Confirming expectations in asymmetric and symmetric social hypothesis testing

This article examines individuals' expectations in a social hypothesis testing task. Participants selected questions from a list to investigate the presence of personality traits in a target individual. They also identified the responses that they expected to receive and the likelihood of the expected responses. The results of two studies indicated that when people asked questions inquiring about the hypothesized traits that did not entail strong a priori beliefs, they expected to find evidence confirming the hypothesis under investigation. These confirming expectations were more pronounced for symmetric questions, in which the diagnosticity and frequency of the expected evidence did not conflict. When the search for information was asymmetric, confirming expectations were diminished, likely as a consequence of either the rareness or low diagnosticity of the hypothesis-confirming outcome. We also discuss the implications of these findings for confirmation bias.     

Integration of base rates and new information in an abstract hypothesis‐testing task

In two studies, we investigated how people use base rates and the presence versus the absence of new information to judge which of two hypotheses is more likely. Participants were given problems based on two decks of cards printed with 0–4 letters. A table showed the relative frequencies of the letters on the cards within each deck. Participants were told the letters that were printed on or absent from a card the experimenter had drawn. Base rates were conveyed by telling participants that the experimenter had chosen the deck by drawing from an urn containing, in different proportions, tickets marked either ‘deck 1’ or ‘deck 2’. The task was to judge from which of the two decks the card was most likely drawn. Prior probabilities and the evidential strength of the subset of present clues (computed as ‘weight of evidence’) were the only significant predictors of participants’ dichotomous (both studies) and continuous (Study 2) judgments. The evidential strength of all clues was not a significant predictor of participants’ judgments in either study, and no significant interactions emerged. We discuss the results as evidence for additive integration of base rates and the new present information in hypothesis testing.     

New knowledge for old credences: Asymmetric information search about in-group and out-group members

Three experiments examined how people gather information on in-group and out-group members. Previous studies have revealed that category-based expectancies bias the hypothesis-testing process towards confirmation through the use of asymmetric-confirming questions (which are queries where the replies supporting the prior expectancies are more informative than those falsifying them). However, to date there is no empirical investigation of the use of such a question-asking strategy in an intergroup context. In the present studies, participants were asked to produce (Study 1) or to choose (Studies 2 and 3) questions in order to investigate the presence of various traits in an in-group or an out-group member. Traits were manipulated by valence and typicality. The results revealed that category-based expectancies do not always lead to asymmetric-confirming testing: whereas participants tended to ask questions that confirmed positive in-group and negative out-group stereotypical attributes, they used a more symmetric strategy when testing for the presence of negative in-group or positive out-group traits. Moreover, Study 3 also revealed a moderation effect of in-group identification. The findings point to the role played by motivational factors associated with preserving a positive social identity. Possible consequences of these hypothesis-testing processes in preserving a positive social identity for intergroup relations are discussed.     

Looking for honesty: The primary role of morality (vs. sociability and competence) in information gathering

Research on the two fundamental dimensions of social judgment, namely warmth and competence, has shown that warmth has a primary and a dominant role in information gathering about others. In two studies we examined whether the sociability and morality components of warmth play distinct roles in such a process. Study 1 (N = 60) investigated which traits were mostly selected when forming impressions about others. The results showed that, regardless of the task goal, traits related to morality and sociability were differently processed. Furthermore, participants were more interested in obtaining information about morality than about sociability when asked to form a global impression about others. Study 2 (N = 98) explored the adoption of asymmetric/symmetric strategies when asking questions to make inferences on others. As predicted, participants adopted an asymmetrically disconfirming strategy on morality traits, while they looked for more symmetrical evidence on sociability or competence traits. Overall, our findings indicated a distinct and a dominant role of the moral component of warmth in the information‐gathering process. Copyright © 2010 John Wiley & Sons, Ltd.     

Preferences for different questions when testing hypotheses in an abstract task: Positivity does play a role, asymmetry does not

Previous studies on hypothesis-testing behaviour have reported systematic preferences for posing positive questions (i.e., inquiries about features that are consistent with the truth of the hypothesis) and different types of asymmetric questions (i.e., questions where the hypothesis confirming and the hypothesis disconfirming responses have different evidential strength). Both tendencies can contribute - in some circumstances - to confirmation biases (i.e., the improper acceptance or maintenance of an incorrect hypothesis). The empirical support for asymmetric testing is, however, scarce and partly contradictory, and the relative strength of positive testing and asymmetric testing has not been empirically compared. In four studies where subjects were asked to select (Experiment 1) or evaluate (Experiments 2-4) questions for controlling an abstract hypothesis, we orthogonally balanced the positivity/negativity of questions by their symmetry/asymmetry (Experiments 1-3), or by the type of asymmetry (confirmatory vs disconfirmatory; Experiment 4). In all Experiments participants strongly preferred positive to negative questions. Their choices were on the other hand mostly unaffected by symmetry and asymmetry in general, or - more specifically - by different types of asymmetry. Other results indicated that participants were sensitive to the diagnosticity of the questions (Experiments 1-3), and that they preferred testing features with a high probability under the focal hypothesis (Experiment 4). In the discussion we argue that recourse to asymmetric testing - observed in some previous studies using more contextualized problems - probably depends on context-related motivations and prior knowledge. In abstract tasks, where that knowledge is not available, more simple strategies - such as positive testing - are prevalent.     

The perceptual wink model of non-switching attentional blink tasks

The attentional blink (AB) is a temporary deficit for a second target (T2) when that target appears after a first target (T1). Although sophisticated models have been developed to explain the substantial AB literature in isolation, the current study considers how the AB relates to perceptual dynamics more broadly. We show that the time-course of the AB is closely related to the time course of the transition from positive to negative repetition priming effects in perceptual identification. Many AB tasks involve a switch between a T1 defined in one manner and a T2 defined in a different manner. Other AB tasks are non-switching, with all targets belonging to the same well-known category (e.g., letter targets versus number distractors) or sharing the same perceptual feature. We propose that these non-switching AB tasks reflect perceptual habituation for the target-defining attribute; thus, a ‘perceptual wink’, with perception of one attribute (target identity) undisturbed while perception of another (target detection) is impaired. On this account, the immediate benefit following T1 (lag-1 sparing) reflects positive repetition priming and the subsequent deficit (the blink) reflects negative repetition priming for the realization that a target occurred. In developing the perceptual wink model, we extended the nROUSE model of perceptual priming to explain the results of two new experiments combining the AB and identity repetitions. This establishes important connections between non-switching AB tasks and perceptual dynamics.     

Response demands and the recruitment of heuristic strategies in syllogistic reasoning

Two experiments investigated whether dealing with a homogeneous subset of syllogisms with time-constrained responses encouraged participants to develop and use heuristics for abstract (Experiment 1) and thematic (Experiment 2) syllogisms. An atmosphere-based heuristic accounted for most responses with both abstract and thematic syllogisms. With thematic syllogisms, a weaker effect of a belief heuristic was also observed, mainly where the correct response was inconsistent with the atmosphere of the premises. Analytic processes appear to have played little role in the time-constrained condition, whereas their involvement increased in a self-paced, unconstrained condition. From a dual-process perspective, the results further specify how task demands affect the recruitment of heuristic and analytic systems of reasoning. Because the syllogisms and experimental procedure were the same as those used in a previous neuroimaging study by Goel, Buchel, Frith, and Dolan (2000), the result also deepen our understanding of the cognitive processes investigated by that study.     

Outcome evaluation in brief mother-infant psychotherapies: Report on 75 cases

The effects of brief mother–infant psychotherapies (maximum of 10 sessions) were examined in cases of functional and behavioral disturbances in children less than 30 months old. Seventy-five mother-infant dyads were assessed prior to treatment, at 1 week, and 6 months after therapy ended. The outcome measures were changes in the infant's symptoms, the behavioral interactions between mother and infant, and maternal representations. The effect of two forms of intervention—Psychodynamic Therapy and Interaction Guidance Therapy—were compared. Results indicated a significant symptom reduction; dyadic interactions became more harmonious (mothers became less intrusive and infants more cooperative). Maternal self-esteem grew significantly and negative affects decreased. Improvements lasted as least several months, with some positive improvement detected at the 6-month follow-up. No major difference in outcome was found between the effects of the two forms of intervention. Within the limitations of research in a clinical context, this study suggests that brief mother–infant psychotherapies are a cost-effective method of early intervention.     

Missing the dog that failed to bark in the nighttime: on the overestimation of occurrences over non-occurrences in hypothesis testing

In three studies, we investigated whether and to what extent the evaluation of two mutually exclusive hypotheses is affected by a feature-positive effect, wherein present clues are weighted more than absent clues. Participants (N = 126) were presented with abstract problems concerning the most likely provenance of a card that was drawn from one of two decks. We factored the correct response (the hypothesis favored by the consideration of all clues) and the ratio of present-to-absent features in each set of observations. Furthermore, across the studies, we manipulated the presentation format of the features’ probabilities by providing the probability distributions of occurrences (Study 1), non-occurrences (Study 3) or both (Study 2). In all studies, both participant preference and accuracy were mostly determined by an over-reliance on present features. Moreover, across participants, both confidence in the responses and the informativeness of the present clues correlated positively with the number of responses given in line with an exclusive consideration of present features. These results were mostly independent of both the rarity of the absent clues and the presentation format. We concluded that the feature-positive effect influences hypothesis evaluation, and we discussed the implications for confirmation bias.