title: Some examples of double exponential fitness functions.
abstract: The advantages of using a double exponential fitness function are pointed out for the analysis of differential survival data. The uses of this type of function are illustrated on Bumpus' (1898) data on the survival of English sparrows after a severe storm and also on Cook and O'Donald's (1971) data on the over-winter survival of a large sample of snails.
mesh_terms: D000818:Animals; D005075:Biological Evolution; D001717:Birds; D008954:Models, Biological; D012641:Selection, Genetic; D012908:Snails