Performance as a function of the number of rival responses.

<p>In both plots, the black curve shows performance of the computational system using distributional similarities (<i>DST</i>), colour & textons for appearance, the MIRRORING algorithm and 512 already-known appearances. The red curve shows baseline chance performance. The horizontal axes show the number of incorrect rival answers that are presented alongside the correct answer. The left hand end of each horizontal axis corresponds to just one rival, which is the condition used in all other experiments (<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0058074#pone-0058074-g006" target="_blank">figures 6</a> & <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0058074#pone-0058074-g007" target="_blank">7</a>). The thicker parts of the curves indicate the range of numbers of rival that are relevant to human learning.