ColloquiaJoint Seminar: Jont B. Allen, February 12 at 12:00 noon - BSLC 205

[Margery Ishmael]

Joint Seminar sponsored by the Committee on Computational Neuroscience
& Department of Computer Science

Date: Tuesday, February 12th, 2002
Time:	12:00 noon
Place: BSLC - Room # 205 (924 E. 57th Street)

Speaker: Jont B. Allen, AT&T Shannon Laboratory
Host: Partha Niyogi

Title:	"From Lord Raleigh to Shannon: How do we understand speech?"

Abstract: In 1908 Lord Rayleigh reported on his speech perception studies 
using the "acousticon" (a commercial sound system produced in 1905), 
demonstrating that he was well aware of the importance of the bandwidth in 
speech perception.  It was the development of the telephone that both 
allowed and pushed mathematicians and physicists to develop the science of 
speech perception.  Critical to this development was probability theory.

 From 1910 to 1950 speech perception was extensively studied by telephone 
research departments throughout the world.  However it was the work of 
Harvey Fletcher in 1921 that made the first major breakthrough.  By 1930 
millions of dollars were being spent on speech perception research at the 
newly created Bell Labs.  The key was his quantification of the 
transmission of information, as characterized by the error patterns.  The 
full and final theory was not published until 1959, following Fletcher's 
retirement.  During WWII the Harvard Acoustics Lab took on this 
problem.  The next breakthroughs were provided by George Miller and his 
colleagues.  Miller used concepts from information theory developed at Bell 
Labs by Claude Shannon to quantify speech entropy.  While these studies 
provide key insight into speech perception, they do not take the final 
elusive step that would allow us to build robust automatic speech 
recognition (ASR) machines.

Regardless of what you read in the popular press, ASR is still an 
unresolved problem.  I will attempt to pass along some wisdom I have 
learned over the years on what we now know about human speech recognition 
(HSR).  It is hoped that by learning more about HSR we might make ASR more 
robust to noise and filtering.

My talk will be in three parts. In part one I will describe the 30 years of 
work by Fletcher and his colleagues which resulted in the "articulation 
index", a widely recognized method for characterizing the information 
bearing frequency regions of speech.  In part two I shall describe the work 
of George Miller.  Miller studied the importance of varying the source 
entropy (randomness) in speech perception.  He did this by controlling for 
both the cardiality (size of the test corpus) and the signal to noise ratio 
of the speech samples.  In part three I shall describe my recent 
experimental work in building more robust speech recognition systems.  One 
goal is to make a system that works as well as human listeners in decoding 
degraded (filtered and noisy) nonsense speech sounds.

Bio: Jont B. Allen received a BS in Electrical Engineering from the 
University of Illinois Urbana-Champaign in 1966, and MS and PhD from the 
University of Pennsylvania in 1968 and 1970 respectively.  After graduation 
he joined Bell Laboratories and was in the Acoustics Research Department in 
Murray Hill NJ from 1974 to 1996, as a Distinguished member of technical 
staff.  Since 1996 Dr. Allen is a Technology Leader at AT&T Labs-Research.
http://www.research.att.com/~jba/

Host: Partha Niyogi (773-702-7378)

*Refreshments will be served at 11:45 a.m.*
Persons with a disability who may need assistance should call Don Churilla 
in advance at 773-702-2978