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    <journal-meta />
    <article-meta>
      <title-group>
        <article-title>Conversational Crowdsourcing</article-title>
      </title-group>
      <contrib-group>
        <aff id="aff0">
          <label>0</label>
          <institution>Sihang Qiu, Ujwal Gadiraju, Alessandro Bozzon, Geert-Jan Houben Web Information Systems Delft University of Technology</institution>
        </aff>
      </contrib-group>
      <abstract>
        <p>The trend of remote work leads to the prosperity of crowdsourcing marketplaces. In crowdsourcing marketplaces, online workers can select their preferable tasks and then complete them to get paid, while requesters design and publish tasks to acquire their desirable data. The standard user interface of the crowdsourcing task is the web page, where users provide answers using HTML-based web elements, and the task-related information (including instructions and questions) is displayed on a single web page. Although the traditional way of presenting tasks is straightforward, it could negatively affect workers' satisfaction and performance by causing problems such as boredom and fatigue. To address this challenge, we proposed a novel concept - conversational crowdsourcing, which employs conversational interfaces to facilitate crowdsourcing task execution. With conversational crowdsourcing, workers receive task information as messages from a conversational agent, and provide answers by sending messages back to the agent. In this vision paper, we introduce our recent work in terms of using conversational crowdsourcing to improve worker performance and experience by employing novel human-computer interaction affordances. Our findings reveal that conversational crowdsourcing has important implications in improving the worker satisfaction and requester-worker relationship in crowdsourcing marketplaces.</p>
      </abstract>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>1 Introduction</title>
      <p>
        The world is now experiencing an incredible development of artificial intelligence, machine learning,
and robotics. The importance of human input for such novel techniques has been widely acknowledged
for building training datasets, evaluating AI systems, carrying out human-related experiments,
etc [
        <xref ref-type="bibr" rid="ref6 ref9">6, 9</xref>
        ]. Crowdsourcing has become a primary means to effectively collect human from anonymous
users of the Internet, which leads to the prosperity of crowdsourcing marketplaces, such as Amazon’s
Mechanical Turk1, Yandex Toloka2, and Prolific3. The prosperity of crowdsourcing markets has
attracted an increasing number of people to work full-time online. In a crowdsourcing marketplace,
crowd workers can select and complete tasks, offered by requesters who demands the data, to get
paid. Traditionally, crowdsourcing tasks are firstly designed by requesters, and then executed by
crowd workers, both based on the web page. Current crowdsourcing-related studies have taken
great strides in improving the worker performance and output quality [
        <xref ref-type="bibr" rid="ref5">5</xref>
        ], however, the importance
of user experience and satisfaction has been underestimated. Considering the great potential of
crowdsourcing marketplaces, researchers have identified that the future of crowdsourcing will depend
on both organizational performance and worker satisfaction [
        <xref ref-type="bibr" rid="ref16">16</xref>
        ]. However, recent studies have
1https://www.mturk.com/
2https://toloka.yandex.com/
3https://www.prolific.co/
revealed that crowdsourcing in such a monotonous way can lead to problems such as boredom,
fatigue, and high drop-out rates [
        <xref ref-type="bibr" rid="ref10 ref22">10, 22</xref>
        ]. Such problems can negatively affect worker satisfaction and
engagement.
      </p>
      <p>
        Researchers have attempted to design tasks to engage and motivate workers [
        <xref ref-type="bibr" rid="ref19 ref29">19, 29</xref>
        ]. However,
current motivation designs depend on the task type and context. We still look forward to a general
solution that can effectively better engage workers. We have noticed that there has been a rise in
the use of conversational interfaces, which can provide a human-like means of interaction between
the user and virtual assistants, chatbots, or messaging services. We are also witnessing a rapid
proliferation of messaging services such as WhatsApp, Telegram, and Messenger, as smartphones
have been extensively used worldwide. The growing familiarity of people with such messaging
services enables users to master conversational interfaces with a lower barrier. Our previous work [
        <xref ref-type="bibr" rid="ref20">20</xref>
        ]
has explored whether conversational interfaces can be alternatives to standard Web interfaces for
microtask crowdsourcing, by carrying out experiments in a variety of popularly task types. We found
that conversational interfaces could positively affect workers’ satisfaction and an intention for future
use of similar interfaces, and meanwhile achieve comparable worker performance in terms of both
execution time and output accuracy.
      </p>
      <p>However, previous work has only shown that conversational interfaces could be an equivalent
platform to the traditional web interfaces. The advantages of conversational interfaces in microtask
crowdsourcing remain unexplored. Therefore, in this vision paper, we propose a novel concept —
conversational crowdsourcing. To this end, we proposed the workflow of conversational
crowdsourcing and developed a tool to deploy web-based conversational interfaces on popular crowdsourcing
platforms. Based on this, we researched conversational crowdsourcing from two perspectives —
conversation design and novel UI affordances. In terms of conversation design, we specifically
investigated approaches for estimating conversational styles and the effects of conversational styles
on worker performance. As for novel UI affordances, we combined web search with conversational
interfaces to study the effects on human memorability during search sessions. Furthermore, we also
considered gamification elements, and implemented the avatar customization function on
conversational interfaces to understand how avatars could affect worker satisfaction. In the following section,
we will delve into several research questions to fill the knowledge gap.
2</p>
    </sec>
    <sec id="sec-2">
      <title>Research Questions</title>
      <p>Web-based Interface for Conversational Crowdsourcing. Online microtask crowdsourcing enables
the possibility of accomplishing tasks requiring a large number of people. Tasks such as image
annotation, sentiment analysis, and speech transcription can be easily accomplished on the online
crowdsourcing marketplaces. During this process, the crowdsourcing platform is responsible for
worker selection, microtask generation, microtask assignment and answer aggregation, while online
workers interact with a crowdsourcing system to accept and execute a microtask using a worker
interface.</p>
      <p>
        Traditional web-based user interfaces are widely used for the interaction between crowdsourcing
platforms and workers in the majority of prior work, to communicate with workers, transmit
instructions and gather responses thereafter. In our introduced concept of conversational crowdsourcing, a
conversational agent is able to interface online workers with the crowdsourcing platform, facilitating
task execution and task completion [
        <xref ref-type="bibr" rid="ref20 ref23">20, 23</xref>
        ]. To this end, we attempt to address the following research
question:
RQ1: How can the logic and workflow of the conversational crowdsourcing be designed to support
the task execution?
Improving Worker Engagement. Our previous findings have suggested the use of conversational
interfaces as a viable alternative to the existing standard web interfaces. However, little is known
about the impact of conversational microtasking on the engagement of workers. Previous works
have studied the nature of tasks that are popularly crowdsourced on Amazon’s Mechanical Turk,
showing that tasks are often deployed in large batches consisting of similar HITs [
        <xref ref-type="bibr" rid="ref1 ref7">1, 7</xref>
        ]. Long
and monotonous batches of HITs pose challenges with regards to engaging workers, potentially
leading to sloppy work due to boredom and fatigue [
        <xref ref-type="bibr" rid="ref4">4</xref>
        ]. There is a lack of understanding of whether
conversational microtasking would either alleviate or amplify the concerns surrounding worker
engagement. Therefore, we aim to address the following research question.
      </p>
      <p>
        RQ2: To what extent can conversational interfaces improve the worker engagement in microtask
crowdsourcing?
Conversational Style Analysis. The design of the conversation can affect the crowdsourcing outcome.
Previous works in the field of psychology have shown the important role that conversational styles
have on inter-human communication [
        <xref ref-type="bibr" rid="ref17 ref26 ref27">17, 26, 27</xref>
        ]. Having been developed in the context of human
conversations, the insights and conclusions of these works are not directly applicable to conversational
microtasking, since the contrasting goal of workers is to optimally allocate their effort rather than
being immersed in conversations. To the best of our knowledge, the conversational style of neither the
conversational agent (particularly for crowdsourcing) nor the online users (particularly for workers
in the context of microtask crowdsourcing) have been ever studied. Understanding the role of
conversational styles in human computation can help us better adapt strategies to improve output
quality and worker engagement, or better assist and guide workers in the training process. To this
end, there is a need for novel methods for the estimation of conversational styles in the context of
microtask crowdsourcing. Therefore, we will delve into the following research questions:
RQ3: How do conversational agents with different conversational styles affect the performance of
workers and their cognitive load while completing tasks?
RQ4: How can the conversational style of a crowd worker be reliably estimated?
RQ5: To what extent does the conversational style of crowd workers relate to their work outcomes,
perceived engagement, and cognitive task load in different types of tasks?
Enhancing Long-term Memorability. Information finding tasks are rather popular and more
acceptable in online crowdsourcing platforms since it combines with the learning process. Prior studies
in online learning have revealed that conversational systems can significantly improve learning
outcomes [
        <xref ref-type="bibr" rid="ref11 ref18 ref25">11, 18, 25</xref>
        ]. As the goal of learning is to develop a deep understanding of some information,
memorization is an important element [
        <xref ref-type="bibr" rid="ref15 ref2">15, 2</xref>
        ]. Although conversation can produce unique context
linked with information, the effect of conversational systems on human memorability needs further
exploration. We investigated the role of text-based conversational interfaces in online information
finding tasks [
        <xref ref-type="bibr" rid="ref23">23</xref>
        ]. We found that a conversational interface could better engage online users. However,
the question of whether improved user engagement through conversational interfaces leads to better
memorability of information remains unanswered.
      </p>
      <p>To this end, we aim to fill this knowledge gap by proposing novel approaches to improve human
memorability during information search. We specifically focus on information retrieval activities
carried out through the Web search using desktop browsers. Through rigorous experiments, we seek
to address the following research questions.</p>
      <p>
        RQ6: How can human memorability of information consumed in informational web search sessions
be improved?
RQ7: How does the use of conversational interfaces affect the search behavior of users?
Improving Worker Experience. To increase participant engagement and satisfaction, the use of
gamification has received attention in recent crowdsourcing-related works. While most gaming
elements need to be designed based on specific task types, avatar customization is directly applicable
in most contexts. Relevant work in the field of games research has shown that identifying with avatars
can be effective in improving players’ enjoyment and satisfaction [
        <xref ref-type="bibr" rid="ref28 ref3">28, 3</xref>
        ]. The contexts of games and
crowd work are underlined by the need to motivate and engage participants, yet the potential of using
worker avatars to promote identification and improve worker satisfaction in microtask crowdsourcing
has remained unexplored. This is important to investigate, since using worker avatars and assigning
avatars characteristics or personality traits can increase identification [
        <xref ref-type="bibr" rid="ref21 ref28">28, 21</xref>
        ]. Avatar identification
has been studied from three perspectives — similarity identification, embodied identification, and
wishful identification. Prior works have shown that avatar appearance and characteristics can affect
similarity and wishful identification respectively [
        <xref ref-type="bibr" rid="ref12 ref13">12, 13</xref>
        ], whereas embodied identification demands
more avatar operations and interactions, which is very common in video games but not essential in
crowdsourcing. Since the influence of worker avatars in crowd work has remained unexplored, we
know little about their impact on both conventional task interfaces as well as novel conversational
interfaces. We thereby delve into this comparison through our work, to address the following research
questions:
RQ8: How do worker avatars affect worker experience and quality-related outcomes in conventional
web and novel conversational interfaces?
RQ9: How does avatar customization and characterization selection affect worker performance and
satisfaction?
      </p>
    </sec>
    <sec id="sec-3">
      <title>3 Insights</title>
      <p>
        To answer RQ1, we developed a tool for quickly deploying crowdsourcing tasks in a customizable
conversational interface, named TickTalkTurk [
        <xref ref-type="bibr" rid="ref24">24</xref>
        ]. We designed the logic and workflow of the
conversational agent. Our conversational crowdsourcing tasks are mostly performed based on
TickTalkTurk, as shown in Figure 1.
      </p>
      <p>(a) Greetings and Task</p>
      <p>Instructions.</p>
      <p>(b) Interacting with the chatbot
using buttons.</p>
      <p>(c) Interacting with the chatbot
using free text.</p>
      <p>(d) submitting HIT using a
customized HTML component.</p>
      <p>
        To answer RQ2, we conducted online experiments on AMT. We found that conversational interfaces
have positive effects on worker engagement, as well as the perceived cognitive load in comparison to
traditional web interfaces in general. As to RQ3, we found that a suitable conversational style has
the potential to engage workers further (in specific task types), although our results were inconclusive
in this regard. Our work takes crucial strides towards furthering the understanding of conversational
interfaces for microtasking, revealing insights into the role of conversational styles across a variety of
tasks [
        <xref ref-type="bibr" rid="ref23">23</xref>
        ].
      </p>
      <p>To answer RQ4 and RQ5, we conducted experiments to investigate the feasibility of conversational
style estimation for online crowdsourcing. Our results revealed that workers with an Involvement
conversational style have significantly higher output quality, higher user engagement and less cognitive
task load while they are completing a high-difficulty task, and have less task execution time in general.
The findings have important implications on worker performance prediction, task scheduling and
assignment in microtask crowdsourcing.</p>
      <p>To answer RQ6 and RQ7, we conducted an online crowdsourcing experiment in a classical
information retrieval setup. Results revealed that conversational interfaces have the potential to augment
long-term memorability (7.5% lower long-term information loss). Furthermore, we found that users
leveraging conversational interfaces showed a completely different behavior pattern (such
behaviors have been proved to be beneficial for human memorability by previous studies), compared to
traditional web users. Our findings suggest that the conversational interface is a promising tool for
augmenting human memorability, particularly in information finding tasks.</p>
      <p>
        To answer RQ8 and RQ9, we support workers in building their own representations by customizing
the appearance of their avatars. We also ask workers to characterize their avatars before they begin
task execution – by selecting one out of three worker characterizations drawn from related literature
(diligent worker, competent worker, balanced worker) [
        <xref ref-type="bibr" rid="ref14 ref8">14, 8</xref>
        ]. We designed worker avatars and studied
the influence of avatar customization. Experiments have shown that using avatar customization has
significantly impacts on fostering the sense of success in performance and lowering the perceived task
complexity. The analysis of workers’ behaviors and performances shows the existence of similarity
and wishful avatar identification. Our findings have important implications in terms of reducing
perceived workload and improving sense of success in crowdsourcing task design, which is crucial to
the sustainability of the online freelancing marketplace.
      </p>
    </sec>
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