Algorithmic Bayesian Persuasion

Persuasion, defined as the act of exploiting an informational advantage in order to effect the decisions of others, is ubiquitous. Indeed, persuasive communication has been estimated to account for almost a third of all economic activity in the US. This paper examines persuasion through a computational lens, focusing on what is perhaps the most basic and fundamental model in this space: the celebrated Bayesian persuasion model of Kamenica and Gentzkow. Here there are two players, a sender and a receiver. The receiver must take one of a number of actions with a-priori unknown payoff, and the sender has access to additional information regarding the payoffs. The sender can commit to revealing a noisy signal regarding the realization of the payoffs of various actions, and would like to do so as to maximize her own payoff assuming a perfectly rational receiver. We examine the sender's optimization task in three of the most natural input models for this problem, and essentially pin down its computational complexity in each. When the payoff distributions of the different actions are i.i.d. and given explicitly, we exhibit a polynomial-time (exact) algorithm, and a "simple" $(1-1/e)$-approximation algorithm. Our optimal scheme for the i.i.d. setting involves an analogy to auction theory, and makes use of Border's characterization of the space of reduced-forms for single-item auctions. When action payoffs are independent but non-identical with marginal distributions given explicitly, we show that it is #P-hard to compute the optimal expected sender utility. Finally, we consider a general (possibly correlated) joint distribution of action payoffs presented by a black box sampling oracle, and exhibit a fully polynomial-time approximation scheme (FPTAS) with a bi-criteria guarantee. We show that this result is the best possible in the black-box model for information-theoretic reasons

Theoretical Modeling for Curious Leadership and Instrument Development and Validation for Measuring Curious Leader Capacity

When curious, we admit we do not know. With the contemporary workplace emerging through increased complexity, leaders are compelled to shift mindsets and practices from more traditional methods to those more in service to the uncertainty of the day. The purpose of this mixed-methods study was to generate an integrated theoretical framework for curious leadership, a validated scale for its measurement, and practical methods for engaging differently in the context and practice of leading. Drawing from the literature review of relational leadership, adaptive leadership, complexity leadership, growth mindsets, and curious behavior, and from my practice, 12 sub-constructs were identified as possible scale components of curious leader behavior. A mixed-methods approach was taken with three differently composed focus groups who reviewed the 12 sub-constructs and honed them to four based on their intersections in Phase 1 of the study. In Phase 2, a survey was thereby developed identifying 66 items for further subsequent appraisal. A finalized survey was undertaken with 274 respondents. From principal and confirmatory factor analysis, four sub-scales were eventually identified: Encourage Emergence, Enable Openness, Engage Experiments, and Honor Humanness resulting in the development of the Gick Curious Leader Capacity Scale. The scale\u27s application and future implications for research and practice are discussed. This dissertation is available in open access at AURA, https://aura.antioch.edu/, and OhioLINK ETD Center, https://etd.ohiolink.edu

Dificultades para codificar, relacionar y categorizar problemas verbales algebraicos: dos estudios con estudiantes de secundaria y profesores en formación

En resolución de problemas verbales por transferencia, la activación de problemas ya conocidos que sirvan de guía, depende de las analogías percibidas entre éstos y el problema a resolver. Se desarrollan dos estudios relacionados para analizar en qué características se basan los estudiantes para codificar problemas y detectar sus analogías, en tareas de categorización (sorting). Se utilizaron técnicas cuantitativas y cualitativas combinadas. Primero se analizó cómo los estudiantes de secundaria son influidos por diferentes variables características de problemas de ciencias. Una gran proporción de sujetos no fue capaz de percibir las analogías y diferencias adecuadas entre problemas. El segundo estudio trató de avanzar una explicación de estos resultados. El nivel académico y la familiaridad con las temáticas fueron factores significativos, pero los futuros profesores participantes mostraron demasiadas dificultades, alertando sobre la conveniencia de revisar algunos supuestos instruccionales habituales

The diffusion of water and aviation fuel in polysulphide sealants

The diffusion and permeation of aviation fuel (Avtur) and water in commercial and 'model' polysulphide sealants have been studied using simple gravimetric techniques. For Avtur, the mass uptake behaviour is explicable in terms of normal, Fickian diffusion, and the diffusion coefficient determined has been found to be independent of the experimental method and concentration of the liquid. Water, however, exhibits anomalous diffusion behaviour. Mass uptake by the polysulphides is high and equilibrium is not reached after several months. There is no correlation between the results of permeation, absorption and desorption experiments except at low water concentration. These anomalies have been explained in terms of the formation of water droplets within the rubber. This study shows that the amount of water absorbed is dependent upon the amount and nature of the curing agent residues. The results have been analysed in terms of the osmotic and water vapour pressure and two equations have been derived which satisfactorily predict the amount of water absorbed at equilibrium. It has been shown that the effect of the water droplets on permeation is negligible, and hence the diffusion coefficient found is a measure of the true rate of diffusion. In contrast, the effect of the droplets on mass uptake experiments is large and the apparent overall diffusion rate is greatly reduced. The apparent diffusion coefficient found is dependent upon the water concentration and the concentration of the water-soluble impurities. An equation has been derived showing the relationship between these variables. The results of this work show that the elastic strength of the rubber has negligible effect in determining the water uptake at equilibrium and the apparent diffusion coefficient. However, deterioration in adhesive and cohesive strength occurs with water uptake. At high uptake some of this loss is irreversible. The deterioration in properties is mainly due to breakage of weak physical bonds and plasticisation effects

Fostering students’ evaluation behaviour while searching the internet

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Learners in a Changing Learning Landscape: Reflections from an Instructional Design Perspective

Van Merriënboer, J. J. G., & Stoyanov, S. (2008). Learners in a changing learning landscape: Reflections from an instructional design perspective. In J. Visser & M. Visser-Valfrey (Eds.), Learners in a changing learning landscape: Reflections from a dialogue on new roles and expectations (pp. 69-90). Dordrecht, The Netherlands: Springer.Both learners and teachers find themselves in a learning landscape that is rapidly changing, along with fast societal and technological developments. This paper discusses the new learning landscape from an instructional design perspective. First, with regard to what is learned, people more than ever need flexible problem-solving and reasoning skills allowing them to deal with new, unfamiliar problem situations in their professional and everyday life. Second, with regard to the context in which learning takes place, learning in technology-rich, informal and professional 24/7 settings is becoming general practice. And third, with regard to the learners themselves, they can more often be characterized as lifelong learners who are mature, bring relevant prior knowledge, and have very heterogeneous expectations and perceptions of learning. High-quality instructional design research should focus on the question which instructional methods and media-method combinations are effective, efficient and appealing in this new learning landscape. Some innovative instructional methods that meet this requirement are discussed

Priming Analogical Reasoning with False Memories

Like true memories, false memories are capable of priming answers to insight-based problems. Recent research has attempted to extend this paradigm to more advanced problem-solving tasks, including those involving verbal analogical reasoning. However, these experiments are constrained inasmuch as problem solutions could be generated via spreading activation mechanisms (much like false memories themselves) rather than using complex reasoning processes. In three experiments we examined false memory priming of complex analogical reasoning tasks in the absence of simple semantic associations. In Experiment 1, we demonstrated the robustness of false memory priming in analogical reasoning when backward associative strength among the problem terms was eliminated. In Experiments 2a and 2b, we extended these findings by demonstrating priming on newly created homonym analogies that can only be solved by inhibiting semantic associations within the analogy. Overall, the findings of the present experiments provide evidence that the efficacy of false memory priming extends to complex analogical reasoning problems

The Effects of Previous Misestimation of Task Duration on Estimating Future Task Duration

It is a common time management problem that people underestimate the duration of tasks, which has been termed the "planning fallacy." To overcome this, it has been suggested that people should be informed about how long they previously worked on the same task. This study, however, tests whether previous misestimation also affects the duration estimation of a novel task, even if the feedback is only self-generated. To test this, two groups of participants performed two unrelated, laboratory-based tasks in succession. Learning was manipulated by permitting only the experimental group to retrospectively estimate the duration of the first task before predicting the duration of the second task. Results showed that the experimental group underestimated the duration of the second task less than the control group, which indicates a general kind of learning from previous misestimation. The findings imply that people could be trained to carefully observe how much they misestimate task duration in order to stimulate learning. The findings are discussed in relation to the anchoring account of task duration misestimation and the memory-bias account of the planning fallacy. © 2014 Springer Science+Business Media New York