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  <front>
    <journal-meta>
      <journal-title-group>
        <journal-title>The Effects of Domain
Knowledge on Search Tactic Formulation. JASIST.</journal-title>
      </journal-title-group>
    </journal-meta>
    <article-meta>
      <title-group>
        <article-title>Individual Differences in Exploration and Content Curation Activities within a Cultural Heritage Digital Library</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>Paula Goodale</string-name>
          <email>p.goodale@sheffield.ac.uk</email>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <aff id="aff0">
          <label>0</label>
          <institution>University of Sheffield Sheffield</institution>
          <country country="UK">United Kingdom</country>
        </aff>
      </contrib-group>
      <pub-date>
        <year>2009</year>
      </pub-date>
      <volume>55</volume>
      <issue>3</issue>
      <fpage>9</fpage>
      <lpage>12</lpage>
      <abstract>
        <p>This paper presents empirical results from an evaluation study of a cultural heritage digital library. It focuses on the differences in preferences between novice and expert users for functionality supporting browsing and exploration, when engaged in orientation and content curation tasks. Findings indicate both similarities and differences between novice and expert users. Recommendations for future work are proposed.</p>
      </abstract>
      <kwd-group>
        <kwd>eol&gt;Novice</kwd>
        <kwd>expert</kwd>
        <kwd>information access</kwd>
        <kwd>information seeking</kwd>
        <kwd>exploration</kwd>
        <kwd>content curation</kwd>
        <kwd>cultural heritage</kwd>
        <kwd>digital library</kwd>
      </kwd-group>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>-</title>
      <p>It might therefore be expected that novice users will have a
preference for tools which support browsing and exploration
(discovery) of the digital library content, especially in more
diverse and large-scale collections. As digital collections grow,
individually and in aggregate forms, simple orientation
(understanding ‘what’s here’, i.e. which topics are covered and in
what depth) can be challenging, and might need to be addressed
even before exploration of the content can begin. Additionally,
discovery tools should support the needs of novice users in
finding and selecting content for topic-focused tasks. This need is
likely to be especially acute when an element of creativity and
synthesis is involved, such as content curation.</p>
      <p>In Proceedings of 1st International Workshop on Accessing Cultural
Heritage at Scale (ACHS’16), 22nd June 2016, Newark, NJ, USA.
Copyright 2016 for this paper by its authors. Copying permitted for
private and academic purposes.</p>
      <p>Developers of information seeking support systems that intend to
support users in more exploratory and creative tasks, including
cultural heritage digital libraries, should therefore seek to provide
tools for orientation, finding (non-search), and curating content.
This paper aims to examine these requirements via a
laboratorybased evaluation study of an experimental system (PATHS1) that
offers these types of functionality for a large-scale aggregated
cultural heritage digital library, based upon a UK sub-set of the
Europeana2 content. Specifically, the paper aims to investigate
any potential differences in the preferences of novice and expert
users for these types of tools when engaged in orientation, finding
and content curation tasks.</p>
    </sec>
    <sec id="sec-2">
      <title>2. RELATED WORK</title>
    </sec>
    <sec id="sec-3">
      <title>2.1 Information seeking tasks and systems in digital cultural heritage</title>
      <p>
        Information seeking tasks in the cultural heritage domain are often
more complex and/or exploratory in nature, including
subjectbased searches and less-focused activities, where there is a higher
degree of uncertainty in what is being sought [8][
        <xref ref-type="bibr" rid="ref1">1</xref>
        ]. Exploratory
information seeking activities go beyond simple look-up or
known-item search, incorporating elements of learning (acquiring,
interpreting, comparing, etc.) and investigation (analysis,
evaluation, synthesis, transformation, etc.) [6]. Information
seeking support systems in the area of exploratory search
therefore require a wider range of functionality to support these
more complex activities [7, 15].
      </p>
      <p>The wider range of user interactions in the cultural heritage
domain incorporates content curation and support categories [10].
The second category, curation goes beyond finding into various
elements of information use, including the addition of annotations,
creation of user exhibitions from available content, and
storytelling [10]. These activities are more closely aligned with
information use than with information finding (searching,
browsing and exploration), and represent an opportunity for
cultural heritage digital libraries to provide wider access to
content and to support reuse and creativity.</p>
      <p>Another important element of user requirements in digital cultural
heritage is visual representation of collection items [9]. Support
for serendipity can also prove to be beneficial and popular with
users engaged in less-focused information seeking tasks [12].</p>
    </sec>
    <sec id="sec-4">
      <title>2.2 Novice and expert user differences</title>
      <p>Differences in the needs and behaviors of novice and expert
information seekers has been researched in many domains. In web
1 PATHS Project: http://www.paths-proejct.eu
2 Europeana: http://www.europeana.eu/portal/
search, domain expertise results in different search strategies and
more successful results in finding relevant content [13]. Domain
knowledge also results in more focused, systematic search tactics
within digital libraries [14]. However, whilst domain knowledge
enhances search success, technical skills may offset this to some
degree, thereby indicating that those lacking in both domain
knowledge and web search expertise are doubly disadvantaged
[4].</p>
      <p>
        In the cultural heritage domain, more experienced users are likely
to be scholars and researchers in humanities subject areas, as well
as cultural heritage professionals, whilst less experienced users
may be from educational and general interest categories [3, 11].
Expert users in cultural heritage undertake a wide variety of tasks
including known-item search and more exploratory activities [
        <xref ref-type="bibr" rid="ref1">1</xref>
        ].
Moreover, novice users involved in leisure activities also
undertake a variety of information seeking tasks, and are highly
visually focused, as well as engaging in elements of
meaningmaking [9].
      </p>
    </sec>
    <sec id="sec-5">
      <title>3. METHODS</title>
      <p>The results presented in this paper are derived from a
comprehensive evaluation study of a prototype of an information
seeking support system designed to investigate functionality for
the support of exploration and curation of content in large-scale
cultural heritage digital libraries, created during the PATHS
project. The study was carried out under controlled conditions in a
laboratory setting, utilizing a variety of simulated work tasks [2]
as a means of gaining feedback on system usability and
usefulness, to inform future system design, and to investigate user
preferences, behaviors, and interactions in this relatively novel
context. Screenshots of the system are shown in figures 1-3
below, illustrating thesaurus, map and path functionality, offered
as different means of exploring the content in the collection and of
curating content. The prototype PATHS system contained c.1
million items selected from UK institutions in the Europeana
digital library,</p>
    </sec>
    <sec id="sec-6">
      <title>3.1 Tasks</title>
      <p>During the evaluation session users were invited to complete five
short orientation and information seeking tasks lasting 5 minutes
each, followed by one 30-minute content curation task. This paper
focuses on the results of one of the orientation tasks and the
content curation task.</p>
      <p>The orientation task required users to investigate the topics
available in the collection, using any of three tools designed to
support browsing and exploration (thesaurus, tag cloud and map).
Feedback was then supplied on the ease of use and usefulness of
each tool using 5-point semantic differential scales, and the user’s
rank order of preference for the three tools (1st, 2nd, 3rd).
The content curation task entailed finding and selecting content
(items held within the digital library) on a topic of the user’s own
choice, then organizing and annotating these items to form a
meaningful route (path) through the collection. This task therefore
required the user to employ tactics to find content via the search
box and/or the exploration tools used in the earlier orientation
task, as well as the more creative element of the activity. The
whole task can be considered as exploratory [5] as it is relatively
non-prescriptive and open-ended, and incorporates elements of
discovery and synthesis [6].</p>
    </sec>
    <sec id="sec-7">
      <title>3.2 Sample</title>
      <p>Sample size was 34 participants, comprising 24 novice users and
10 expert users. Novice users were categorized as those with a
more general knowledge of cultural heritage (low subject/domain
knowledge), and expert users as those with a higher degree of
subject knowledge gained from accessing cultural heritage
collections for work-related use. A majority of users (n=32)
selfreported either an intermediate or high level of experience in
using web search, which it has been suggested may offset a lack
of subject and domain knowledge to some degree [4].</p>
    </sec>
    <sec id="sec-8">
      <title>4. RESULTS</title>
      <p>Data from user feedback on the two tasks was analysed for user
differences according to the novice and expert categorization.</p>
    </sec>
    <sec id="sec-9">
      <title>4.1 Orientation</title>
      <p>Both novice (66.7%) and expert (70%) user types were emphatic
in their placement of the thesaurus as the most useful for aiding
orientation, i.e. finding out ‘what’s here’ (Table 1). There was
more of a split for the tag cloud and the map, with a majority of
novice users placing each of these in 3rd place, whilst expert users
placed these more emphatically in 2nd and 3rd paces respectively.
A majority of both user types placed the relatively novel ‘map’
tool in third place, although more of each type also placed it in
first position than they did the tag cloud. This difference may be
accounted for by the relative novelty of the map, but other factors
may also be at play, such as a preference for image vs text
visualizations.</p>
      <sec id="sec-9-1">
        <title>Thesaurus</title>
      </sec>
      <sec id="sec-9-2">
        <title>Tag cloud Map Novice Expert</title>
        <p>Similarly, 79% of novice users and 80% of expert users rated the
thesaurus as either very useful or useful, and 75% and 90%
respectively rated it as very easy or easy to use, on 5-point
semantic differential scales. However, a difference of opinion was
found on the tag cloud, with novice users rating it as less useful
(33%) and easy to use (50%), than expert users (80% each useful
and easy to use). In contrast, novices were somewhat more
favorable towards the map tool, 46% useful and easy to use, than
expert users, 40% useful and easy to use.</p>
        <p>It seems therefore that the thesaurus is the overall winner for both
user types, but that novice users found the map more useful than
the tag cloud, and vice versa for expert users.</p>
      </sec>
    </sec>
    <sec id="sec-10">
      <title>4.2 Finding content</title>
      <p>Feedback on the usefulness of tools in finding content of interest
for the content curation task was given on a wider range of
functionality, including the search box, the thesaurus, tag cloud
and map tools, browsing of search results and filtering using
facets, recommendations in the form of selected (featured) and
related items, metadata, and links to background information in
Wikipedia. Again a 5-point differential scale was used (very
useful to useless), with an additional category for ‘did not use’.
As might be expected, all users used the search box, although
expert users were more emphatic in it being very useful (80%)
than novice users (66.7%). As in the orientation task, the
thesaurus was deemed the most useful exploration tool, with 46%
of novices finding it very useful or useful, compared with 20% of
expert users.</p>
      <p>Expert users were more likely to rate the usefulness of metadata
driven tools, including facets (40%) and metadata keyword links
(80%) than novice users (25% and 42% respectively).
Interestingly, experts were also more likely to find useful the
recommendations in the form of related and selected items, and
browsing of search results pages, than novice users. This
unexpected finding for search results pages may arise from more
successful searches by expert users, or simply that they had a
better idea of what they were looking for and would ‘know it
when I see it’.</p>
      <p>Overall then, it seems that novices rate the thesaurus most highly
of all the exploratory tools offered, and that experts are more
likely to find a wider range of tools useful, including those such as
facets and subject metadata that might require more specialist
knowledge to interpret.</p>
    </sec>
    <sec id="sec-11">
      <title>4.3 Curating content</title>
      <p>The first stage of curating content is to select items for inclusion.
Whilst directly related to finding content, there is a more active
level of intellectual effort, with choices being made amongst
available content, and potentially disregarding some items in
favor of others. Users gave feedback on both the information used
to make these decisions and the criteria by which items were
selected.</p>
      <p>As expected, all users, novice and expert, favored images as a
primary element of their decision-making process (Table 2). This
is unsurprising since it is widely accepted that using cultural
heritage collections is a highly visual process, and the curatorial
task may be even more visual in nature. It is also clear that
novices used much less ‘other’ non-visual information than expert
users in making their selections. This difference is most marked in
relation to metadata, used by 60% of expert users, but only 12.5%
of novice users.</p>
      <sec id="sec-11-1">
        <title>Novice</title>
      </sec>
      <sec id="sec-11-2">
        <title>Expert</title>
      </sec>
      <sec id="sec-11-3">
        <title>Information used Criteria used</title>
        <p>image
title
description
metadata
typical
unusual/unique
aesthetics
interesting
95.8%
66.7%
50.0%
12.5%
75.0%
4.2%
62.5%
29.2%
100.0%
80.0%
70.0%
60.0%
40.0%
10.0%
60.0%
30.0%
available 33.3% 30.0%
Table 2: Information and criteria used for selecting content,
novice/expert users
Criteria used for inclusion of specific items had commonalities
and differences (Table 2). Novices and experts were relatively
similar in their choice of aesthetically pleasing items (62.5% and
60% respectively), reinforcing the finding on the importance of
images. Both user types were similar in their selection based upon
interesting descriptions and choosing the only items available on
their chosen topic. However, novices (75%) were much more
likely to choose typical examples than expert users (40%).
At the next stage of content curation, the items must be arranged
in some order and might also be augmented with annotations to
add context and aid understanding by the eventual user. There is a
striking difference between novice and expert users in ordering
their content. Expert users arranged content by theme (40%) and
narrative (50%). A majority of novice users also preferred a
thematic arrangement (54%), but smaller proportions used criteria
such as chronology, geography, narrative, geography, importance,
and no particular order. This may indicate that experts have a
more specific idea about the nature of curation, incorporating
themes and narratives, but it is also clear that less-experienced
users are also drawn towards thematic arrangements.</p>
        <p>Finally, novice users were less critical of the curated content they
produced during this task. Rating the quality of their output on a
scale of 1-10, 21% of novices selected a score of 6 or above,
compared to none of the expert users. In contrast, 60% of experts
rated their output in the range 1-3, compared with 50% of novices.
Additionally, the highest rating given by expert users was 5 out of
10, compared to 9 out of 10 for novice users. It seems that expert
users had a clearer idea of what their curated content should look
like, both in terms of arrangement and quality of content. In free
text feedback, many users commented that they would like better
quality images and time to add more contextual annotations to
their curated content.</p>
      </sec>
    </sec>
    <sec id="sec-12">
      <title>5. DISCUSSION</title>
      <p>During this study, we have investigated the differences between
novice and expert users in their preferences and choices for tools
to support more exploratory information seeking and in
information use in the form of content curation, within the context
of a large-scale aggregated cultural heritage digital library. Whilst
search was still the primary choice for all users, novices were
more likely to use exploratory tools to augment their orientation
and finding activities. Specifically, novices were found to be more
pre-disposed to using a thesaurus tool for exploration of the
content than expert users, and were also more open to using other
exploratory tools. In contrast, experts were more likely to make
use of more specialist tools based upon collection metadata, such
as facets and subject keywords.</p>
      <p>Given the challenges experienced by novices from lower levels of
subject and domain knowledge, it is likely that these results may
be at least partially explained by the support provided by the
exploration tools in overcoming this lower level of knowledge.
The thesaurus in particular lays open the main topics within the
collection, and is easy to navigate, comprising hierarchical
categories and sub-categories. A further bonus may be that the
thesaurus was derived from Wikipedia subject headings [ref
anon], giving a more informal level of access to subject-related
content.</p>
      <p>However, differences by novice and expert categorization may not
be the only factors affecting accessibility of cultural heritage
content. Previous analyses of this evaluation study have also
identified differences in behavior and preferences according to
cognitive style [ref anon], selected demographics [ref anon] and
variations in the system functionality from simple to more
complex [ref anon]. It is therefore even more pertinent to consider
designing for a diverse range of users to ensure the greatest
potential for increasing access, although perhaps focusing on
those tools that aid the widest range of users, in this case the
thesaurus which was well-received by novices and experts alike.</p>
    </sec>
    <sec id="sec-13">
      <title>6. CONCLUSIONS</title>
      <p>User differences can impact upon successful assess to content
within large-scale cultural heritage digital libraries. Out of all of
these criteria though, it is likely that the novice / expert
differences are most likely to affect overall success in finding and
exploring content. Novice and expert users express somewhat
different preferences for tools to support exploration of digital
cultural heritage collections. They also make some different and
some similar choices when engaged in finding and creating
material for content curation activities. As information seeking
support systems for collections are increasingly targeted at a more
diverse range of users from novice to expert in their range of
subject and domain knowledge, it is therefore necessary to
understand and accommodate these user requirements and
differences through functionality that supports a range of
preferences and abilities.</p>
      <p>In future work we will also undertake more detailed analysis of
actual user behavior from screen recordings and transaction logs.
This will provide a useful contrast in what users report as
preferences and choices, against what functionality they use in
practice, as well as uncovering sequences and patterns of
behavior, providing a basis for recommendations for system
design for the support of exploration in cultural heritage
collections. Further, more naturalistic studies of users interacting
with systems that are in the public domain, undertaking their own
tasks under less controlled conditions will also be of interest, to
provide insights into the levels of take-up and actual usage of
these types of information seeking support tools in cultural
heritage collections ‘in the wild’.</p>
    </sec>
    <sec id="sec-14">
      <title>7. ACKNOWLEDGMENTS</title>
      <p>The research leading to these results has received funding from
the European Community’s Seventh Framework Programme
(FP7/2007-2013) under grant agreement no. 270082. The author
acknowledges the contribution of all project partners involved in
PATHS (see: http://www.paths-project.eu).</p>
      <p>Wilson, M.L. et al. 2010. From Keyword Search to
Exploration: Designing Future Search Interfaces for the
Web. Foundations and Trends in Web Science. 2, 1, 1–
97.</p>
    </sec>
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