Cue Validity - Examples

Examples

As an example, let us consider the domain of "numbers" and allow that every number has an attribute (i.e., a cue) named "is_positive_integer", which we call, and which adopts the value 1 if the number is actually a positive integer. Then we can inquire what the validity of this cue is with regard to the following classes: {rational number, irrational number, even integer}:

• If we know that a number is a positive integer we know that it is a rational number. Thus, the cue validity for is_positive_integer as a cue for the category rational number is 1.
• If we know that a number is a positive integer then we know that it is not an irrational number. Thus, the cue validity for is_positive_integer as a cue for the category irrational number is 0.
• If we know only that a number is a positive integer, then its chances of being even or odd are 50-50 (there being the same number of even and odd integers). Thus, the cue validity for is_positive_integer as a cue for the category even integer is 0.5, meaning that the attribute is_positive_integer is entirely uninformative about the number's membership in the class even integer.

In perception, "cue validity" is often short for ecological validity of a perceptual cue, and is defined as a correlation rather than a probability (see above). In this definition, an uninformative perceptual cue has an ecological validity of 0 rather than 0.5.