David Frohlich
Hewlett Packard Laboratories
Filton Road,
Stoke Gifford Bristol BS12 6QZ,
UK +44 117 922 8800
dmf@hplb.hpl.hp.com
Owen Daly-Jones
Department of Psychology
University of York
York YO1 5DD, UK
+44 1904 433169
odj1@tower.york.ac.uk
One problem with this strategy is that it ignores the cost of
establishing successful synchronous connections for the
initiator[6] and the disruptive effect they have on the
recipient [4]. In this paper we explore the complimentary
strategy of improving the quality of asynchronous communication
so as to allow initiators to make better use of missed
connection events and to reduce the impact of face-to-face and
telephone interruptions on intended recipients.
Our starting point for the investigation is to see whether many
of the benefits of a shared workspace for telephones carry over
to answerphones or voicemail systems. For example, if we provide
a document background onto which
voicemail partners can write and gesture whilst recording verbal
messages, would they find it useful for discussing complex
graphical information, focusing and organising the talk around
shared artifacts, and generating permanent records of
interaction? More generally, would such voicefax facilities be
viewed as better than voicemail or fax alone?
Despite the extensive literature on multimedia messaging we can
find no clear answers to these questions. In fact the most
relevant work relates to Wang's Freestyle office system which
presented voicefax facilities as a central feature but was never
widely adopted by the target user community [1]. Indirect
evidence for the value of joint verbal and written annotation
comes from two recent studies on collaborative writing, but
these employed independent or static voice annotations in a
document creation task [2,3].
In the rest of the paper we report the findings of a direct
experimental comparison of voicefax with individual voice and
fax facilities for two document-based messaging tasks.
Three independent groups of 10 users performed two tasks on one
of the three systems. All subjects worked in 'manager-secretary'
pairs, with one member of the pair being responsible for
initiating and completing one task. This arrangement introduced
an element of asynchrony into what was otherwise a synchronous
messaging session. The first task was appointment scheduling
using a blank view of one calendar month, while the second task
was equipment booking using a blank booking form. Conflicting
requirements and abilities were built into each situation. Users
were given a maximum of 30 minutes on one of the messaging
systems to finish. They switched on a stopwatch whenever they
became idle waiting for messages.
FIGURE 1. Perceived system value
Analysis of several task outcome measures showed that users of
all three systems reached the same level of task completion with
the same amount of spare 'idle' time (10 out of 30 minutes).
However, this was achieved with half the number of Voicefax than
Fax or Voice messages; a significant reduction from 6 to 3 per
task (H(2)=12.91, p<.05). This means that Voicefax messages
took longer to compose and review but were more effective in
leading to task closure.
One reason for this effect is indicated in Figure 2 which shows
the number of written and spoken words used in each message
type. While significantly fewer words were written in Voicefax
than Fax messages (U=1, p<.001) the same number of words were
spoken as in Voice messages.
FIGURE 2.Mean number of words per message
This led to greater richness, politeness and redundancy in each
message in which users provided more greetings, farewells,
clarifications and explanations than occurred in Fax messages,
but with the same intention of creating a joint written record
of task progress and completion.
Finally we found that users of the Voicefax system made
selective use of the animation of writing and gesture with
speech (see Figure 3). Just over half the Voicefax messages were
composed as 'verbal cover sheets' after the current document had
been annotated, while the rest involved concurrent speech and
writing/gesture. However, even where animation wasn't used it
was most common to keep the document open and in view as context
for the verbal message and to re-use the document in the next
message. Such accompaniment of an evolving document with each
spoken message meant that the verbal discussion was always in
synch' with a shared record of task progress, and contained
multiple references and connections across messages. This is
not true of fax and phone dialogues today.
FIGURE 3.Use of animation
Abstract
We report a pen-based study in which we provided voicefax
facilities for the recording of animated voice, writing and
gesture on a document background. The findings reflect some
cumulative benefits of combining written and spoken media for
asynchronous communication.
Keywords:
multimedia messaging, asynchronous communication,
workspace, annotation, voicemail, fax, pen
Introduction
Many tools for remote collaboration focus on improving the
quality of synchronous communication. For example, in our own
laboratory we have helped to develop a new conferencing product
which enhances telephone calls by adding a shared workspace [5].
METHODS
The basic facilities were provided through the integration of
commercially available hardware and software. We used active
Wacom pen tablet interfaces to a pair of 486 sound- enabled PC's
connected over a Local Area Network. Each machine was running
Lotus ScreenCam and Windows Paintbrush applications and an HP
Labs file transfer programme. Fax-only messaging was supported
by presenting document bit-maps for annotation in Paintbrush and
then transferring the revised Paintbrush file. Voicefax
messaging was supported by allowing users to record a ScreenCam
movie of the fax composition activity with a concurrent verbal
commentary (from any point), and then transferring the
ScreenCam file with the Paintbrush file. Voice-only messaging
was supported by allowing users to make a ScreenCam sound
recording, and transferring this file alone to the other PC.
RESULTS
Subjective reactions to each system were elicited through a
questionnaire following the experimental session. Figure 1 shows
the mean value ratings for each system. All systems were seen to
be equally valuable for both sending and receiving messages but
the Voicefax system was rated significantly more valuable than
the Voice-only system through a trend which placed the Fax-only
system between them (for sending H(2)=8.63, p<.05, for receiving
H(2)=12.70, p<.05). Furthermore, in a direct comparison with
conventional fax, voicemail and face-to-face interaction,
Voicefax users consistently ranked Voicefax second after
face-to-face and before answerphone and fax (W(3)=0.56, p<.05)
As one user put it, Voicefax was "a way of working with
documents with a face-to-face feeling".
CONCLUSION
The benefits of shared workspaces have been shown to carry over
to voicemail in terms of a gain in the clarity, efficiency and
connectedness of messages. Furthermore, animated speech and
writing conveys a 'face-to-face' feeling which might suffice as
an alternative to certain synchronous document-based
interactions at work.
