<?xml version="1.0" standalone="yes"?>
<Paper uid="W02-0224">
  <Title>Grounding styles of aged dyads: an exploratory study</Title>
  <Section position="4" start_page="0" end_page="2" type="metho">
    <SectionTitle>
3 Results
</SectionTitle>
    <Paragraph position="0"> Thus, our data comprise both dialogues by older dyads and ones by younger dyads, but these two groups of dialogues were not tightly controlled in their settings and therefore are not appropriate for exact comparison. For the limited purpose of exploratory data analysis, however, it is convenient to tentatively divide our data into these two groups and compare them from various points of view. This section reports four main results of such exploratory comparisons, in terms of (1) the length of disourse units, (2) the types of frequently used acknowledgments, and (3) the frequencies of collaborative completions and echoic responses.</Paragraph>
    <Section position="1" start_page="0" end_page="0" type="sub_section">
      <SectionTitle>
3.1 Utterance units and discourse units
</SectionTitle>
      <Paragraph position="0"> The two groups of dialogues had no significant differences in the total numbers of discourse units (older adults, 446; younger adults, 482) and the total numbers of utterance units (older adults, 1406; younger adults, 1309). This roughly means that older dyads grounded information as frequently as younger dyads, and the numbers of utterances needed for each grounding are about the same in older dyads and in younger dyads.</Paragraph>
      <Paragraph position="1"> Also, the frequencies of occurrences of the seven categories of grounding acts were about the same in older dyads and younger dyads (Figure 1).</Paragraph>
      <Paragraph position="2">  That is, older dyads used grounding acts in about the same variety and variance as younger dyads did.</Paragraph>
    </Section>
    <Section position="2" start_page="0" end_page="2" type="sub_section">
      <SectionTitle>
3.2 Types of Acknowledgements
Initiation-acknowledgements
</SectionTitle>
      <Paragraph position="0"> Generally, an &amp;quot;acknowledgement act&amp;quot; appears at the end of a grounding unit, indicating that conversants have mutually understood what the presenter said. In contrast, an &amp;quot;initiate act&amp;quot; appears at the beginning of a grounding unit, initiating the presentation of a new information unit. Sometimes, a speaker performs both initiation and acknowledgement at the same time, by producing an initiation utterance whose content presupposes the understanding of the preceding presentation.</Paragraph>
      <Paragraph position="1"> An example is found in dialogue excerpt (1) from an older dyad, where one of B's utterances, &amp;quot;a-hon-na-ikatta (that's good),&amp;quot; acknowledges the previous utterance of speaker A while initiating B's presentation of her own information.</Paragraph>
      <Paragraph position="2">  We found that acknowledgements of this type accounts for a 27% of all acknowledgement utterances made by younger adults, while they account for only a 10% of those by older adults (see the top section of each column in Figure 2).</Paragraph>
      <Paragraph position="3"> The difference was significant (t(5)=2.87, .01&lt;p&lt;.05, two-tailed).</Paragraph>
      <Paragraph position="4">  acknowledgements in older dyads and younger dyads General-purpose acknowledgements Beside these dual-functional acknowledgments, there were a significant number of &amp;quot;dedicated&amp;quot; acknowledgements, namely, utterances annotated as &amp;quot;acknowledgements&amp;quot; but not as anything else. Inside these dedicated acknowledgements, however, we can distinguish two types. One type consists of general-purpose acknowledgements, such as &amp;quot;uh-huh&amp;quot; and &amp;quot;m&amp;quot;, that could be used irrespective of the contents of the preceding presentations. The other type comprises special-purpose acknowledgements, such as repeating or paraphrasing responses, whose contents must vary depending on the contents of the preceding presentations. An example of general-purpose acknowledgement is speaker A's short utterance &amp;quot;n (m)&amp;quot; in excerpt (2). In contrast, speaker B's utterance &amp;quot;n-n-mite (m, you saw it)&amp;quot; in excerpt (3) is a case of special-purpose acknowledgment since it paraphrases the preceding utterance by speaker A and thus depends on its specific content.</Paragraph>
      <Paragraph position="5">  acknowledgements into general-purpose and special purpose acknowledgements are subtler than suggested here. For example, an utterance that sounds &amp;quot;n (m)&amp;quot; could be classified as special-purpose if it has a marked prosodic feature that signals the speaker's emotion or feeling.</Paragraph>
      <Paragraph position="6"> Interestingly, older dyads produced more general-purpose acknowledgements (43%) than younger adults did (23%). The difference is highly significant (kh  (2)=67.2, p&lt;.01), as we can also see by comparing the middle sections of the two column in Figure 2.</Paragraph>
      <Paragraph position="7"> Post-grounding acknowledgements Dialogues conducted by older dyads contained several instances of requests for acknowledgement issued after acknowledgements, while those by younger dyads contained no such instances (older dyads, 9; younger dyads, 0). For example, the second request for acknowledgement &amp;quot;ne (see?)&amp;quot; towards the end of excerpt (4) was issued after the acknowledgment &amp;quot;n (m)&amp;quot; by speaker A, requesting further acknowledgement of the presentation &amp;quot;watashi-no-shita-wo (and my younger sister)&amp;quot; that had been already grounded. This phenomenon is particularly interesting since a request for acknowledgement after acknowledgement is not in the scope of Traum's finite-state transition model of grounding sequences.</Paragraph>
    </Section>
    <Section position="3" start_page="2" end_page="2" type="sub_section">
      <SectionTitle>
3.3 Collaborative completion and echoic
</SectionTitle>
      <Paragraph position="0"> response Collaborative completions were slightly more frequent in older dyads than in younger dyads (older adults, 13; younger adults, 7). Likewise, echoic responses were more frequent in older dyads than in younger dyads (older adults, 23; younger adults, 10). Speaker A's second utterance in excerpt (6) is an example of collaborative completion done by an older dyad, and speaker B's second utterance in excerpt (7) is an example of echoic response done by an older speaker.</Paragraph>
    </Section>
  </Section>
  <Section position="5" start_page="2" end_page="2" type="metho">
    <SectionTitle>
4 Discussions
</SectionTitle>
    <Paragraph position="0"> Thus, our exploratory comparison suggests several points of difference between dialogues by older dyads and dialogues by younger dyads. What would these individual differences reveal about common stereotypes about conversations with aged people? Do these individual differences combine themselves to define two different grounding styles attributable to older and younger dyads?</Paragraph>
    <Section position="1" start_page="2" end_page="2" type="sub_section">
      <SectionTitle>
4.1 Initiation-acknowledgement
</SectionTitle>
      <Paragraph position="0"> utterances were less frequent in older dyads.</Paragraph>
      <Paragraph position="1"> Initiation-acknowledgements are dual-functional utterances, performing two grounding acts by single utterance units. Dedicated acknowledgments are mono-functional, performing single grounding functions per single utterance units. Thus, if we define the grounding tempo of a given part of dialogue as the ratio of the number of utterance units to the number of different grounding acts performed by them, then an occurrence of initiation-acknowledgement certainly increases the grounding tempo of the local context.</Paragraph>
      <Paragraph position="2"> In contrast, a dedicated acknowledgement has no such accelerative effect on grounding tempo, and a frequent use of dedicated acknowledgements may even cause impressions of relative slowness of the grounding tempo in the local context. Now our exploratory comparison indicated that older dyads used dedicated acknowledgements more frequently than younger dyads, who used initiation-acknowledgements more frequently. It is then plausible that this contrast in the kinds of frequently used acknowledgements underlies the common impression that conversations with older people are slow-paced and, since the grounding tempo is related to how efficiently information is shared, this contrast might partially account for the common impression that older people understand things slowly.</Paragraph>
    </Section>
    <Section position="2" start_page="2" end_page="2" type="sub_section">
      <SectionTitle>
4.2 Older adutls often acknowledged
</SectionTitle>
      <Paragraph position="0"> after acknowledgements.</Paragraph>
      <Paragraph position="1"> In this regard, an occurrence of post-grounding acknowledgment must have a deceleration effect on the grounding tempo in the local context. For the grounding function it performs, namely, the acknowledgement of the presented information, is one that has been done by the preceding acknowledgement, and thus the ratio of the number of utterance units to the number of grounding functions performed by them is even worse than the case of dedicated acknowledgments. Now again, our exploratory comparison indicated that older dyads used post-grounding acknowledgements more frequently than younger dyads. This contrast therefore might be an added cause to the stereotypes mentioned above, slow-pacedness and slow-understanding.</Paragraph>
      <Paragraph position="2"> 4.3 Older adults tended to use general-purpose acknowledgements more frequently.</Paragraph>
      <Paragraph position="3"> Precisely because the form of a general-purpose acknowledgement, such as &amp;quot;uh-huh&amp;quot; and &amp;quot;m,&amp;quot; does not depend on the content of the utterance being acknowledged, a general-purpose acknowledgement gives only weak evidence of reception or understanding of the content. In contrast, a special-purpose acknowledgement, such as repeating or paraphrasing responses, has stronger evidentiality, since its form is the result of an appropriate choice relative to the content of the acknowledged utterance. Now, our preliminary comparison indicated that older dyads used general-purpose acknowledgements more frequently than younger dyads, and this contrast may well be still another cause to the negative stereotype on older people's capacities for understanding during conversation.</Paragraph>
    </Section>
    <Section position="3" start_page="2" end_page="2" type="sub_section">
      <SectionTitle>
4.4 Two Grounding Styles
</SectionTitle>
      <Paragraph position="0"> Overall, our exploratory comparison suggests a particular style of grounding as characteristic to older dyads. That is, older dyads use more dedicated acknowledgments than dual-functional acknowledgements involving initiations, and among dedicated acknowledgements, older dyads use more general-purpose acknowledgements than special-purpose acknowledgements; they also use post-grounding acknowledgements relatively often, either spontaneously or solicited by requests for acknowledgements. Let us call this grounding style style A, and call the grounding style characterized by the opposite tendencies style B.</Paragraph>
      <Paragraph position="1"> Now we have obtained this hypothetical contrast in grounding styles through an overall comparison of the entire group of older dyads and the entire group of younger dyads. So the question remains how much this contrast applies to individual dyads of older and younger people.</Paragraph>
      <Paragraph position="2"> Aren't there any exceptional older dyads with grounding style B? Any younger dyads with grounding style A? To address these questions, we re-evaluated our data and ranked all ten dialogues in our data according to the ratios of dedicated acknowledgements, the ratios of general-purpose acknowledgements, and the counts of post-grounding acknowledgements (solicited acknowledgements and spontaneous acknowledgements). Table 2 shows the result of ranking, where the hatched cells indicate dialogues by older dyads. Here we see that the contrast of style A and style B divides older dyads and younger dyads fairly clearly. In fact, the separation of older and younger dyads is statistically significant in the ratio of dedicated  =3.75, Z(a)=3.09, p&lt;0.002, two-tailed). Thus, our hypothesis associating style A to older dyads and style B to younger dyads receives some initial supports from this analysis. On the other hand, Table 2 also shows certain exceptions to this association, namely, some older dyads with style B and some younger dyads with style A. This is only natural as we can easily imagine older people who talk like younger people as well as younger people who talk like older people. Styles are styles, and they are not natural traits exclusively possessed by particular species of creatures.</Paragraph>
      <Paragraph position="3"> Table 2. Rank order of ten dialogues according to the ratios of dedicated acknowledgements, the ratios of general-purpose acknowledgements, and the counts of post-grounding acknowledgements (solicited acknowledgements and spontaneous acknowledgements)  percentage rank percentage rank counts rank counts rank 58.41% 1 10.90% 1 0 1 3 1 62.02% 2 18.60% 2 0 1 4 2 80.00% 3 19.40% 3 0 1 5 5.5 81.32% 4 21.50% 4 0 1 5 5.5 84.11% 5 25.20% 5 0 1 5 5.5 84.95% 6 41.30% 6 0 1 5 5.5 88.89% 7 41.80% 7 0 1 6 7 88.99% 8 42.40% 8 1 8 7 8 93.27% 9 48.30% 9 4 9.5 10 9.5 93.33% 10 56.90% 10 4 9.5 10 9.5 *Hatched cells are data of older dyads.</Paragraph>
    </Section>
  </Section>
class="xml-element"></Paper>