THE EXPECTANCY BIAS MODEL OF SELECTIVE ASSOCIATIONS - THE RELATIONSHIP OF JUDGMENTS OF CS DANGEROUSNESS, CS-UCS SIMILARITY AND PRIOR FEAR TO A-PRIORI AND A-POSTERIORI COVARIATION ASSESSMENTS

This paper describes three experiments examining predictions from the expectancy bias model of selective associations (Davey, 1995). In a si mulated 'threat' conditioning procedure, Experiment 1 showed that UCS expectancy following both ontogenetic and phylogenetic CSs was signifi cantly predicted by: (1) ratings of the dangerousness of the CS, perce ptions of CS-UCS similarity, and level of prior fear to the CS; and (2 ) ratings of CS-UCS similarity on the dimensions of valence, arousal a nd anxiety. Experiment 2 used a covariation assessment procedure which confirmed the findings of Experiment 1, and also showed that both phy logenetic and ontogenetic fear-relevant CSs exhibited both a priori an d a posteriori covariation biases. Experiment 3 found that Ss high and low in fear to a fear-relevant CS exhibited a significant a priori UC S expectancy bias, but this bias was significantly larger in high fear Ss. Only high fear Ss exhibited an a posteriori covariation bias. The se results are consistent with predictions from the expectancy bias mo del.