Faceranked uses the theory of paired comparison analysis. Wikipedia defines this as follows:
"In paired comparison analysis, also known as paired choice analysis, a range of options are compared and the results are tallied to find an overall winner. A range of plausible options is listed. Each option is compared against each of the other options, determining the preferred option in each case."
There are numerous ways and algorithms to perform "Paired Comparison" and Faceranked has investigated a large quantity of them in order to find the best solution.
We are very proud that we have managed to do this, see for yourself!