Two friends and collaborators, Katya Tentori (Trento) and Matteo Colombo (Tilburg), are going to present research work I’ve been involved in at the next International Conference on Thinking (Brown University, Providence, RI, August 4-6). Abstracts are below. (Sad that I’ll be missing the event, which will be truly remarkable: have a look yourself at the complete program!)
Katya Tentori, Andrea Passerini, and Vincenzo Crupi
Judging forecasting accuracy: How human intuitions meet theoretical models
Abstract. Most of the scoring rules that have been discussed and defended in the literature are not ordinally equivalent, with the consequence that, after the very same outcome has materialized, a forecast X can be evaluated as more accurate than Y according to one model but less accurate according to another. A question that naturally arises is therefore which of these models better captures people’s intuitive assessment of forecasting accuracy. To answer this question, we developed a new experimental paradigm for eliciting ordinal judgments of accuracy concerning pairs of forecasts for which various combinations of associations/dissociations between the Quadratic, Logarithmic, and Spherical scoring rules are obtained. We found that, overall, the Logarithmic model is the best predictor of people’s accuracy judgments, but also that there are cases in which these judgments – although normatively sound – systematically depart from what is expected by all the models. These results represent an empirical evaluation of the descriptive adequacy of the three most popular scoring rules and offer insights for the development of new formal models that might favour a more natural elicitation of truthful and informative beliefs from human forecasters.
Matteo Colombo, Jun Lai, and Vincenzo Crupi
Sleeping Beauty goes to the lab: The psychology of self-locating evidence
Abstract. The Sleeping Beauty Problem is a challenging puzzle in probabilistic reasoning, which has attracted enormous attention and continues to produce ongoing debate. The problem goes as follows. Suppose that some researchers are going to put you to sleep. During the two days that your sleep will last, they will briefly wake you up either once or twice, depending on the toss of a fair coin (Heads: once; Tails: twice). After each waking, they will put you back to sleep with a drug that makes you forget that waking. When you are first awakened, to what degree ought you believe that the outcome of the coin toss is Heads? The two candidate answers are 1/2 and 1/3, the proponents of which are known as halfers and thirders. The present study examines for the first time the descriptive adequacy of both halfers’ and thirders’ answers. Our results show that naïve reasoning does not simply fit either. In particular, they suggest that any psychologically adequate analysis of the Sleeping Beauty Problem should take account that the impact of self-locating information on probabilistic reasoning is systematically discounteed.