Embodiments of the present invention provide a computer-implemented method of determining temporal behaviour of an object, comprising receiving image data comprising data representing a plurality of images, at least some of the images comprising one or more cells, determining a plurality of characteristics of at least one feature in each of one or more of the plurality of images, determining a confidence value representing a confidence that one of the cells in a first one of the plurality of images corresponds to a feature in a second one of the plurality images, wherein the confidence value is based upon the characteristics of the feature in the second image and the characteristics of the cell, and identifying the cell in the second one of the plurality of images based upon the confidence value.