A Production System for Assigning Beat Strength
What the Rules Should Represent
- Strong beats tend to be equally spaced.
- Strong beats tend not to fall on rests.
- Strong beats tend to occur on every second or third "micropulse".
- The first and last elements of a run tend to be strong.
Issues in Representing the Input
- Is processing left-to-right?
- Are the "micropulses" built into the input?
- Are elements already grouped into runs?
- How is the periodicity represented?
Input and Rules
- Input (initial Working Memory): two kinds of patterns
- The sequence is repeated enough times so that 36 micropulses
appear; each of the positions in the longer sequence is
given a number.
- To represent the sequence, there are two kinds of patterns
- (run ?start ?finish)
- (event ?position)
- Rules do two things
- Create clauses of the form (beat ?position ?strength)
- Modify (beat ?position ?strength) clauses by changing
- An example rule
- Interpretation: Weaken any beat which is on a rest.
- if (beat ?position ?strength)
and (not (event ?position))
then (beat ?position (- ?strength 1))
- Some things we (well, I anyway) will have to worry about
for this particular problem
- The system needs to be able arithmetic on both the left- and right-hand
- The system needs to have a way to update a
clause of the form (beat ?position ?strength) so that the
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Last updated: 16 November 1995
Copyright 1995, The Trustees of