Case-based methods and agent-based modelling: bridging the divide to leverage their combined strengths

Two leading camps for studying social complexity are case-based methods (CBM) and agent-based modelling (ABM). Despite the potential epistemological links between ‘cases’ and ‘agents,’ neither camp has leveraged their combined strengths. A bridge can be built, however, by drawing on Abbott’s insight that ‘agents are cases doing things’, Byrne’s suggestion that ‘cases are complex systems with agency’, and by viewing CBM and ABM within the broader trend towards computational modelling of cases. To demonstrate the utility of this bridge, we describe how CBM can utilise ABM to identify case-based trends; explore the interactions and collective behaviour of cases; and study different scenarios. We also describe how ABM can utilise CBM to identify agent types; construct agent behaviour rules; and link these to outcomes to calibrate and validate model results. To further demonstrate the bridge, we review a public health study that made initial steps in combining CBM and ABM.     

Can we predict device use? An investigation into mobile device use in surveys

In this study, we investigate whether mobile device use in surveys can be predicted. We aim to identify possible motives for device use and build a model by drawing on theory from technology acceptance research and survey research. We then test this model with a Structural Equation Modeling approach using data of seven waves of the GESIS panel. We test whether our theoretical model fits the data by focusing on measures of fit, and by studying the standardized effects of the model. Results reveal that intention to use a particular device can predict actual use quite well. Ease of smartphone use is the most meaningful variable: if people use a smartphone for specific tasks, their intention to use a smartphone for survey completion is also more likely. In conclusion, investing in ease of use of mobile survey completion could encourage respondents to use mobile devices. This can foremost be established by building well-designed surveys for mobile devices.     

The association of infant crying,feeding, and sleeping problems and inhibitory control with attention regulation at school age

Regulatory problems in infancy and toddlerhood have previously been associated with an increased risk of developing attention problems in childhood. We hypothesized that early regulatory problems are associated with attention problems via reduced inhibitory control. This prospective study assessed 1,459 children from birth to 8 years. Crying, feeding, and sleeping problems were assessed at 5 and 20 months via parent interviews and neurological examinations. At 20 months, inhibitory control was tested with a behavioral (snack delay) task. Attention regulation was assessed at 6 and 8 years using multiple instruments and informants. Detrimental effects of crying, feeding, and sleeping problems on attention regulation were partly mediated by children's ability to inhibit unwanted behaviors (β = ?0.04, p = 0.013). Accounting for cognition diminished this indirect effect (β = ?0.01, p = 0.209). Instead, the effects of crying, feeding, and sleeping problems on attention regulation were fully mediated by children's cognitive functioning (β = ?0.10, p < 0.001). These results support that inhibitory control abilities partly mediate effects of crying, feeding, and sleeping problems. However, these effects may be accounted for by children's general cognitive abilities. Early regulatory problems may set infants on a course of under control of behavior into school age, and such trajectories are highly associated with general cognitive development.     

EVALUATING ECONOMICS RESEARCH IN EUROPE: AN INTRODUCTION

This paper introduces a symposium of EEA‐funded studies that evaluate economics research in Europe. The paper considers some general issues in evaluations, paying special attention to the problem of selecting journal weights, and notes some special features of the individual studies. Despite their very different approaches, the same group of institutions tend to appear at the top of all lists, though individual ranks are sensitive to the choice of more or less elitist journal weights. All the studies show that the gap between economics research in Europe and the United States is narrowing, but remains very wide. (JEL: A10, J44)     

A Bayesian piecewise exponential phase II design for monitoring a time-to-event endpoint

A robust Bayesian design is presented for a single-arm phase II trial with an early stopping rule to monitor a time to event endpoint. The assumed model is a piecewise exponential distribution with non-informative gamma priors on the hazard parameters in subintervals of a fixed follow up interval. As an additional comparator, we also define and evaluate a version of the design based on an assumed Weibull distribution. Except for the assumed models, the piecewise exponential and Weibull model based designs are identical to an established design that assumes an exponential event time distribution with an inverse gamma prior on the mean event time. The three designs are compared by simulation under several log-logistic and Weibull distributions having different shape parameters, and for different monitoring schedules. The simulations show that, compared to the exponential inverse gamma model based design, the piecewise exponential design has substantially better performance, with much higher probabilities of correctly stopping the trial early, and shorter and less variable trial duration, when the assumed median event time is unacceptably low. Compared to the Weibull model based design, the piecewise exponential design does a much better job of maintaining small incorrect stopping probabilities in cases where the true median survival time is desirably large.     

对综合类文化期刊“一稿多投”现象的理性分析

本文试图从作者队伍、刊物自身机制、市场经济学、市场传播学以及著作权法等方面入手,对“一稿多投”这种“不甚光彩”的社会灰色现象,进行一些力图客观公正的理性分析,并对刊物今后怎样做才能真正杜绝“一稿多投”现象的产生,提出了一些自己的看法。     

The Theory of Global Games on Test: Experimental Analysis of Coordination Games with Public and Private Information

The theory of global games has shown that coordination games with multiple equilibria may have a unique equilibrium if certain parameters of the payoff function are private information instead of common knowledge. We report the results of an experiment designed to test the predictions of this theory. Comparing sessions with common and private information, we observe only small differences in behavior. For common information, subjects coordinate on threshold strategies that deviate from the global game solution towards the payoff‐dominant equilibrium. For private information, thresholds are closer to the global game solution than for common information. Variations in the payoff function affect behavior as predicted by comparative statics of the global game solution. Predictability of coordination points is about the same for both information conditions.     

How Believing in Ourselves Increases Risk Taking: Perceived Self-Efficacy and Opportunity Recognition

What effect does positive and negative feedback about past risk taking have on the future risk taking of decision makers? The results of an experimental study show that subjects who are led to believe they are very competent at decision making see more opportunities in a risky choice and take more risks. Those who are led to believe they are not very competent see more threats and take fewer risks. The feelings of self-competence and self-confidence on one task did not generalize to a similar task. Perception of opportunities was unexpectedly not related to the perception of threats. As executives bring their personal perceptual biases to firm decision making, our results identify a serious built-in bias in SWOT analysis (the analysis of firms' strengths and weaknesses as related to potential opportunities and threats). Executives who believe that they and their firm are very competent will take more risks and vice versa. Our results also provide evidence that the perceived likelihood of an event depends on whether the event is a loss or a gain. Human decision making is subject to the general bias that outcome expectations are not independent of outcome valuations.