1. Emer Gilmartin, Carl Vogel, ADAPT Centre Trinity College Dublin
Stitching together the conversation – design considerations for casual talk 
Emer Gilmartin, Carl Vogel,
ADAPT Centre
Trinity College Dublin

2. Hello Santa Fe
I’m really sorry not to be here in person, and hope all are enjoying workshop!

3. Motivation
To better understand the bundle of signals in conversation

4. SDS technology based on
The Problem: Building companion dialogue systems entails understanding of casual dialogue but…
Much linguistic theory is based on language similar to writing but highly unlike talk
regards spoken interaction as debased, chaotic
SDS technology based on
Practical Dialogue Hypothesis (Allen, 2000)
Constraint introduced to make dialogue modelling tractable
Much corpus study of spoken interaction based on Task-based Dialogue
Information gap activities – MapTask (HCRC), DiaPix (Lucid)
Meetings – AMI, ICSI
These are not corpora of casual or social talk
The background motivation for this work is to design more human like dialog systems.

5. Transactional v Interactional Conversation
Ordering a pizza (transactional)
performing a well-defined task
content (‘What?’) vital for success
Chat with neighbour (interactional)
building/maintaining social bonds
social (‘How?’) very important
Longer form (c 1 hr) casual conversation
‘continuing state of incipient talk’
Interested in the structure of such conversations

6. Casual Conversation
‘Unmarked’ central case of spoken interaction
A lot of theory and transcript based work, need for multimodal corpus based studies
Not monolithic. Can be described at level above the utterance or adjacency paiar
as a series of phases: greeting, approach, centre, leavetaking (Ventola)
as highly interactive ‘chat’ and more monologic ‘chunk’ phases
Often multiparty, variable duration – up to several hours
Most existing corpora task-based, existing casual talk corpora dyadic and short duration (5-15 minutes)

7. Chat and Chunk
BOTH FRAMES SHOW 2 MINUTES OF 5-PARTY CONVERSATION – 1 LINE PER PERSON
DARK GREEN IS SPEECH, GREY IS SILENCE, YELLOW IS LAUGHTER
THE TOP FRAME SHOWS INTERACTIVE CHAT
BOTTOM FRAME SHOWS MORE CHUNK-LIKE TALK WITH LONG TURNS BY INDIVIDUAL SPEAKERS – FOR EXAMPLE SPEAKER 3 HAS A CHUNK FOR MOST OF THE MIDDLE OF THIS FRAME

8. Data – 6 multiparty conversation of around 1 hour each
IWSDS 2016
a segment where one speaker takes the floor and is allowed to dominate the conversation for an extended period.
The annotations resulted in 213 chat segments and 358 chunk segments

9. Annotated into chat and chunk
All conversations manually segmented at Intonational Phrase (IP) level
Manual segmentation was necessary as number of speakers made automatic speaker diarization impossible
All conversations transcribed
Chunks marked using Slade and Eggins’ definition of chunks –`a segment where one speaker takes the floor and is allowed to dominate the conversation for an extended period.’
All non-chunk conversation considered chat.
Guidelines for annotation created to help disambiguate unclear cases.

10. Chat/Chunk Analysis Analysis of Chat and Chunk Phases January 15, 2016
IWSDS 2016
Analysis of Chat and Chunk Phases
Phase length, laughter, overlap contrasted in chat and chunk phases. Generally more chat at conversation beginnings, more time overall spent in chunk phases and more chunk phases in all conversations. Probability of transition from chunk to chat falls as conversation progresses.
Phase Duration
Mean chunk duration approx. 34s
Mean chat duration approx. 28s
Chunk duration distribution tighter
Distributions significantly different
Chunk duration
Not speaker , gender, conversation dependent

11. Laughter More laughter in chat than chunk Median laughter proportions:
Chat – 5.4% of production
Chunk – 2.2% of production
81% of laughter in chunks non-owners

12. Chat/Chunk analysis Overlapping Speech More overlap in chat than chunk
Median overlap proportions
Chunks % (mean = 7.3%)
Chat % (mean = 16%)
Floor Occupancy (% time spent)
Overlap and silence more common in chat than in chunk phases
More than two speakers in overlap rare

13. Work in Progress: Topic
Topic is a feature used to segment text (written or oral)
Topic segmentation for casual talk is difficult – shading and shifting
Chat/Chunk is distinguishable from speech and silence annotation
Could chat/chunk phases correspond to topic boundaries in dialogue?
Dataset has been annotated for topic, using ‘aboutness’
Currently working on comparing and contrasting chat/chunk and topic segments in terms of temporal span

14. Questions? gilmare@tcd.ie
Thank You
Questions?