Average numbers of observers to break various race equalities, as shown in blue or black data points whose error bars denote standard deviations.

<p>The non-spurious race equality is <i>RE</i>₁. Data from 6 observers were tested for race equalities <i>RE</i>₁ and <i>RE</i>_<i>i</i> for <i>i</i> ≥ 5 and data from 8 observers were tested for <i>RE</i>₂, <i>RE</i>₃, and <i>RE</i>₄. Applying a test of a given race equality to all the observers gives a number of observers breaking this equality, and the average of this number over 80 (for <i>RE</i>_<i>i</i> with <i>i</i> = 2–5) or 320 (for <i>RE</i>₁ and <i>RE</i>_<i>i</i> with <i>i</i> > 5) tests, each characterized by a unique set of parameters in the testing method, gives a data point (blue cross or black square). The background shadings visualize the probabilities of at least a certain number of observers breaking a true race equality accidentally, shadings in red hue indicate probabilities larger than 0.05. Note that the number of observers in this probability representation is an integer number, whereas the data points are generally non-integers since they are averages of integer numbers.