Outlier detection in textual data

A system comprising:

• one or more hardware processors and associated memory that implement a computing system, configured to:
• receive a sequence of text records;
• generate a record fingerprint for a text record in the sequence;
• select, from a set of clusters, a closest cluster to the text record based at least in part on distances between the record fingerprint and respective cluster fingerprints of the clusters;
• in response to a determination that a distance between the record fingerprint and a cluster fingerprint of the closest cluster exceeds a distance threshold:
• create a new cluster in the set of clusters as an outlier cluster, wherein the outlier cluster comprises the text record as a sole member;
• update a cluster fingerprint of the outlier cluster based at least in part on the record fingerprint of the text record;
• and
• store information about the outlier cluster as an outlier class in an outlier class library;
• and
• use the outlier class to identify one or more additional outlier records.

One or more non-transitory computer-accessible storage media storing program instructions that when executed on one or more processors of a computing system cause the computing system to:

• receive a sequence of text records;
• generate a record fingerprint for a text record in the sequence;
• select, from a set of clusters, a closest cluster to the text record based at least in part on distances between the record fingerprint and respective cluster fingerprints of the clusters;
• in response to a determination that a distance between the record fingerprint and a cluster fingerprint of the closest cluster exceeds a distance threshold:
• create a new cluster in the set of clusters as an outlier cluster, wherein the outlier cluster comprises the text record as a sole member;
• update a cluster fingerprint of the outlier cluster based at least in part on the record fingerprint of the text record;
• and
• store information about the outlier cluster as an outlier class in an outlier class library;
• and
• use the outlier class to identify one or more additional outlier records.