Relative frequency refers to the number of times an event occurs compared to the total number of times it could possibly happen. It shows how likely or often something is to occur relative to other possibilities. Full definition
These genes can increase in relative frequency in a population even if they reduce the odds that each organism will reproduce. (science.sciencemag.org)
Cases have been reported in almost all large breeds of dogs, with the disease appearing with relative frequency only in the German Shepherd. (lowchensaustralia.com)
Food avoidance also occurs with relative frequency among cats that are placed in boarding kennels. (www2.vet.cornell.edu)