Abstract

For decades, there has been a programme of research to identify the distribution of choice reaction (response) times with the goal of elucidating human decision making. Numerous models have been claimed to fit observations, such as the Gamma, Lognormal, exGaussian, Inverse Gaussian, and Weibull distributions, each with a putative decision-making mechanism. Two contentious but popular models stand out from the crowd: the Drift Diffusion Model (DDM) based on stochastic rise-to-threshold with correct response and error response boundaries, and the linear approach to threshold with ergodic rate (LATER) model based on the claim that saccade reaction times (latency) follow the Reciprocal Normal distribution. 

It is unsettling that so many models are claimed to fit empirical observations. In this presentation, Professor Chris Harris will reveal a discovery that shows that all of the above models are equivalent, and that for decades, studies have been inadvertently fitting the same distribution. The speaker will conclude that the programme of research was ill-posed from the outset, and that it reflects the dubious practice of hypothesis testing.

Short biography

Chris Harris obtained a BSc (Hons) in Physics in 1973, and an MSc in Optics 1974 from Imperial College, London. After working as an optoelectronics engineer, he emigrated to New York where he obtained his PhD in 1986 in the study of human eye movement development. In 1989 he returned to the UK and set up an eye movement laboratory in Great Ormond Street hospital carrying out clinical research into abnormal oculomotor development. 

In 2000, he was appointed Professor of Neuroscience at the Plymouth University where he continues clinical, experimental and theoretical research into visual and motor development in natural and artificial systems. He has published over 100 papers in the field.

https://www.plymouth.ac.uk/staff/christopher-harris