Published online by Cambridge University Press: 09 March 2007
A preliminary investigation into the structure of the competing sport horse population within the UK for the year 2000 was undertaken, comprising 30 974 horses and 39 679 individual performances. All performance data were expressed as total lifetime winnings. The level of non-winning horses, expressed as a percentage, was high in all disciplines: dressage 22%, eventing 50% and show jumping 23%. The percentage of horses competing in disciplines at the highest recognized level was small: dressage 2.5%, eventing 10% and show jumping 6.5%. Highest earners for all disciplines all earned considerably more than the threshold for highest performance level in their respective discipline (×2.2 dressage, ×24 eventing, ×365 show jumping). Data for all three disciplines were highly skewed. Structural analysis of the distributions by level showed a highly skewed hypogeometric distribution at the lowest level of competition for all disciplines, uniform distribution at intermediate levels (bimodal tendencies were observed within dressage) and normal distribution at advanced levels. Product–moment correlations showed a significant correlation between show jumping and eventing (0.228, P<0.01). Problems with data availability and presentation may mean that up to 12.9% of the population may have had a confounding effect on the results of this study.