James M Yearsley

Welcome to my Personal Website!

Feel free to have a poke around. You can read some information about the research I do, download my CV and find out how to contact me at Vanderbilt. There are also some specific resources relating to one of my research directions that you can browse.

Background

I have a background in theoretical physics, with a PhD from Imperial College London and post doc experience at the University of Cambridge. I moved to cognitive science to work on physics inspired models of cognition, particularly models of judgment and decision making based on the mathematics of quantum theory. More generally, I am interested in the way particular cognitive models might either be derived from underlying neural behaviour, or deduced as specific instances of a more general information processing framework.

Research Interests

Causal Reasoning

I’m interested in the way in which decision makers reason about the causal relations between events. This sort of reasoning is crucial to making sense of the world around us, but can also prove very complex when we are faced with questions such as, to what extent does smoking ’cause’ lung cancer, or can we say that climate change ’causes’ droughts?

I am particularly interested in the extent to which human decision makers follow normative standards when reasoning about causal relations. Do we reason rationally about causes and effects? and how is this related to the sorts of mental representations we form about events?

Quantum Models of Cognition and Decision

A major research interest of mine is in building and testing so-called ‘quantum’ models of decision. These are models based on a theory of probability different from classical probability, and as such they can naturally incorporate order effects and context effects in decision making, and more generally the constructive nature of judgments.

Many of my other research projects involve some element of quantum modelling, but I have a particular interest in two question; first, can we come up with definitive tests of quantum vs classical models of cognition? and second, why do certain types of decision making seem to be described so well by these quantum models?

For more information on quantum cognition see this page.

Similarity Judgments

In the past I have work on models of human similarity judgments, looking particularly at ways in which people violate the predictions of distance-based models of similarity. These effects were first pointed out in a seminal paper by Tversky (1977). They include violations of symmetry, so that [latex] Sim(A,B)\neq Sim(B,A)[/latex] and a context effect known as ‘diagnosticity’ where the similarity between two items can depend on the presence of context items.

My work involved trying to build models of these effects using quantum theory.

Ethical/Moral Decision Making

I have worked in the past on decision making in ethical dilemmas, such as the famous trolley problem. Previous research has shown that people can be primed to respond in a more or less ‘ethical’ way by reminding them of past experiences. An interesting question is whether the two different ways of evaluating this sort of problem (utilitarian or rule-based/deontological) represent different modes of thinking and what, if anything, this has to do with gender differences in responses.