Information Theory and Machine Learning
Research activity report, January-August 2000 - David MacKay
The magnetic recording group at IBM Zurich research labs
are still interacting with us, though
the hoped-for support for one PhD student
did not materialize. IBM have put a code designed by DJCM
into a simulated hard drive and found a 1dB improvement
over their state-of-the-art code. This corresponds to
a 12% increase in stored data density.
DJCM continues work on generalizations of low-density parity-check codes
and on codes robust to synchronization errors.
The collaboration with R.J.McEliece of Caltech
has produced another paper on the theory of
sparse graph codes.
Matthew Davey presented work from his PhD
at the IEEE international symposium on Information Theory, and it
will be published in the leading information theory journal, IEEE-IT.
Simon Wilson defended his thesis successfully in June.
Latent variable models
James Miskin is writing up his thesis on
blind signal separation techniques,
including applications to several data sets:
blurred images; spectral image data from Hitachi; and DNA microarray
data (in collaboration with researchers
from the Department of Obstetrics and
Gynaecology and the Department of Pathology).
David Ward has completed a first round of experiments on
the Dasher interface, which combines an adaptive language model
with a pointer to allow the
user to write text efficiently using two-dimensional continuous
gestures. Alan Blackwell, now a Lecturer in the Computer Laboratory,
has helped us design experiments to quantify the useability
of the interface. After one hour's use, typical users are able to
write, with just one finger, at half their normal ten-finger typing
speed. This work will be presented at a human-computer interaction
conference this November.
David has also been developing improved language models that could
be used both in Dasher and for text compression.
continues to contribute to the assessment and
improvement of departmental teaching.
A survey of students from all four years suggested that
many students pass through a Physics degree without
improvement of their
understanding of basic physical concepts such as Newton's first law.
Through the Royal Institution and the
Gatsby Foundation, Sanjoy also developed and taught a mathematics and physics
enrichment course for high school students in the Cambridge area.
Andrew M. Childs and Ryan B. Patterson,
two visiting undergraduates from Caltech,
have submitted a paper on `Exact sampling from non-attractive distributions using summary
Plans for next year
Ed Ratzer (British) to start a PhD supported by a Mott studentship
and a CASE award from Schlumberger Cambridge Research.
Topic: Error-correcting codes.
Seb Wills (British) to start a PhD supported by an industrial CASE award
from British Telecom. Topic: Inference and learning using simple hardware.
Felix Huerlimann (Swiss) to start a
PhD supported by Microsoft Research Cambridge. Topic: Machine Learning.
John Barry (New Zealand) to start a PhD in January. [Funding details
to be determined.]
David MacKay <email@example.com>
Last modified: Tue Aug 1 15:24:47 2000