Evolutionary modeling of behaviour in sociobiology and psychology

有两个项目，都是对行为的进化研究。第一个属于生物学，涉及我们在试图理解生物体行为时使用的理论结构的性质和结构。第二种方法更多地属于心理学和经济学，既有理论成分，也有实验成分。它使用了一个新的“信号”版本的最后通牒游戏，以帮助我们理解人类在经济决策中的行为。******项目1继续我正在进行的关于分析社会行为的包容适应度（IF）方法的研究。这涉及到行为者的行为影响亲属的适合度的情况，长期以来人们已经认识到，选择的力量应该改变行为，以考虑到这种影响。Hamilton （F8）表明，进化应该最大化这些适应度效应的简单加权（通过亲缘关系）总和。这使得IF效应简单而直观（帮助你的邻居与他们的“亲密程度”成比例），并且在一系列广泛的假设（主要是弱选择）下，它的预测与更详细的遗传模型相匹配。******我过去的工作一直是讨论中频模型的预测，并建立与其他标准适应度测量（如固定概率）的精确等效结果。在这项工作中，我发现了许多优雅的结构结果。这包括进化稳定性的两个一般条件；前者适用于所有同质种群结构（F25），后者适用于有限和无限种群的协同（非加性）适应度效应（CCV10）。当然，中频公式对于发现这些简单条件是至关重要的。******在接下来的五年里，我将继续这项工作，寻求简单的一般结果，专注于阶级结构的人口和非加性适应度效应。******在项目2的最后通牒博弈中，参与人1向参与人2提出如何分配可用资源的建议，但这只有在参与人2接受的情况下才会实施；否则双方都一无所获。实验表明，在这场博弈中，人类比纳什均衡所预测的要慷慨得多。在我们的变体中，参与人2提出了一个预先要求：“我将接受不少于x的条件”，然而，他并没有被迫遵守这个要求。这类似于雄性黑鹂翅膀上的红色斑块，似乎表明了良好的父权关系，但可能是不诚实的。这个可能是空的需求如何影响参与人1的出价？从生物学研究中我们知道，这种质量信号除非给信号者带来成本，否则是不起作用的。因此，我们引入并调查了一个成本，这个成本与需求和“最小接受”之间的差额成正比，低于这个差额，报价就会失败。******这个项目激发了我的研究生的兴趣，我将能够让他们参与模型构建以及实地工作。

There are two projects, both evolutionary studies of behaviour. The first belongs to biology and concerns the nature and structure of the theoretical constructs we use in our attempt to understand behaviour of living organisms. The second belongs more to psychology and economics and has both theoretical and experimental components. It uses a new “signal” version of the much studied ultimatum game to help us understand human behaviour in economic decision making. ******Project 1 continues my ongoing study of the inclusive fitness (IF) method for analyzing social behaviour. This concerns situations in which the behaviour of an actor affects the fitness of relatives and it has been realized for a long time that selective forces should modify behaviour to take account of such effects. Hamilton (F8) showed that evolution should maximize a simple weighted (by relatedness) sum of these fitness effects. This constructthe IF effectis simple and intuitive (help your neighbours in proportion to their “closeness”) and under a wide set of assumptions (principally weak selection) its predictions match those of more-detailed genetic models. ******My past work has been to discuss the predictions of IF models and establish precise equivalence results to other standard measures of fitness such as fixation probability. In this work I have discovered many elegant structural results. These include two general conditions for evolutionary stability; the first applies to all homogeneous population structures (F25) and the second to synergistic (non-additive) fitness effects in both finite and infinite populations (CCV10). It is certainly the case that the IF formulation was crucial to the discovery of these simple conditions.******Over the next five years I will continue this work, seeking simple general results, focusing on class-structured populations and non-additive fitness effects. ******In the ultimatum game of Project 2, player 1 makes an offer to player 2 of how to split an available resource, but that is implemented only if player 2 accepts; otherwise both get nothing. Experiments show that humans play this game much more generously than the Nash equilibrium would predict. In our variation, player 2 makes an up-front demand: “I will accept no less than x,” which, however, he is not compelled to adhere to. This is analogous to the red patch on a male blackbird wing that appears to signal good paternity but might be dishonest. How is this, possibly empty, demand to affect player 1's offer? It is known from biological studies that such signals of quality do not work unless they exact a cost on the signaler and for this reason we introduce and investigate a cost taken to be proportional to the difference between the demand and the “minaccept” below which the offer will fail. ******This project has inspired the interest of my grad students and I will be able to involve them in the model building as well as the field work.