1. A method of grouping a plurality of contestants of a competitive event according to an ability level of each of the plurality of contestants prior to the event, comprising the steps of: retrieving performance result data for a plurality of previous competitive events for each of the plurality of contestants; generating, by a processor, a scaled event rate for each of the plurality of contestants based on a standardized event venue parameter, an actual event venue parameter, and a race distance and the retrieved performance result data; indexing the scaled event rates based on a predefined fraction of an average of a total number of scaled event rates; creating, by a processor prior to the event, a plurality of ability level groups of contestants according to an average of the indexed values, comprising: a first ability level group defined by a first ability index value and a second ability index value, and a second ability level group defined by a third ability index value and a fourth ability index value, and allocating a prize purse for each of the plurality of ability level groups according to the number of ability level groups created and a rank of each of the plurality of ability level groups created, wherein at the first ability level group and the second ability level group comprise at least a predetermined number of contestants.