Accumulating to choose, but accumulating what? Drift diffusion modelling of economic preference

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Imagine choosing between an apple and some chocolate. In one instant you will be thinking about the lovely, crunchy apple. The next you are thinking about the smooth, indulgent chocolate. Your attention will dart back and forth between the apple and the chocolate until you make your mind up. This research is about exactly what is happening, at each instant, as you deliberate and choose. We will combine laboratory experiments (detailed in the Case for Support) and translational field experiments with real consumers making real choices (with our industry collaborators, detailed in the Pathways to Impact). Using eye-tracking technology, we will record millisecond-by-millisecond where people are looking as they choose. This will allow us to build an explanation of the link between attention and choice.Psychology, Neuroscience, and Economics have developed a first-generation model based on some key findings. When someone is choosing they take time to deliberate and shift their attention back and forth repeatedly. We now know that people are likely to look more at the option they ultimately choose and that if we intervene to make people look more at one option they are more likely to choose it. This has led to the development of drift diffusion models. Although complicated, these models instantiate the following idea: While an individual is looking at a specific option, they are biased towards thinking about why they should choose that option. For example, if you are looking at the chocolate, you are more likely to be thinking about the chocolate and are edging towards choosing the chocolate. In the language of the model, we say you are drifting towards choosing the chocolate while attending to the chocolate. If the chocolate is really much nicer than the apple, you will chose it quickly. In the language of the model, you have a high drift rate. If the chocolate and the apple are pretty evenly matched, you will take ages to decide. In the language of the model, you have a low drift rate.Now, when you look at the chocolate bar, we can't tell whether you are thinking about the sweetness, the high calories, or the pretty wrapper. So we asked people in our lab to choose between options with spatially separate attributes. For example, we had people choose between lotteries where the cash prize and the chance of winning were written separately, next to one another. We were surprised by the result. We found that looking more at a particular lottery was associated with choosing that lottery-just like with the chocolate. But this result did not hold for the separate attributes. You might expect people who looked more at the high cash prize to be more likely to pick the lottery and people who looked more at the low chance of winning to be less likely to pick the lottery. But, across a whole series of experiments, looking at the bad properties of an alternative was just as strongly associated with choosing that alternative as looking at the good properties.Our results show that while the link between what you are looking at and what you are thinking about is solid at the level of whole alternatives, it is broken at the level of the composite attributes. We need to rethink the model of how we choose. In the laboratory, we will replicate our findings across a wide number of tasks. We will test the effect of manipulating which attributes people look at. We will test for a feedback loop where looking increases drift rate, which in turn increases looking, and so on. The outcome will be new experimental evidence and new ideas about how we build up evidence over time to choose.We will translate this laboratory research into the everyday, with real consumers choosing for real. By working with the Financial Conduct Authority, the regulator for consumer financial products, the UK credit card industry, and the Which? consumer group, we will implement field trials, demonstrating these effects in real choices and measuring their impact.