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94 Chapter 7

Table 7.4
Overall classification performance.
Classified
Test Classified Attentional Classified Classified Classified % Correctly
Category Size Approvals Bids Prohibitions Soothings Neutrals Classified
Approval 84 64 15 0 5 0 76.2
Attention 77 21 55 0 0 1 74.3
Prohibition 80 0 1 78 0 1 97.5
Soothing 68 0 0 0 55 13 80.9
Neutral 62 3 4 0 3 52 83.9
All 371 81.9

It is important to note that both classifiers produce acceptable failure modes (i.e., strongly
valenced intents are incorrectly classified as neutrally valenced intents and not as oppositely
valenced ones). All classes are sometimes incorrectly classified as neutral. Approval and
attentional bids are generally classified as one or the other. Approval utterances are occasion-
ally confused for soothing and vice versa. Only one prohibition utterance was incorrectly
classified as an attentional bid, which is acceptable. The single-stage classifier made one
unacceptable error of confusing a neutral utterance as a prohibition. In the multi-stage
classifier, some neutral utterances are classified as approval, attention, and soothing. This
makes sense because the neutral class covers a wide variety of utterances.

7.5 Integration with the Emotion System

The output of the recognizer is integrated into the rest of Kismet’s synthetic nervous system
as shown in figure 7.6. Please refer to chapter 8 for a detailed description of the design
of the emotion system. In this chapter, I briefly present only those aspects of the emotion
system as they are related to integrating recognition of vocal affective intent into Kismet.
In the following discussion, I distinguish human emotions from the computational models
of emotion on Kismet by the following convention: normal font is used when “emotion” is
used as a adjective (such as in emotive responses), boldface font is used when referring to
a computational process (such as the fear process), and quotes are used when making an
analogy to animal or human emotions.
The entry point for the classifier’s result is at the auditory perceptual system. Here, it is
fed into an associated releaser process. In general, there are many different kinds of releasers
defined for Kismet, each combining different contributions from a variety of perceptual and
motivational systems. Here, I only discuss those releasers related to the input from the vocal
classifier. The output of each vocal affect releaser represents its perceptual contribution to