Information relevance, working memory, and the consideration of alternatives

People routinely focus on one hypothesis and avoid consideration of alternative hypotheses on problems requiring decisions between possible states of the world--for example, on the “pseudodiagnosticity” task (Doherty, Mynatt, Tweney, & Schiavo, 1979). In order to account for behaviour on such “inference” problems, it is proposed that people can hold in working memory, and operate upon, but one alternative at a time, and that they have a bias to test the hypothesis they think true. In addition to being an ex post facto explanation of data selection in inference tasks, this conceptualization predicts that there are situations in which people will consider alternatives. These are:

1. “action” problems, where the alternatives are possible courses of action;

2. “inference” problems, in which evidence favours an alternative hypothesis.

Experiment 1 tested the first prediction. Subjects were given action or inference problems, each with two alternatives and two items of data relevant to each alternative. They received probabilistic information about the relation between one datum and one alternative and picked one value from among the other three possible pairs of such relations. Two findings emerged; (1) a strong tendency to select information about only one alternative with inferences; and (2) a strong tendency, compared to inferences, to select information about both alternatives with actions.

Experiment 2 tested the second prediction. It was predicted that data suggesting that one alternative was incorrect would lead many subjects to consider, and select information about, the other alternative. For actions, it was predicted that this manipulation would have no effect. Again the data were as predicted.     

Seeking Confirmation Is Rational for Deterministic Hypotheses

The tendency to test outcomes that are predicted by our current theory (the confirmation bias) is one of the best‐known biases of human decision making. We prove that the confirmation bias is an optimal strategy for testing hypotheses when those hypotheses are deterministic, each making a single prediction about the next event in a sequence. Our proof applies for two normative standards commonly used for evaluating hypothesis testing: maximizing expected information gain and maximizing the probability of falsifying the current hypothesis. This analysis rests on two assumptions: (a) that people predict the next event in a sequence in a way that is consistent with Bayesian inference; and (b) when testing hypotheses, people test the hypothesis to which they assign highest posterior probability. We present four behavioral experiments that support these assumptions, showing that a simple Bayesian model can capture people's predictions about numerical sequences (Experiments 1 and 2), and that we can alter the hypotheses that people choose to test by manipulating the prior probability of those hypotheses (Experiments 3 and 4).     

Test of the analysis of competing hypotheses in legal decision‐making

The analysis of competing hypotheses (ACH) has been suggested to be a method that can protect against confirmation bias in the context of intelligence analysis. In the current study, we aimed to determine whether ACH could counter confirmation bias in the reasoning with evidence in the context of criminal law proceedings. Law students (N = 191) received information about the ACH method or general information about biases. They were given a case vignette with a main suspect and a list of 24 questions, 6 of which they could ask about the case. Half of the questions related to incriminating information, whereas the other half related to exonerating information. Contrary to our expectations, participants in both conditions favoured questions relating to exonerating information and rated the exonerating evidence as being more important for their decision. Despite the lack of bias observed, it seems participants failed to properly apply the ACH method.     

Increased sensitivity to differentially diagnostic answers using familiar materials: Implications for confirmation bias

Researchers have recently pointed out that neither biased testing nor biased evaluation of hypotheses necessitates confirmation bias--defined here as systematic overconfidence in a focal hypothesis--but certain testing/evaluation combinations do. One such combination is (1) a tendency to ask about features that are either very likely or very unlikely under the focal hypothesis (extremity bias) and (2) a tendency to treat confirming and disconfirming answers as more similar in terms of their diagnosticity (or informativeness) than they really are. However, in previous research showing the second tendency, materials that are highly abstract and unfamiliar have been used. Two experiments demonstrated that using familiar materials led participants to distinguish much better between the differential diagnosticity of confirming and disconfirming answers. The conditions under which confirmation bias is a serious concern might be quite limited.     

Biased information search in homogeneous groups: confidence as a moderator for the effect of anticipated task requirements

When searching for information, groups that are homogeneous regarding their members' prediscussion decision preferences show a strong bias for information that supports rather than conflicts with the prevailing opinion (confirmation bias). The present research examined whether homogeneous groups blindly search for information confirming their beliefs irrespective of the anticipated task or whether they are sensitive to the usefulness of new information for this forthcoming task. Results of three experiments show that task sensitivity depends on the groups' confidence in the correctness of their decision: Moderately confident groups displayed a strong confirmation bias when they anticipated having to give reasons for their decision but showed a balanced information search or even a dis confirmation bias (i.e., predominately seeking conflicting information) when they anticipated having to refute counterarguments. In contrast, highly confident groups demonstrated a strong confirmation bias independent of the anticipated task requirements.     

判断与决策中的证实性偏差

证实性偏差是指个体在决策时, 倾向于有意或无意地寻找支持已有信念、预期或假设的信息和解释, 忽视可能与之不一致的信息和解释。目前, 研究者主要从肯定检验策略、认知失调理论以及错误规避三个方面解释证实性偏差的心理机制。证实性偏差还受到条件性参考框架、任务的抽象性、个体经验以及认知闭合的需要等因素的影响。虽然证实性偏差不能完全消除, 但是可以通过竞争性假设分析法和考虑对立面的方法降低其程度。未来的研究可以从证实性偏差的产生根源、研究范式、群体决策中的证实性偏差以及拓展应用研究这四个方面进行探讨。     

Biased Evaluation of Abstracts Depending on Topic and Conclusion: Further Evidence of a Confirmation Bias Within Scientific Psychology

The present paper investigated whether academic psychologists show a tendency to rate the quality and appropriateness of scientific studies more favorably when results and conclusions are consistent with their own prior beliefs (i.e., confirmation bias). In an online experiment, 711 psychologists completed a questionnaire (e.g., about their belief in astrology) and evaluated research that was presented in form of a short abstract in which 40 different behaviors (e.g., alcohol consumption, willingness to share money) have been tried to be predicted. The research to be evaluated varied on three dimensions which were all manipulated between subjects: (1) the predictors of the 40 behaviors (either Big Five or astrological factors), (2) the methodological quality of the study (low, medium, high), and (3) the results and subsequent conclusion of the study (confirmation or disconfirmation of the hypotheses). Factor-analyzed scores of participants’ ratings on 8 scales, resulting in 2 factors termed quality and appropriateness, served as dependent measures. The main result of the study is a two-way interaction: Psychologists tended to evaluate results qualitatively higher when they conformed to their own prior expectations, as in this case, when astrological hypotheses were disconfirmed.     

Strategies of rule discovery in an inference task

It has long been known that subjects in certain inference tasks will seek evidence which can confirm their present hypotheses, even in situations where disconfirmatory evidence could be more informative. We sought to alter this tendency in a series of experiments which employed a rule discovery task, the 2-4-6 problem first described by Wason. The first experiment instructionally modified subjects confirmatory tendencies. While a disconfirmatory strategy was easily induced, it did not lead to greater efficiency in discovering the rule. The second experiment introduced subjects to the possibility of disconfirmation only after they had developed a strongly held hypothesis through the use of confirmatory evidence. This manipulation also failed to alter the efficiency of rule discovery. In the third experiment, subjects were taught to use multiple hypotheses at each step, in the manner of Platt's “Strong Inference”. This operation actually worsened performance. Finally, in the fourth experiment, the structure of the problem was altered slightly by asking subjects to seek two interrelated rules. A dramatic increase in performance resulted, perhaps because information which in previous tasks was seen as merely erroneous could now be related to an alternative rule. The four studies have broad implications for the psychological study of inference processes in general, and for the study of scientific inference in particular.     

The “analysis of competing hypotheses” in intelligence analysis

The intelligence community uses “structured analytic techniques” to help analysts think critically and avoid cognitive bias. However, little evidence exists of how techniques are applied and whether they are effective. We examined the use of the analysis of competing hypotheses (ACH)—a technique designed to reduce “confirmation bias.” Fifty intelligence analysts were randomly assigned to use ACH or not when completing a hypothesis testing task that had probabilistic ground truth. Data on analysts' judgement processes and conclusions were collected using written protocols that were then coded for statistical analyses. We found that ACH‐trained analysts did not follow all of the steps of ACH. There was mixed evidence for ACH's ability to reduce confirmation bias, and we observed that ACH may increase judgement inconsistency and error. It may be prudent for the intelligence community to consider the conditions under which ACH would prove useful and to explore alternatives.     

The path or the goal? Decision vs. information focus in biased information seeking after preliminary decisions

Research on the phenomenon of selective exposure to information demonstrates that after preliminary or final decisions, people show a preference for supporting rather than conflicting information (confirmation bias). In this article, we examine conditions that increase or decrease distortions in the search for information. We report on four experiments indicating that the confirmation bias is influenced by whether people focus on their decision or on the presented pieces of information during the information search. Focusing on the decision, for example, because a reward for a correct decision is promised or simply because participants repeatedly think of it, increases the confirmation bias. On the other hand, if participants focus on the available pieces of information because they have to invest money in order to search for information or because they have to evaluate the individual pieces of information, the confirmation bias decreases. Implications for theoretical understanding and interventions for decision-making situations are discussed.     

A philosophical and empirical analysis of subjects' modes of inquiry in wason's 2-4-6 task

Investigations of hypothesis-testing behaviour typically conclude that subjects' methods are characterized by “confirmation bias.” However, these studies (a) relied exclusively upon Karl Popper's philosophy of science, (b) only described subjects' strategies via a falsificationist terminology, and (c) failed to determine subjects' precise intentions in the task situations. Alternative philosophies of science can be used to describe hitherto ignored aspects of rule discovery in Wason's (1960) 2-4-6 task as well as reinterpret findings from previous research. Using Wason's task, Experiment 1 adopted J. S. Mill's inductive methodology in order to assess better the extent of elimination in experimentation. While it was found that subjects did eliminate a large proportion of their hypotheses rather than merely confirm them, Mill's eliminative methods applied to this task failed to account for the entirety of subjects' behaviours. Experiment 2 examined subjects' methods in more depth by asking subjects during the task either to: (1) describe their procedures, (2) select from a list of methodology terms those that best characterized their methods, and (3) state on each learning trial their preferred hypotheses and their subjective assessments that those hypotheses were correct. Although subjects were generally unable to describe their methods of inquiry, they were able to typify them via the methodology terms as if their methods were tacitly held skills. Contrary to presumptions of previous research, analyses indicated that subjects were not testing particular hypotheses on every trial but were often examining possible instances of the rule “at random” or “different from ones examined” to that trial. It is also suggested that subjects' decisions to announce rules and their thematic lines of inquiry be given further consideration by researchers.     

Biased cognitive operations in anxiety: Accessibility of information or assignment of processing priorities?

There is considerable evidence that anxiety is associated with a cognitive bias favouring the processing of threat-related information. Bower's (1981) network model attributes this bias to the enhanced availability of mood congruent information from memory. However, certain experimental tasks do not reveal such a bias, when this effect is strongly predicted by the model. We note that all tasks which have demonstrated such mood congruent processing effects in anxious subjects share the requirement that these subjects must assign priorities to simultaneously available, and differentially valenced, alternative processing options. This feature has been consistently lacking in those paradigms we have found insensitive to the influence of anxiety. It is therefore suggested that anxiety is associated with the assignment of high processing priorities to threat-related options, rather than with the facilitated availability of threat-related information from memory. This proposal was experimentally tested using a lexical decision task, which is sensitive to the accessibility of information from memory, under conditions which either do or do not introduce the requirement to assign priorities to alternative processing options. The results indicate that the facilitated processing of threat related stimulus words, shown by generalised anxiety patients, does indeed appear to reflect a bias in the assignment of processing priorities, rather than the enhanced availability of this information from memory.     

Are there ��His�� and ��Her�� Types of Decisions? Exploring Gender Differences in the Confirmation Bias

Research on biased information seeking demonstrates that after decisions, people show a preference for supporting rather than conflicting information (confirmation bias). In a laboratory study (N?=?86 German undergraduates), we examined the interactive effects of different decision types and gender on the confirmation bias. Our study revealed that women showed less confirmation bias when the decision concerned themselves and their mate (interdependent decision) compared to a decision concerning only themselves (independent decision). In contrast, men showed less confirmation bias when they made an independent compared to an interdependent decision. Results were discussed in terms of self-construal differences between men and women leading to different motivations (defense vs. accuracy) during the information seeking depending on the decision type.     

Confirmation bias in sequential information search after preliminary decisions: an expansion of dissonance theoretical research on selective exposure to information

Research on selective exposure to information consistently shows that, after having made a decision, people prefer supporting over conflicting information. However, in all of these experiments participants were given an overview of all available pieces of information, selected them simultaneously, and did not process the requested information during the selection phase. In the present research the authors show that an even stronger preference for supporting information arises if information is presented and processed sequentially instead of simultaneously (Experiment 1), and they demonstrate that this stronger confirmation bias is due to sequential presentation and not to sequential processing of information (Experiment 2). The authors provide evidence that the increase in confirmation bias under sequential presentation is caused by heightened commitment due to the participants' increased focusing on their decision (Experiments 3 and 4).     

The Influence of Confirmation Bias on Memory and Source Monitoring

Two experiments were conducted to examine whether recognition memory for information and/or its source are influenced by confirmation bias. During Phase 1, subjects were shown a summary about the issue of gun control and asked to indicate a position on the issue. During Phase 2, 12 abstracts (Experiment 1) or social media posts (Experiment 2) were shown, one at a time. Posts in Experiment 2 were associated with either friends or strangers. Participants indicated whether they wanted to read a more extensive version of each abstract (Experiment 1) or post (Experiment 2). Phase 3 was the memory phase. Thirty-two abstract titles (Experiment 1) or posts (Experiment 2) were shown one at a time. Participants indicated yes or no, and whether they recognized the titles/posts from the last phase. Recognition memory for information that supported the participants' viewpoint was higher than that for opposing information.     

Accessing lexical ambiguities during sentence comprehension: Effects of frequency of meaning and contextual bias

Two hypotheses concerning the nature of lexical access, the exhaustive access and the terminating ordered search hypotheses, were examined in two separate studies using a crossmodal lexical priming task. In this task, subjects listened to sentences that were biased toward either the primary interpretation (a meaning occurring 75% or more of the time) or a secondary interpretation (a meaning occurring less than 25% of the time) of a lexical ambiguity that occurred in each sentence. Simultaneously, subjects made lexical decisions about visually presented words. Decisions to words related to both the primary and secondary meanings of the ambiguity were facilitated when presented immediately following occurrence of the ambiguity in the sentence. This effect held under each of the two biasing context conditions. However, when they were presented 1.5 sec following occurrence of the ambiguity, only visual words related to the contextually relevant meaning of the ambiguity were facilitated. These results support the exhaustive access hypothesis. It is argued that lexical access is an autonomous subsystem of the sentence comprehension routine in which all meanings of a word are momentarily accessed, regardless of the factors of contextual bias or bias associated with frequency of use.     

Information Integration Theory,Juror Bias,and Sentence Recommendations Captured Over Time in a Capital Trial

Initial juror verdicts have been shown to predict final verdicts, leading researchers to conclude that jurors seek confirmatory information during trial (confirmation bias) or distort information to fit pre‐existing biases (pre‐decisional distortion). However, Information Integration Theory suggests that individuals are not distorting/ignoring this information, and instead, information influences judgments in the direction of the message. The current study sought to test these competing theories in a juror setting. Mock jurors were presented with the sentencing phase of a capital trial and were asked to give sentence recommendations at eight different time points. Additionally, they were grouped by their pretrial bias as being pro‐defense, neutral, or pro‐prosecution. Results showed support for Information Integration Theory; although jurors' pretrial bias predicted final sentence, sentence recommendations were affected in the direction of the testimony presented throughout the trial (e.g., pro‐defense testimony lowered death penalty decisions across all groups). Implications and future directions are discussed. Copyright © 2015 John Wiley & Sons, Ltd.     

Sensitivity to alternatives in social hypothesis-testing

Past research has documented a hypothesis-testing strategy wherein evidence is sought to the extent that it is probable under the hypothesis. This strategy may yield nondiagnostic information and even biased confirmation of the hypothesis if the simultaneous probability of the evidence under the alternatives is disregarded. The results of three experiments demonstrated that hypothesis-testers were in fact sensitive to the probability of the evidence under the alternatives. In the first experiment, subjects tested a hypothesis under which two kinds of personal features, A-features and B-features, were highly probable. Subjects could test their hypothesis by selecting questions from a list of questions about A-features and B-features. The rerults showed that subjects' questions depended on the probability of the features under the alternative. Specifically, when the hypothesis shared A-features with the alternative, subjects preferred questions about B-features, but when the hypothesis shared B-features with the alternative, subjects preferred questions about A-features. Experiment 2 extended these findings to self-generated questions about a broader range of hypotheses and alternatives. Experiment 3 found that subjects who were provided with a specific alternative asked more diagnostic questions than subjects who were not provided with a specific alternative. Together, these results suggest that the process of generating and evaluating alternatives plays a crucial role in social hypothesis-testing and categorization.     

Conflict between incompetences and influence of a low-expertise source in hypothesis testing

In a 2–4–4–like reasoning task, 69 subjects tested hypotheses following exposure to a low-expertise source proposing an alternative hypothesis. Subjects compared self- and source's competence either independently or interdependently. Results show that interdependence leads subjects to assert self-validity and the source's invalidity, and to test hypotheses through confirmation. Independence produces a conflict between incompetences, i.e. doubt concerning self- and source's validity, leading to disconfirmatory testing.     

Sensible reasoning in two tasks: Rule discovery and hypothesis evaluation

The hypothesis testing skills of undergraduates were measured in two tasks: the 2-4-6 rule discovery task in which students generate and assess hypotheses, and a hypothesis evaluation task, which requires only the assessment of hypotheses. The results of Experiments 1 and 2 show that the students consistently employed a disconfirmation strategy when assessing hypotheses, but employed a counterfactual inference strategy when they also were required to generate the hypotheses. The results of Experiment 3 suggest that the selection of the hypothesis testing strategy reflected a balance between the logical requirements of the task and the desirability of possible outcomes. Taken together, the findings support a more consistent picture of human rationality across tasks, and suggest alternatives to accounts of confirmation bias.