[uw.lpaig] Solving Dynamic-Input Interpretation Problems.

ylfink@water.waterloo.edu (ylfink) (01/29/88)

DEPARTMENT OF COMPUTER SCIENCE
UNIVERSITY OF WATERLOO
SEMINAR ACTIVITIES

ARTIFICIAL INTELLIGENCE SEMINAR/Recruiting Seminar

                    -  Thursday, February 4, 1988

Ms.   Kathleen  D.  Cebulka,  from  the  University  of
Delaware,   will   speak   on  ``Solving  Dynamic-Input
Interpretation Problems''.

TIME:                3:30 PM

ROOM:              MC 6082

ABSTRACT

Many   problems  in  artificial  intelligence  can   be
viewed   as  interpretation   problems   which have the
common goal of producing a solution that ``explains'' a
given   input.    The  solution  usually takes the form
of  a  set  of beliefs called a hypothesis.  Although a
number  of  researchers have developed  strategies  for
handling  the  static  case  where  the input is fixed,
there  are  many  problems  where the input is received
dynamically  in relatively  small increments.   Usually
the  problem  solver  is  interacting  with  a user who
expects  a  timely  response  after every input, so  it
can   not  postpone   forming a solution while it waits
for  more  complete  information.   As  a  result,  the
problem  solver  must  rely  on  default reasoning  and
hypothesis  revision  techniques since new evidence may
reveal  that  the  current  hypothesis is not the final
answer.

This   talk   describes   a   characterization  of  the
solution  of dynamic-input  interpretation  problems as
a  search  through  a  hypothesis  space.    A   domain
independent   algorithm,  called  the Hypothesize-Test-
Revise   algorithm,   is  presented and contrasted with
an algorithm that produces a hypothesis which  accounts
for  an   entire   sequence  of incremental inputs.  An
advantage  of  the Hypothesize-Test-Revise algorithm is
that it  provides  an efficient strategy for generating
and revising hypotheses in a dynamic environment.