An experiment was conducted to test the effectiveness of brief instruction in information structuring (i.e., representing and integrating information) for improving the coherence of probability judgments and binary choices among intelligence analysts. Forty-three analysts were presented with comparable sets of Bayesian judgment problems before and immediately after instruction. After instruction, analysts’ probability judgments were more coherent (i.e., more additive and compliant with Bayes theorem). Instruction also improved the coherence of binary choices regarding category membership: after instruction, subjects were more likely (...) to invariably choose the category to which they assigned the higher probability of a target’s membership. The research provides a rare example of evidence-based validation of effectiveness in instruction to improve the statistical assessment skills of intelligence analysts. Such instruction could also be used to improve the assessment quality of other types of experts who are required to integrate statistical information or make probabilistic assessments. (shrink)

Psychology of communication must do everything is possible to promote an adequate perception of risk. This is particularly true when it comes to transmitting statistical and probabilistic data to an audience of non-experts, inevitably conditioning their perception of risk. Data are all available, but subjects are able to understand them in the specific meanings proper to a specialized language, only if they are adequately transmitted. And we find these phenomena in the difficulty in representing the trend of, for instance, Covid-19 (...) contagion, based on probability of contagion and mortality. In general, then, when we communicate scientific terms or data we should re-introduce the psychological aspects which characterize communication. The nudging strategies can be considered as a prototype of approach to overcome risky behaviours, which takes into account the cognitive characteristics of the human system. This strategy acts on different levels, using implicit factors, bypassing defensive attitudes and exploiting adaptive inferential processes, without overloading the cognitive system. But from a communicative point of view, nudge, as well as any other type of intervention, is not a general ‘recipe. The acceptance of the suggestion, the effectiveness of the nudging implies the congruity with the system that receives it: the “way of reasoning”, and its implicit layer has to be taken into account. The right combination of the source, the adopted message and the decisional setting could improve the efficacy of the public policies. (shrink)

The mentioning of error-possibilities makes us less likely to ascribe knowledge. This paper offers a novel psychological account of this data. The account appeals to “subadditivity,” a well-known psychological tendency to judge possibilities as more likely when they are disjunctively described.

Stochastic forecasts in complex environments can benefit from combining the estimates of large groups of forecasters (“judges”). But aggregating multiple opinions faces several challenges. First, human judges are notoriously incoherent when their forecasts involve logically complex events. Second, individual judges may have specialized knowledge, so different judges may produce forecasts for different events. Third, the credibility of individual judges might vary, and one would like to pay greater attention to more trustworthy forecasts. These considerations limit the value of simple aggregation (...) methods like linear averaging. In this paper, a new algorithm is proposed for combining probabilistic assessments from a large pool of judges. Two measures of a judge’s likely credibility are introduced and used in the algorithm to determine the judge’s weight in aggregation. The algorithm was tested on a data set of nearly half a million probability estimates of events related to the 2008 U.S. presidential election (∼ 16000 judges). (shrink)