<?xml version="1.0" standalone="yes"?>
<Paper uid="P06-1025">
  <Title>Dependencies between Student State and Speech Recognition Problems in Spoken Tutoring Dialogues</Title>
  <Section position="4" start_page="193" end_page="193" type="intro">
    <SectionTitle>
2 Corpus
</SectionTitle>
    <Paragraph position="0"> The corpus analyzed in this paper consists of 95 experimentally obtained spoken tutoring dialogues between 20 students and our system ITSPOKE (Litman and Forbes-Riley, 2004), a speech-enabled version of the text-based WHY2 conceptual physics tutoring system (VanLehn et al., 2002). When interacting with ITSPOKE, students first type an essay answering a qualitative physics problem using a graphical user interface.</Paragraph>
    <Paragraph position="1"> ITSPOKE then engages the student in spoken dialogue (using speech-based input and output) to correct misconceptions and elicit more complete  We use the term &amp;quot;emotion&amp;quot; loosely to cover both affects and attitudes that can impact student learning.</Paragraph>
    <Paragraph position="2"> explanations, after which the student revises the essay, thereby ending the tutoring or causing another round of tutoring/essay revision. For recognition, we use the Sphinx2 speech recognizer with stochastic language models. Because speech recognition is imperfect, after the data was collected, each student utterance in our corpus was manually transcribed by a project staff member.</Paragraph>
    <Paragraph position="3"> An annotated excerpt from our corpus is shown in Figure 1 (punctuation added for clarity). The excerpts show both what the student said (the STD labels) and what ITSPOKE recognized (the ASR labels). The excerpt is also annotated with concepts that will be described next.</Paragraph>
    <Section position="1" start_page="193" end_page="193" type="sub_section">
      <SectionTitle>
2.1 Speech Recognition Problems (SRP)
</SectionTitle>
      <Paragraph position="0"> One form of SRP is the Rejection. Rejections occur when ITSPOKE is not confident enough in the recognition hypothesis and asks the student to repeat (Figure 1, STD  ). For our kh  analysis, we define the REJ variable with two values: Rej (a rejection occurred in the turn) and noRej (no rejection occurred in the turn). Not surprisingly,  ITSPOKE also misrecognized some student turns. When ITSPOKE heard something different than what the student actually said but was confident in its hypothesis, we call this an ASR Misrecognition (a binary version of the commonly used Word Error Rate) (Figure 1, STD</Paragraph>
    </Section>
  </Section>
class="xml-element"></Paper>