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<article xmlns:xlink="http://www.w3.org/1999/xlink">
  <front>
    <journal-meta>
      <journal-title-group>
        <journal-title>Workshop on Supporting Complex Search Tasks, March</journal-title>
      </journal-title-group>
    </journal-meta>
    <article-meta>
      <title-group>
        <article-title>How do Users Perceive Information: Analyzing user feedback while annotating textual units</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>Piyush Arora</string-name>
          <email>parora@computing.dcu.ie</email>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Gareth J. F. Jones</string-name>
          <email>gfjones@computing.dcu.ie</email>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <aff id="aff0">
          <label>0</label>
          <institution>ADAPT Centre, School of Computing, Dublin City University</institution>
          ,
          <country country="IE">Ireland</country>
        </aff>
      </contrib-group>
      <pub-date>
        <year>2017</year>
      </pub-date>
      <volume>11</volume>
      <issue>2017</issue>
      <abstract>
        <p>We describe an initial study of how participants perceive information when they categorize highlighted textual units within a document marked for a given information need. Our investigation explores how users look at different parts of the document and classify textual units within retrieved documents on 4-levels of relevance and importance. We compare how users classify different textual units within a document, and report mean and variance for different users across different topics. Further, we analyze and categorise the reasons provided by users while rating textual units within retrieved documents. This research shows some interesting observations regarding why some parts of the document are regarded as more relevant than others (e.g. it provides contextual information, contains background information) and which kind of information seems to be effective for satisfying the end users (e.g showing examples, providing facts) in a search task. This work is a part of our ongoing investigation into generation of effective surrogates and document summaries based on search topics and user interactions with information.</p>
      </abstract>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>INTRODUCTION</title>
      <p>
        Information retrieval (IR) focuses on optimizing topical relevance
by retrieving documents that are relevant to the user’s
information need [
        <xref ref-type="bibr" rid="ref7">7</xref>
        ]. Initial work in IR focused on assessing documents
relevance at binary levels (relevant and non-relevant items), but
subsequently shifted towards more graded relevance levels (highly
relevant, partially relevant, non relevant items). Work by Spink et
al. [
        <xref ref-type="bibr" rid="ref15">15</xref>
        ] categorizes the prior work on user oriented relevance based
on two mains aspects: 1) levels of relevance, and 2) regions of
relevance. In their work the authors studied different regions of relevance
and their relation to changes in the user’s information problem
definition, the user’s personal knowledge, the searcher’s intermediaries
perception and the user’s criteria for marking relevance judgements.
They examined the criteria for marking retrieved items as relevant,
partially relevant and non-relevant. Further, they proposed methods
by which future search systems should support highly relevant and
partially relevant items depending on the user’s knowledge level, to
assist the user in carrying out complex information seeking activities.
Our work is motivated by this earlier work, but we look at
information within documents at a more fine grained level for a given search
topic.
      </p>
      <p>CHIIR 2017 Workshop on Supporting Complex Search Tasks, Oslo, Norway.
Copyright for the individual papers remains with the authors. Copying permitted for
private and academic purposes. This volume is published and copyrighted by its editors.
Published on CEUR-WS, Volume 1798, http://ceur-ws.org/Vol-1798/.</p>
      <p>
        Recent advances in IR have focused on user centric measures of
utility, satisfaction of information for supporting search tasks and
information seeking [
        <xref ref-type="bibr" rid="ref1 ref11 ref4">1, 4, 11</xref>
        ]. Several studies have examined a move
from document level relevance to within document (sentence and
paragraph) level relevance to extract parts of the documents that can
satisfy a user’s information need [
        <xref ref-type="bibr" rid="ref5 ref9">5, 9</xref>
        ]. Looking for useful, important
and relevant information within a document that can directly provide
information for a user search need can be used for the generation of
effective document surrogates or information cards and to provide
answers to a user’s question [
        <xref ref-type="bibr" rid="ref14 ref2 ref3">2, 3, 14</xref>
        ]. Providing relevant and useful
information is also important to address the information gaps in a
user’s knowledge of a topic and to provide better support for learning
and gaining knowledge [
        <xref ref-type="bibr" rid="ref13 ref16">13, 16</xref>
        ].
      </p>
      <p>
        Hassan et al. defined complex search tasks as a multi-aspect or a
multi-step information need consisting of a set of related tasks [
        <xref ref-type="bibr" rid="ref6">6</xref>
        ]. In
their work, the authors sought to identify and recommend sub-tasks
to users based on their search queries in order to provide support
in the overall search process. Similarly there has been work on
supporting exploratory search and serendipity in web search to address
complex search topics [
        <xref ref-type="bibr" rid="ref12 ref17 ref6 ref8">6, 8, 12, 17</xref>
        ]. Most of this prior work aimed
to support exploratory and investigative activities by grouping user’s
queries and search behavior, and retrieving documents using task or
session level information from the user. Whereas in our work, we try
to study the multi-aspect parts of the information contained within
potential documents to be presented to the user to address a complex
search task. Identifying which information must be shown to users
from a multitude of information from potential relevant documents
originating from different sources is a challenging task. In this
paper, we study how users interpret and perceive information from
within retrieved documents for a given search task. To do this, we
analyze the user’s rating and reasoning while they categorize textual
information within retrieved documents for different search topics
on 4-levels of relevance and importance. We focus on looking within
a document at a granular level of textual (information) units [
        <xref ref-type="bibr" rid="ref9">9</xref>
        ] to
understand why and which parts of the document are more relevant
and important than others. We believe that understanding what kind
of information better supports and satisfies a user’s information need
effectively can help in the overall search process involving multiple
steps.
2
      </p>
    </sec>
    <sec id="sec-2">
      <title>EXPERIMENTAL INVESTIGATION</title>
      <p>In this section, we introduce the design of the user study and dataset
used for our experiments.
2.1</p>
    </sec>
    <sec id="sec-3">
      <title>User Study Design</title>
      <p>Participants were presented with a series of information needs and a
single relevant document for each one. Participants were recruited
through the Prolific crowdsourcing platform1.</p>
      <p>
        TASK: Assessing already highlighted information units (AIHIU):
Participants assessed already highlighted information units on a
scale of [
        <xref ref-type="bibr" rid="ref1 ref2 ref3 ref4">1-4</xref>
        ]. The first author of this paper manually identified
and highlighted topically related textual units from the documents
to be categorized by the users between 4 classes of relevance and
importance:
(1) C1: Highly relevant and important
(2) C2: Fairly relevant and important
(3) C3: Slightly relevant and important
(4) C4: Neither relevant nor important
Participants were asked to explicitly outline the reasons for their
ratings.
      </p>
      <p>
        We merged the dimensions of relevance and importance in a
single scale, as in our related user study 2, users were asked to
find and highlight useful and important parts of the document that
satisfies and addresses the given information need. In the analysis
of the data and user feedback we found that at times users find it
difficult to identify information units which are useful and important,
since it gets quite ambiguous while performing annotations within
document level unless separate topic specific guidelines are provided
as was done by Habernal et al. [
        <xref ref-type="bibr" rid="ref5">5</xref>
        ]. It would be worth exploring
user’s annotation for the above mentioned scale of relevance and
importance separately. But we believe that it will be quite complex
to perform annotations at a granular level within documents for
information at varying scales of relevance, usefulness, importance
separately, unless the definition of these concepts is properly defined
for annotations within the document level. This latter issue is an
important area to be explored in future work, but is beyond the scope
of this paper.
      </p>
      <p>Our study focuses on the following specific research questions:</p>
      <p>RQ-1: How do users rate and perceive information within
retrieved documents for different types of topics?</p>
      <p>RQ-2: How can we categorise user feedback to provide better
support for search topics which are explorative and investigative in
nature?</p>
      <p>Research Contribution: The main contribution of this paper is
the categorization and analysis of user feedback while assessing
textual units within retrieved documents. Our study draws some
important observations and conclusions regarding why some parts
of a document are more relevant than others (e.g. they provide more
contextual information, they contain background information) and
which types of information appear to be effective for satisfying end
users (e.g showing examples, providing facts).
2.2</p>
    </sec>
    <sec id="sec-4">
      <title>Dataset and Study Procedure</title>
      <p>
        We used data from the TREC 2012 session track for our study [
        <xref ref-type="bibr" rid="ref8">8</xref>
        ]. We
selected three information needs from this dataset and at random one
relevant document from the qrels for each of the these information
1https://www.prolific.ac/
2Our study, Titled: Identifying Useful and Important Information within Retrieved
Documents, appears at CHIIR 2017 main conference. This work described in this paper
is an extension and detailed analysis of the main study.
needs. Since this is a comprehensive and cognitively intensive task
for our participants, we opted to concentrate on detailed descriptive
analysis of a small number of documents for this initial study.
      </p>
      <p>
        Differences in the user’s topic familiarity can influence their
search behaviour [
        <xref ref-type="bibr" rid="ref10">10</xref>
        ], thus to ensure participants are familiar with
the topics, we carefully chose the following three simple and generic
topics from the TREC data set
      </p>
      <p>– T0: Wedding Traditions: web document shown to users
majorly contained factual information</p>
      <p>– T1: Smoking Cessation: web document shown to users
majorly contained recommendation related information</p>
      <p>– T2: Junk Food Taxes: web document shown to users majorly
contained opinionated and factual information</p>
      <p>To carry out the user study, topics were organised and always
presented in the same order. Classification of highlighted textual
units with reasons were collected using the Prolific crowdsourcing
platform. Table 1 shows the demographics of the participants. All
participants were native English speakers. In accordance with
standard crowdsourcing practice for this type of work, participants were
paid between 8-9 euros on a per hour basis.
3</p>
    </sec>
    <sec id="sec-5">
      <title>EXPERIMENT AND RESULTS</title>
      <p>
        In this study we asked the annotators to classify already highlighted
textual units on a scale of [
        <xref ref-type="bibr" rid="ref1 ref2 ref3 ref4">1-4</xref>
        ] and provide reasons for their ratings
as discussed in Section 2.1.
3.1
      </p>
    </sec>
    <sec id="sec-6">
      <title>Results and Analysis</title>
      <p>In Table 2, we present the distribution of user’s ratings of highlighted
textual units across different topics and all topics combined. We also
calculate the mean and variance of the user’s ratings to indicate the
spread and diversity in the ratings of a particular user. In Table 3, we
show the generalization of the users’ feedback and reasoning while
categorizing textual units into one of the 4-levels of relevance and
importance. We had a set of 47 textual units in total for all three
documents combined together (T0:14, T1:19 and T2:14) which were
annotated by 7 users, thus the dataset of user’s feedback had 329
statements. A few statements were repetitive in nature and some
were just single word entries such as: clarification, example, tips, etc.
We analyzed the user’s feedback within separate classes of relevance,
where we try to generalize and capture the user feedback effectively
by grouping statements in terms of finding answers to why some
parts of documents are more relevant and important, and which types
of information appears to be effective in satisfying the end users as
shown in Table 3.</p>
      <p>Data analysis indicates that while assessing textual units, user
feedback and reasoning overlaps over closely related levels of
relevance. Most of the information that is marked as highly relevant
and important is considered as self sufficient, users believe that
it provides a complete meaning by itself and contains necessary
sources, references or numbers to backup the statements. Units that
are marked as fairly relevant and important are considered to contain
information related to the topic but are often supplementary in nature
and need context to properly express their meaning. Units that are
marked as slightly relevant and important are often considered to be
related to one or more aspects of the topic. Users found that these
statements lack proper argument and in some cases need supporting
claims and references. Units that are marked as neither relevant nor
important are often considered as incomplete information or having
lack of proper reasoning.
3.2</p>
    </sec>
    <sec id="sec-7">
      <title>Discussion</title>
      <p>Based on the analysis of user’s variations in terms of feedback and
ratings as shown in Table-2 and Table-3, we speculate that when
participants perceive information, it can broadly be categorised into
4 different types:
1) One who contradicts most of the information
2) One who satisfactorily accepts the information
3) One who is more doubtful, and believe that information might
be correct, but wish to get the supporting claims
4) One who finds information to be assumptious (made up), and
believe information is not factual</p>
      <p>We analyzed the user’s specific ratings and feedback across 3
topics as indicated in Table-2. We found that User-1 for topic:
“Wedding traditions”, satisfactorily accepts most of the textual units as
highly relevant and important as the information was more factual in
nature, while for topic: “Smoking Cessation” and “Junk food Taxes”
the user considered the information to be assumptious and thus was
contradicting with the textual units as the documents on these
topics were more opinionated and recommendation based in nature.
User-2 satisfactorily accepts information as highly or fairly relevant
and important across all three topics. User-3 satisfactorily accepts
information as highly relevant and important for topics: “Smoking
cessation” and “Junk food taxes”, but for topic: “Wedding
tradition‘”, slightly misinterpreted the task as discussed below and thus
rated many units as neither relevant nor important. Users (4, 5, 6,
and 7) critically analyzed the information with proper reasons while
generally categorizing units as highly, fairly or slightly relevant and
important.</p>
      <p>Further, analysis of the feedback reveals that sometimes
participants misinterpret the task and develop their own interpretation while
analyzing the information within retrieved document. For example
when they were asked to look at the information regarding Topic
T0: “Wedding traditions that are interesting and different from what
they are used to, and the document that was shown was a factual
one based on the Japanese wedding and tradition two users seemed
to slightly misinterpret the task. We speculate that user-2 wrongly
interpreted the task as categorising textual units based on whether
the information is contemporary or traditional in nature, similarly
user-5 categorised the information while doing comparative analysis
with western wedding traditions and culture.</p>
      <p>This user study opens discussions for future explorations, for
example when and how to provide information to users: in more
detail, in an abstract way, as a gist or summary depending on the
complexity of search tasks and types of document been retrieved
containing opinionated, recommendation or factual information. We
believe the findings of this work will stimulate discussion on: How
can we support users by understanding individual differences and
way of interactions within documents?
4</p>
    </sec>
    <sec id="sec-8">
      <title>CONCLUSIONS AND FUTURE WORK</title>
      <p>The results indicate that annotation varies across users and for same
users across different topics as shown in Table 2. The way users
perceive information varies depending on the source and type of
information such as factual, opinionated, recommendation as
explored in our study. Analyzing users’ reasoning and their feedback
provided some interesting insights on why some parts of the
document are more relevant and important than others and which types
of information better satisfy the end users as discussed in Table 3.</p>
      <p>This is a preliminary investigation and needs further research and
exploration to draw effective conclusion from the studies. This work
opens question for future exploration:</p>
      <p>1) How to group users based on their behaviour patterns in terms of
how they perceive information in documents and support information
accordingly for complex search tasks?</p>
      <p>2) How can we model information support for different types of
topics where type and credibility of information is in question for,
e.g. opinionated, factual, recommendation related, information as
used in this study?</p>
      <p>3) How can results be presented depending on the type of task
in terms of satisfying end users by providing information which is
factual, topically relevant, diverse and novel?</p>
      <p>In future work, we will further explore the topics opened up in this
study with larger numbers of participants. Additionally, the results of
this work will contribute to our broader objective of creation of richer
document surrogates and summaries, and effective presentation of
information to users to promote for effective search and engagement,
and emerging areas such as improving learning through search.
Acknowledgment: We thank the reviewers for their feedback and
comments. This research is supported by Science Foundation Ireland
(SFI) as a part of the ADAPT Centre at Dublin City University (Grant
No: 12/CE/I2267).
27
6
11
3
1.79
1.01</p>
      <sec id="sec-8-1">
        <title>C1 information units</title>
      </sec>
      <sec id="sec-8-2">
        <title>Highly relevant and important</title>
        <sec id="sec-8-2-1">
          <title>Facts</title>
          <p>Examples, tips</p>
          <p>Provide context</p>
          <p>Show attitudes &amp; opinions
Identify commonalities &amp; differences</p>
          <p>Topically relevant
Background information
Indicate benefits, outcomes
Explain &amp; describes process
Provide rationale, motivation</p>
        </sec>
      </sec>
      <sec id="sec-8-3">
        <title>C3 information units</title>
      </sec>
      <sec id="sec-8-4">
        <title>Slightly relevant and important</title>
        <sec id="sec-8-4-1">
          <title>Non specific details</title>
          <p>Background, not topically related
Information meaningless out of context</p>
          <p>Possible solutions</p>
          <p>Comparative analysis
Personalized information</p>
          <p>Context mismatch</p>
          <p>Forecasts &amp; predictions
Partial information on certain aspects
Obvious information</p>
        </sec>
      </sec>
      <sec id="sec-8-5">
        <title>C2 information units</title>
      </sec>
      <sec id="sec-8-6">
        <title>Fairly relevant and important</title>
        <sec id="sec-8-6-1">
          <title>Added details Supportive material, tips, advices Suggestions Opinions</title>
          <p>Quite broad not concrete information
Details about items or aspects missing</p>
          <p>References
Not applicable to all (suggestions)
Evidence or explanation of an aspect
Some aspects (location, time) discussed
Not very detailed information</p>
          <p>Comparisons</p>
          <p>Discusses changes happening
Information indirectly related to tasks</p>
        </sec>
      </sec>
      <sec id="sec-8-7">
        <title>C4 information units</title>
      </sec>
      <sec id="sec-8-8">
        <title>Neither relevant nor important</title>
        <sec id="sec-8-8-1">
          <title>Repetitive information</title>
          <p>Facts and flow missing</p>
          <p>Advices
Mathematical aspects e.g. increment by 25%</p>
          <p>Reasons missing
Contextual information missing</p>
          <p>What and why’s missing
Source of information missing</p>
        </sec>
      </sec>
    </sec>
  </body>
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