It is valid provided we can express the irregularity, with a fair degree of approximation, in terms of the hypothetical assumption that one only of the recurring frequencies of the 'middle frequencies' so occurs in any selection according to predecessors that no after effects The quasi Bernoulli formulae (symbol: F′) also remain unambiguous for chancelike sequences (according to the new definition), although 'F′' now symbolizes only a middle frequency.