Multi-task convolutional neural network for behavior sequence embedding modeling

A computer-implemented method comprising:

• accessing, by at least one server from one or more servers of an online transaction platform, a sequence of page browsing signals corresponding to user interactions of a user with the online transaction platform, each of the page browsing signals corresponding to a position in the sequence;
• selecting, by at least one server from the one or more servers, a plurality of temporally distinct portions of the sequence of page browsing signals, the plurality of temporally distinct portions comprising at least a first portion spanning a first temporal window of user interactions and a second portion spanning a second, longer temporal window of user interactions that overlaps the first temporal window;
• generating, by at least one server from the one or more servers, a plurality of sequence embeddings, wherein each sequence embedding is generated for a corresponding temporally distinct portion from the plurality of temporally distinct portions using the page browsing signals in the corresponding temporally distinct portion and positional information indicative of an order of the page browsing signals in the corresponding temporally distinct portion;
• predicting, by at least one server from the one or more servers utilizing a multi-task model with multi-range kernels trained to detect fraudulent activity in online transactions, a fraud risk for each of the plurality of sequence embeddings in parallel, wherein each multi-range kernel convolves over a different temporal span corresponding to a different one of the plurality of temporally distinct portions;
• and
• causing, by at least one server from the one or more servers, an action to be performed on the online transaction platform based on the fraud risk for at least one of the plurality of sequence embeddings, the action comprising at least one of blocking a transaction involving the user, freezing an account of the user, or closing the account of the user.

A computer system comprising:

• one or more processors;
• and
• one or more computer storage medium storing computer-usable instructions that, when used by the one or more processors, causes the computer system to perform operations comprising:
• accessing, by at least one server from one or more servers of an online transaction platform, a sequence of page browsing signals corresponding to user interactions of a user with the online transaction platform, each of the page browsing signals corresponding to a position in the sequence;
• selecting, by at least one server from the one or more servers, a plurality of temporally distinct portions of the sequence of page browsing signals, the plurality of temporally distinct portions comprising at least a first portion spanning a first temporal window of user interactions and a second portion spanning a second, longer temporal window of user interactions that overlaps the first temporal window;
• generating, by at least one server from the one or more servers, a plurality of sequence embeddings, wherein each sequence embedding is generated for a corresponding temporally distinct portion from the plurality of temporally distinct portions using the page browsing signals in the corresponding temporally distinct portion and positional information indicative of an order of the page browsing signals in the corresponding temporally distinct portion;
• predicting, by at least one server from the one or more servers utilizing a multi-task model with multi-range kernels trained to detect fraudulent activity in online transactions, a fraud risk for each of the plurality of sequence embeddings in parallel, wherein each multi-range kernel convolves over a different temporal span corresponding to a different one of the plurality of temporally distinct portions;
• and
• causing, by at least one server from the one or more servers, an action to be performed on the online transaction platform based on the fraud risk for at least one of the plurality of sequence embeddings, the action comprising at least one of blocking a transaction involving the user, freezing an account of the user, or closing the account of the user.