Information Processing and Constraint Satisfaction in Wason’s Selection Task

In Wason’s Selection Task, subjects: (i) process information from the instructions and build a mental representation of the problem, then: (ii) select a course of action to solve the problem,under the constraints imposed by the instructions. We analyze both aspects as part of a constraint satisfaction problem without assuming Wason’s ‘logical’ solution to be the correct one. We show that outcome of step (i) may induce mutually inconsistent constraints, causing subjects to select at step (ii) solutions that violate some of them. Our analysis explains why inconsistent constraints are less likely disrupt non-abstract (or “thematic”) versions of the tasks, but unlike Bayesians does not posit different mechanisms in abstract and thematic variants. We then assess the logicality of the task, and conclude on cognitive tasks as coordination problem

A "Game of Like" : Online Social Network Sharing As Strategic Interaction

We argue that behavioral science models of online content-sharing overlook the role of strategic interactions between users. Borrowing from accuracy-nudges studies decision-theoretic models, we propose a basic game model and explore special cases with idealized parameter settings to identify refinements necessary to capture real-world online social network behavior. Anticipating those refinements, we sketch a strategic analysis of content amplification and draw a connection between Keynes's beauty contest analogy and recent social-epistemological work on echo chambers. We conclude on the model's prospects from analytical and empirical perspectives.Comment: In Proceedings TARK 2023, arXiv:2307.0400

Remote Toehold: A Mechanism for Flexible Control of DNA Hybridization Kinetics

Hybridization of DNA strands can be used to build molecular devices, and control of the kinetics of DNA hybridization is a crucial element in the design and construction of functional and autonomous devices. Toehold-mediated strand displacement has proved to be a powerful mechanism that allows programmable control of DNA hybridization. So far, attempts to control hybridization kinetics have mainly focused on the length and binding strength of toehold sequences. Here we show that insertion of a spacer between the toehold and displacement domains provides additional control: modulation of the nature and length of the spacer can be used to control strand-displacement rates over at least 3 orders of magnitude. We apply this mechanism to operate displacement reactions in potentially useful kinetic regimes: the kinetic proofreading and concentration-robust regimes

The interrogative model of inquiry and inquiry learning

Hakkarainen and Sintonen (2002) praise the descriptive adequacy of Hintikka's Interrogative Model of Inquiry (imi) to describe children's practices in an inquiry-based learning context. They further propose to use the imi as a starting point for developing new pedagogical methods and designing new didactic tools. We assess this proposal in the light of the formal results that in the imi characterize interrogative learning strategies. We nd that these results actually reveal a deep methodological issue for inquiry-based learning, namely that educators cannot guarantee that learners will successfully acquire a content, without limiting learner's autonomy, and that a trade-off between success and autonomy is unavoidable. As a by-product of our argument, we obtain a logical characterization of serendipity

Taking Problem-Solving Seriously

Instructions in Wason’s Selection Task underdetermine empirical subjects’ representation of the underlying problem, and its admissible solutions. We model the Selection Task as an (ambiguous) interrogative learning problem, and reasoning to solutions as: (a) selection of a representation of the problem; and: (b) strategic planning from that representation. We argue that recovering Wason’s ‘normative’ selection is possible only if both stages are constrained further than they are by Wason’s formulation. We conclude comparing our model with other explanatory models, w.r.t. to empirical adequacy, and modeling of bounded rationality

Semantic Games for Algorithmic Players

We describe a class of semantic extensive entailment game (eeg) with algorithmic players, related to game-theoretic semantics (gts), and generalized to classical first-order semantic entailment. Players have preferences for parsimonious spending of computational resources, and compute partial strategies, under qualitative uncertainty about future histories. We prove the existence of local preferences for moves, and strategic fixpoints, that allow to map eeg game-tree to the building rules and closure rules of Smullyan's semantic tableaux (st). We also exhibit a strategy profile that solves the fixpoint selection problem, and can be mapped to systematic constructions of semantic trees, yielding a completeness result by translation. We conclude on possible generalizations of our games

Model for acoustic induced aluminum combustion fluctuations in solid rocket motors

Combustion of aluminum droplets released by the solid propellant is widely used to increase the thrust in solid rocket motors. The combustion dynamics of the released droplet cloud in the unsteady flow is however susceptible to trigger thermoacoustic instabilities. A theoretical analysis is conducted to determine the heat release rate fluctuations produced by the burning droplet cloud for small acoustic disturbances. Two contributions to heat release fluctuations are identified. The first originates from fluctuations of the evaporation rate due to the oscillating flow around the droplets. This leads to local fluctuations of the volumetric rate of heat release within the droplet cloud. The second one originates from the motion of the boundary of the burning droplet cloud at the end of the combustion process. This motion is due to droplet lifetime oscillations leading to an additional source of heat release disturbances. Both contributions to heat release disturbances take place within the acoustic boundary layer along the solid propellant surface. Quasi-steady models for the response of the droplet diameter fluctuations and droplet velocity fluctuations are derived. Combined with a model for the gas velocity fluctuations within the acoustic boundary layer they lead to expressions for the resulting heat release rate disturbances within the droplet cloud and at its boundary. Results are compared to a previous low order model and to numerical flow simulations. It is shown that the new model leads to close agreement with simulations over the entire flow. The derived expressions yield a better understanding on heat release disturbances and can be used to predict the linear stability of a solid rocket motor at reduced computational costs

Development of a regional-scale library of near infrared reflectance soil spectra for alternative assessment of soil characteristics in Southern Belgium

In Walloon Region (Southern Belgium), five routine soil laboratories are grouped within a network promoting a better quality in analysis (www.requasud.be). The harmonization of protocols as well as methodological or technical prospective are realized under scientifically supervision of our research laboratory. In this context, a study was conducted to evaluate the ability of the NIRS to predict some soil properties: CEC, TOC, TN and clay content. The initial models were elaborated upon local PLS regression on set of 1 300 soil samples. The local PLS calibration used allows an accurate prediction of the soil properties and precision of NIRS technique is comparable to reference analytical metho