Abstract: A computer-implemented method is provided that includes identifying an input dataset formatted as an input matrix, the input matrix including a plurality of rows and a plurality of columns. The computer-implemented method also includes dividing the input matrix into a plurality of input matrix blocks. Further, the computer-implemented method includes distributing the input matrix blocks to a plurality of different machines across a distributed filesystem, and sampling, by at least two of the different machines in parallel, at least two of the input matrix blocks. Finally, the computer-implemented method includes generating at least one sample matrix based on the sampling of the at least two of the input matrix blocks.

Abstract: An input data set with a plurality of item descriptors comprising respective time series observations is identified. A routing directive indicating a predicate to be evaluated to determine whether a particular item descriptor is to be included in a training data set for a first learning algorithm is obtained. A plurality of learning algorithms are trained using training data sets derived from the input data set according to respective routing directives, and the trained algorithms are stored.

Abstract: A messaging system provides recommendations of content that account holders of the messaging system might be interested in engaging with. In order to determine what to recommend, the messaging system generates a model of account holder engagement behavior organized by type of engagement. The model parameters are trained on differences between expected engagement behavior based on past data and actual engagement behavior, and include a set of common factor matrices that are trained using data from more than on engagement type. As a consequence, engagement behavior of other account holders with respect to other types of engagements different than the one sought to be recommended serves as a partial basis for determining what engagements of the sought-after type are recommended.

Abstract: A computer-implemented method is provided that includes identifying an input dataset formatted as an input matrix, the input matrix including a plurality of rows and a plurality of columns. The computer-implemented method also includes dividing the input matrix into a plurality of input matrix blocks. Further, the computer-implemented method includes distributing the input matrix blocks to a plurality of different machines across a distributed filesystem, and sampling, by at least two of the different machines in parallel, at least two of the input matrix blocks. Finally, the computer-implemented method includes generating at least one sample matrix based on the sampling of the at least two of the input matrix blocks.

Abstract: A computer-implemented method is provided that includes identifying an input dataset formatted as an input matrix, the input matrix including a plurality of rows and a plurality of columns. The computer-implemented method also includes dividing the input matrix into a plurality of input matrix blocks. Further, the computer-implemented method includes distributing the input matrix blocks to a plurality of different machines across a distributed filesystem, and sampling, by at least two of the different machines in parallel, at least two of the input matrix blocks. Finally, the computer-implemented method includes generating at least one sample matrix based on the sampling of the at least two of the input matrix blocks.

Abstract: A computer-implemented method is provided that includes identifying an input dataset formatted as an input matrix, the input matrix including a plurality of rows and a plurality of columns. The computer-implemented method also includes dividing the input matrix into a plurality of input matrix blocks. Further, the computer-implemented method includes distributing the input matrix blocks to a plurality of different machines across a distributed filesystem, and sampling, by at least two of the different machines in parallel, at least two of the input matrix blocks. Finally, the computer-implemented method includes generating at least one sample matrix based on the sampling of the at least two of the input matrix blocks.