摘要:
An improved system and method is provided for feature selection for text classification using subspace sampling. A text classifier generator may be provided for selecting a small set of features using subspace sampling from the corpus of training data to train a text classifier for using the small set of features for classification of texts. To select the small set of features, a subspace of features from the corpus of training data may be randomly sampled according to a probability distribution over the set of features where a probability may be assigned to each of the features that is proportional to the square of the Euclidean norms of the rows of left singular vectors of a matrix of the features representing the corpus of training texts. The small set of features may classify texts using only the relevant features among a very large number of training features.
摘要:
An improved system and method is provided for feature selection for text classification using subspace sampling. A text classifier generator may be provided for selecting a small set of features using subspace sampling from the corpus of training data to train a text classifier for using the small set of features for classification of texts. To select the small set of features, a subspace of features from the corpus of training data may be randomly sampled according to a probability distribution over the set of features where a probability may be assigned to each of the features that is proportional to the square of the Euclidean norms of the rows of left singular vectors of a matrix of the features representing the corpus of training texts. The small set of features may classify texts using only the relevant features among a very large number of training features.
摘要:
Methods and system for optimally allocating ad space to advertisers on a webpage viewed by a user in a single browsing session includes identifying a plurality of advertisement stories that match the content of the webpage. An advertisement pool is generated using the identified ad stories. Each ad story in the advertisement pool includes one or more advertisement pages and is associated with corresponding ad value. An ad story from the pool of ad stories is chosen by dynamically evaluating ad value associated with each ad story in the pool based on continued surfing by the user such that the identified ad story provides the maximum ad value when rendered on the webpage. The identified ad story is scheduled for rendering on the webpage while providing relevant ad content at the webpage.
摘要:
Embodiments are directed towards clustering cookies for identifying unique mobile devices for associating activities over a network with a given mobile device. The cookies are clustered based on a Bayes Factor similarity model that is trained from cookie features of known mobile devices. The clusters may be used to determine the number of unique mobile devices that access a website. The clusters may also be used to provide targeted content to each unique mobile device.
摘要:
Method, system, and programs for computing similarity. Input data is first received from one or more data sources and then analyzed to obtain an input feature vector that characterizes the input data. An index is then generated based on the input feature vector and is used to archive the input data, where the value of the index is computed based on an improved Johnson-Lindenstrass transformation (FJLT) process. With the improved FJLT process, first, the sign of each feature in the input feature vector is randomly flipped to obtain a flipped vector. A Hadamard transformation is then applied to the flipped vector to obtain a transformed vector. An inner product between the transformed vector and a sparse vector is then computed to obtain a base vector, based on which the value of the index is determined.
摘要:
Embodiments are directed towards employing a playful incentive to encourage users to provide feedback that is useable to train a classifier. The classifier being associated with any of a variety of different settings, including but not limited to classifying: messages as ham/spam, images, advertising, bookmarking, music, videos, photographs, shopping, or the like. An animated image, such as a pet, provides an interface to the classifier that encourages and responds to user feedback. Users may share their classifiers or aspects thereof with other users to enable a community of knowledge to be applied to a classification task, while preserving privacy of the user feedback. One form of sharing may be within the context of a competitive game. Various evaluations may be performed on a classifier to indicate user feedback consistency, or quality. Classifiers may also be used to provide users with advertisements, products, or services based on the user's feedback.
摘要:
Embodiments are directed towards generating a unified user account trustworthiness system through user account trustworthiness scores. A trusted group of user accounts may be identified for a given action by grouping a plurality of user accounts into tiers based on a trustworthiness score of each user account for the given action. The tiers and/or trustworthiness scores may be employed to classify an item, such as a message as spam or non-spam, based on input from the user accounts. The trustworthiness scores may also be employed to determine if a user account is a robot account or a human account. The trusted group for a given action may dynamically evolve over time by regrouping the user accounts based on modified trustworthiness scores. A trustworthiness score of an individual user account may be modified based on input received from the individual user account and input from other user accounts.
摘要:
A system and method for implementing a multi-step challenge and response test includes steps or acts of: using an input/output subsystem for presenting a series of challenges to a user that require said user to correctly solve each challenge before a next challenge is revealed to the user; receiving the user's response to each challenge; and submitting a last response in the series of challenges to a server for validation. The method further includes: using a processor device configured to perform for each challenge in the series of challenges: internally validating the response by comparing the user's response to a correct response; and using the user's response, decrypting the next challenge to reveal the next challenge; wherein the next challenge remains obfuscated until a previous challenge is correctly solved.
摘要:
Embodiments of the present inversion relate to a two-pass compression scheme that achieves compression performance on par with existing methods while admitting individual message decompression. These methods provide both storage savings and lower end-user latency. They preserve the advantages of standard text compression in exploiting short-range similarities in data, while introducing a second step to take advantage of long-range similarities often present in certain types of structured data, e.g. email archival files.
摘要:
An image CAPTCHA having one or more images, a challenge, and a correct answer to the challenge is constructed by selecting the one or more images from a plurality of candidate images based at least in part on each image's public information and private information. The private information of each of the images is accessible only to an entity responsible for constructing the CAPTCHA. Optionally, the one or more images are selected further based on the specific type of the CAPTCHA to be constructed.