"x is approximately equivalent to y if it is the case that x is equivalent, identical or near-equivalent to y" . "is approximately equivalent to" . . "The precise meaning of this property is dependent upon some contexts. It is intended to group multiple possible formalisms. Possibilities include a probabilistic interpretation, for example, Pr(x=y) > 0.95. Other possibilities include reified statements of belief, for example, \"Database D states that x=y\"" . .