摘要 |
<p>Methods and apparatus for determining whether a provided object track is abnormal, recognising suspicious behaviour, an object track being a set of values of a physical property of an object measured over a period of time, the method comprising: providing a model comprising one or more functions, each function being representative of an object track that is defined to be normal; assigning the provided object track to a function; and comparing the provided object track to the assigned function to determine whether that object track is abnormal. Providing the model comprises: for each of a plurality of objects, determining an object track, wherein the determined object tracks are defined as normal object tracks; and using the determined tracks, performing a Gaussian Processes based Variational Bayes Expectation Maximisation process to learn the one or more functions.</p> |