On the use of elo rating on harness racing results in the genetic evaluation of trotter

Abstract

The official results of trotters in Italian harness racings have been used to get AM-BLUP estimates of genetic parameters, EBVs and rTI of three groups of traits: speed (racing time, annual best time, best time in career between 2- and 5-year old), earnings (earnings/start, annual earnings, total earnings between 2- and 5-year old) and Elo system traits (underlying performance and final rating). The Elo system has been used for half a century in chess players rating, and it has been modified and fitted to several games and sports: it has already been used for genetic evaluation of sport horses in France. The highest heritability estimates in each group of traits have been found for best time (.430±.014), total earnings (.271±.013) and Elo final rating (.270±.008). The choice of "k", the Elo ratings updating factor, did not show a key role in affecting the results. The underlying performance heritability and repeatability have been estimated .159±.004 and .420±.007 respectively. The Elo-based systems proved to be very promising in objectively evaluating trotters.