Contingency learning tracks with stimulus-response proportion no evidence of misprediction costs

We investigate the processes involved in human contingency learning using the color-word contingency learning paradigm. In this task, participants respond to the print color of neutral words. Each word is frequently presented in one color. Results show that participants respond faster and more accurately to words presented in their expected color. In Experiment 1, we observed better performance for high-relative to medium-frequency word-color pairs, and for medium-relative to low-frequency pairs. Within the medium-frequency condition, it did not matter whether the word was predictive of a currently-unpresented color, or the color was predictive of a currently-unpresented word. We conclude that a given word facilitates each potential response proportional to how often they co-occurred. In contrast, there was no evidence for costs associated with violations of high-frequency expectancies. Experiment 2 further introduced a novel word baseline condition, which also provided no evidence for competition between retrieved responses

Phase stacking diagram of colloidal mixtures under gravity

The observation of stacks of distinct layers in a colloidal or liquid mixture in sedimentation-diffusion equilibrium is a striking consequence of bulk phase separation. Drawing quantitative conclusions about the phase diagram is, however, very delicate. Here we introduce the Legendre transform of the chemical potential representation of the bulk phase diagram to obtain a unique stacking diagram of all possible stacks under gravity. Simple bulk phase diagrams generically lead to complex stacking diagrams. We apply the theory to a binary hard core platelet mixture with only two-phase bulk coexistence, and find that the stacking diagram contains six types of stacks with up to four distinct layers. These results can be tested experimentally in colloidal platelet mixtures. In general, an extended Gibbs phase rule determines the maximum number of sedimented layers to be $3+2(n_b-1)+n_i$, where $n_b$ is the number of binodals and $n_i$ is the number of their inflection points

Introduction: unmarried and unknown: urban men and women in the low countries since the early modern period

This essay introduces a special issue on The Lure of the City that examines the attraction of towns to unmarried men and women in the Low Countries during the early modern period and the nineteenth century. The issue has the relation between singles and cities as its main focus. Singles were present in disproportionately large numbers in urban areas, but the question is why? This essay sets out the historiographical framework for the contributions in the issue, discusses the sources and methodologies used, and provides a brief overview of the evolution of singleness in the Low Countries. The contributions all demonstrate the relevance of a comparative approach. It is revealed that towns and cities not only attracted but also created singles, that they offered different opportunities for different groups of unmarried people and that they affected men and women differently. Finally, it appears that not every town and city was attractive to men and women without a spouse