Biomedical subjects

I Ritov

Publications and source records attributed to I Ritov.

4 recordsLinked to original sources

PubMed2000

The role of expectations in comparisons.

Expectations are proposed as a unifying framework for explaining a variety of findings on comparative judgment. Expectations may pertain to either the features of each separate object or their simultaneous occurrence in all relevant objects. Two experiments demonstrate that inducing expectations by varying the frequency with which a component occurs, as well as the frequency with which it is shared by the compared objects, results in augmented weighting of unexpected components. Expectations can arise not only from experienced frequencies but also from an inferred set of alternatives. Features of cohesive stimuli are shown to be more expected than features of noncohesive stimuli, in the latter sense. The relatively higher weighting of distinctive features in cohesive stimuli, as well as the higher weight assigned to structurally aligned differences, could thus reflect modifications in feature expectedness. Further experiments show how task-dependent weighting interacts with expectations to produce asymmetries between similarity and difference judgments. Finally, it is argued that changes in expectations regarding objects' attributes can explain context effects across different domains, including some types of preference reversals.

Cognition↗

PubMed1999

Protected Values and Omission Bias.

Protected values (PVs) are those that people think should not be traded off. Baron and Spranca (1997) proposed that such values result from rules concerning actions (as opposed to values for outcomes). This proposal implies that PVs should show a particularly large bias against harmful acts that undermine the value in question, as opposed to harmful omissions (omission bias). We found this correlation between PVs and omission bias in 3 experiments, using stimuli of the sort that we used before to demonstrate omission bias. In 2 experiments, we also found a weak tendency for PVs to be associated with lack of concern for the number of acts involved, which is analogous to earlier results showing an association with lack of concern for the quantity of outcomes. Finally, 1 experiment showed that some people are willing to sacrifice values to prevent losses more than they are willing to sacrifice these values for gains. Copyright 1999 Academic Press.

Journal Article↗

PubMed1990

Differential weighting of common and distinctive components.

We investigated possible explanations of the finding that the relative weight (W) of common components in similarity judgments is higher for verbal than for pictorial stimuli. A serial presentation of stimulus components had no effect on verbal stimuli; it increased the impact of both common and distinctive components of pictorial stimuli but did not affect their relative weight. On the other hand, W was increased by manipulations that reduced the cohesiveness of composite pictures, such as separating, scrambling, and mixing their components. Furthermore, W was decreased by manipulations that enhanced the cohesiveness of composite verbal stimuli by imposing structure on their components. Verbal and pictorial representations of the same stimuli yielded no systematic differences in W.

Adult↗

PubMedDate not supplied

Omission bias and pertussis vaccination.

BACKGROUND: Several laboratory studies have suggested that many people favor potentially harmful omissions over less harmful acts. The authors studied the role of this omission bias in parents' decisions whether to vaccinate their children against pertussis. METHODS: Two hundred mail surveys were sent to subscribers to a magazine that had published articles favoring and opposing pertussis vaccination. Subjects were asked about their beliefs about the vaccine and the disease, and whether they had vaccinated their own children or planned to, and they were given test items to identify omission bias in their reasoning. RESULTS: One hundred and three subjects (52%) responded to the survey. Respondents who reported they did not or would not allow their children to be vaccinated (n = 43; 41%) were more likely to believe that vaccinating was more dangerous than not vaccinating (p < 0.001). They were also more likely to exhibit omission bias (p = 0.004), holding constant their stated beliefs about the danger of the vaccine. CONCLUSIONS: Omission bias plays a role in decisions not to vaccinate with pertussis vaccine, beyond the role played by belief about the risk of vaccination.

Adult↗