where formula_1 is the order of the schema, formula_15 is the length of the code, formula_16 is the probability of mutation and formula_17 is the probability of crossover. So a schema with a shorter defining length formula_2 is less likely to be disrupted.An often misunderstood point is why the Schema Theorem is an "inequality" rather than an equality. The answer is in fact simple: the Theorem neglects the small, yet non-zero, probability that a string belonging to the schema formula_5 will be created "from scratch" by mutation of a single string (or recombination of two strings) that did "not" belong to formula_5 in the previous generation.