An information processing apparatus for generating a similarity determination algorithm determining a similarity between a pair of data. The apparatus includes: a feature-quantity-extraction expression list generation mechanism generating a feature quantity-extraction expression list including a plurality of feature-quantity-extraction expressions including a plurality of operators by updating the feature-quantity extraction expression list of a preceding generation; a calculation mechanism inputting first and second data given as teacher data into each of the feature-quantity-extraction expressions in the feature-quantity-extraction expression list to calculate a feature quantity corresponding to each of the first and the second data; an evaluation-value calculation mechanism calculating the evaluation value of each of the feature-quantity-extraction expressions using the calculated feature quantities and a similarity between the first and the second data; and a similarity-calculation expression estimation mechanism estimating a similarity calculation expression for calculating a similarity between the first and the second data.