the likelihood of ground truth based on a Luce model. In another aspect, techniques of the present invention provide a way of representing different kinds of ground truths as a constraint set of permutations. In yet another aspect of the present invention, techniques of the present invention provide a way of learning the model parameter by maximizing the likelihood of the ground truth.