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Information theory meets writing



18:30 - 19:30


The Royal Society, London, 6-9 Carlton House Terrace, London, SW1Y 5AG



Clifford Paterson Lecture 2010 by Professor David MacKay FRS, University of Cambridge

Keyboards are inefficient for two reasons: they do not exploit the predictability of normal language; and they waste the fine analogue capabilities of the user's muscles.  Professor MacKay will present two human-computer interaction systems, both designed from scratch using information theory. A person's gestures are a source of bits, and the sentences they wish to communicate are the sink.  The aim is to maximize the number of bits per second conveyed from user into text. The benefits of this information-theoretic approach are most striking in the case of users with limited physical abilities.

"Dasher" is a communication system that can be driven by one-dimensional or two-dimensional continuous gestures, or by pressing buttons. Users can achieve single-finger writing speeds of 35 words per minute and hands-free writing speeds of 25 words per minute. Dasher works in over one hundred languages and is free software. "Nomon" is a selection system using a single switch.  It adapts to the user's timing accuracy, can be used for any task traditionally solved by 'point and click', and (in contrast to most selection interfaces) can exploit information about the probabilities of the alternatives.

Speaker biography

David MacKay is a Professor at the University of Cambridge and Chief Scientific Advisor to the Department of Energy and Climate Change.  He was awarded the Clifford Paterson Prize Lecture in 2010 for his major contributions to the theories of error correcting codes and neural networks.

Prize information

The Clifford Paterson Lecture is given annually on any aspect of engineering, and a gift of £500 accompanies it. The General Electric Company Limited endowed the lecture in 1975 in honour of Clifford Paterson. Clifford Copland Paterson FRS undertook the creation of the GEC Research Laboratories in 1919. This followed a career at NPL, Teddington where he became a world expert in the measurement of photometric units. He was elected a Fellow of the Royal Society in 1942.

Information theory meets writing The Royal Society, London 6-9 Carlton House Terrace London SW1Y 5AG UK