Cue Validity - Definition of Cue Validity

Definition of Cue Validity

Formally, the cue validity of a feature with respect to category has been defined in the following ways:

• As the conditional probability ; see Reed (1972), Rosch & Mervis (1975), Rosch (1978).
• As the deviation of the conditional probability from the category base rate, ; see Edgell (1993), Kruschke & Johansen (1999).
• As a function of the linear correlation; see Smedslund (1955), Castellan (1973), Sawyer (1991), Busemeyer, Myung & McDaniel (1993).
• Other definitions; see Restle (1957), Martignon et al. (2003).

For the definitions based on probability, a high cue validity for a given feature means that the feature or attribute is more diagnostic of the class membership than a feature with low cue validity. Thus, a high-cue validity feature is one which conveys more information about the category or class variable, and may thus be considered as more useful for identifying objects as belonging to that category. Thus, high cue validity expresses high feature informativeness. For the definitions based on linear correlation, the expression of "informativeness" captured by the cue validity measure is not the full expression of the feature's informativeness (as in mutual information, for example), but only that portion of its informativeness that is expressed in a linear relationship. For some purposes, a bilateral measure such as the mutual information or category utility is more appropriate than the cue validity.