Global Musical Tempo Transformations using Case Based ... - OFAI

All Of Me
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P ID P P
Figure 3.6: First measures of ‘All of me’, with corresponding I/R structures.
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such an analysis for the first measures of the jazz song ‘All of me’. Assuming
that the violation or realization of implications is an essential aspect of the
way humans listen to music, this sequence of structures is would reflect the
listener’s representation of the melody.
Interesting experiments have been carried out by Schellenberg [105, 106]
and Cuddy and Lunney [29], in which they presented subjects with either a
melody [105, 106] or a single melodic interval [29] and asked them to rate
different continuations. These ratings were compared with predictions of
the I/R model (where the effect of the different I/R principles was quantized
by the authors in accordance with the model). It turned out that the
I/R model was able to predict listeners’ ratings well above chance level. A
principal-component analysis of the five I/R principles under consideration
(registral direction, intervallic difference, proximity, closure and registral return)
showed that the model was redundant, in the sense that three of the
principles were highly correlated. Additional experiments were done with
revised versions of the principles. Eventually Schellenberg [106] proposed a
simplified version of the I/R model containing two principles, of which the
first corresponds to revised versions of registral direction/registral return and
the second to proximity. The proximity principle states that listeners prefer
smaller realizing intervals to larger realizing intervals, i.e. small intervals
are more implied than large intervals, regardless of the size of the implicative
interval. The pitch-reversal principle (Schellenberg’s term for the linear
combination of the revised registral direction and registral return principles)
states that listeners prefer the second tone of the realizing interval to be close
to the first tone of the implicative interval. As Schellenberg points out, this
principle extends the proximity principle to tones that are non-contiguous.
Schellenberg found this simplified I/R model to predict listeners responses
better than the original I/R model proposed by Narmour.
3.5.2 Melodic Similarity
In a CBR system where problem descriptions contain melodies, the concept
of melodic similarity will in some form or other have to play a role in the
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