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  <front>
    <journal-meta />
    <article-meta>
      <title-group>
        <article-title>Search User Interface Design for Children: Challenges and Solutions</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>Tatiana Gossen</string-name>
          <email>tatiana.gossen@ovgu.de</email>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Marcus Nitsche</string-name>
          <email>marcus.nitsche@ovgu.de</email>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Andreas Nürnberger</string-name>
          <email>andreas.nuernberger@ovgu.de</email>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <aff id="aff0">
          <label>0</label>
          <institution>Faculty of Computer Science, Otto-von-Guericke-University</institution>
          ,
          <country country="DE">Germany</country>
        </aff>
      </contrib-group>
      <abstract>
        <p>In this paper we describe the main challenges in designing search user interfaces for children. Young users require emotional support, language support, memory and cognitive support, interaction support and support to judge document relevance. We discuss possible solutions for each challenge. We also present a working prototype of a web search interface whose main target group are users of primary school age. Our interface is colourful and voice supported, contains possibilities for both searching through text input and browsing in menu categories, has a guidance avatar for emotional support and a result storage functionality to support children's cognitive recall.</p>
      </abstract>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>INTRODUCTION</title>
      <p>
        In times of digital natives more and more children are going
online. According to a recent report [
        <xref ref-type="bibr" rid="ref8">8</xref>
        ], children of ages five to
nine spend about 28 minutes online daily and this time
continuously grows. The German 2010 KIM1 study [
        <xref ref-type="bibr" rid="ref17">17</xref>
        ] reports that about
60% of the German children of ages six to thirteen use the Internet
and 70% of those use search engines. Children are using the
Internet for different purposes, especially for entertainment like online
1KIM is a German acronym for Children and Media (“Kinder +
Medien, Computer + Internet”). It is a German user study which is
regularly conducted in the form of interviews.
      </p>
      <p>
        Presented at EuroHCIR2012. Copyright c 2012 for the individual papers
by the papers’ authors. Copying permitted only for private and academic
purposes. This volume is published and copyrighted by its editors.
games or watching videos on Youtube, for communication and for
information search, e.g. related to their school activities [
        <xref ref-type="bibr" rid="ref17">17</xref>
        ].
      </p>
      <p>
        In the modern society, finding information in the Internet is an
important skill that a child needs to develop. If a child succeeds
in finding the information, it feels competent and develops
selfconfidence. In contrast, if it is not able to find good results, a child
may develop a feeling of incompetence. That could even lead to a
feeling of inferiority, especially in the “industry versus inferiority”
period of child’s psychosocial development (age 6–12) [
        <xref ref-type="bibr" rid="ref5">5</xref>
        ].
Children’s immaturity in the emotional domain is not the only aspect
that is different from adult users. Children’s cognitive abilities are
also not fully formed [
        <xref ref-type="bibr" rid="ref21">21</xref>
        ]. Thus, children do not have the same
abilities and knowledge as adults and constitute a separate user
group. The special characteristics of children are challenging and
should be considered by the development of web search engines,
including the design of web search user interfaces (UIs).
      </p>
      <p>
        In order to support children in their search, special search
engines for children, have been launched, e.g. kidrex.org, onekey.com,
askkids.com, kidsclick.org, dipty.com, blinde-kuh.de, fragfinn.de,
helles-koepfchen.de, quinturakids.com etc. Currently, their main
purpose is helping children to find only child appropriate content in
the WWW. Another important aspect is the usability of those search
engines. It is of importance that search engines for children match
the particular skills of children in order to increase their usability
for children. Unfortunately, current search engines for children not
always match the skills and abilities of children [
        <xref ref-type="bibr" rid="ref6">6</xref>
        ].
      </p>
      <p>
        The aim of this work is to develop a novel web search UI which
meets the needs of children, i.e. fits their cognitive abilities,
knowledge and provides the necessary emotional support. This interface
should support children in their search in a web document
collection. Our primary focus is textual information retrieval, as web
documents mostly have a textual form and are written in natural
languages. When designing tools for children, there is a need to
target very narrow age groups [
        <xref ref-type="bibr" rid="ref19">19</xref>
        ]. Cognitive abilities and
knowledge of a fourteen years old and a seven years old child strongly
differ. In this paper we concentrate on primary school age children
as in our opinion this user group is the most challenging one. In the
following we underline challenges in the design of web search user
interfaces for young users and present possible design solutions.
2.
      </p>
    </sec>
    <sec id="sec-2">
      <title>DESIGN CHALLENGES &amp; SOLUTIONS</title>
      <p>
        Emotional Support: Based on Erickson’s theory of psychosocial
development [
        <xref ref-type="bibr" rid="ref5">5</xref>
        ] children require emotional support and a feeling of
success. This can be achieved by proper guidance. The idea here is
to provide children with enough help to support their search process
in order to avoid frustration. We propose building a guidance avatar
that captures children’s failures, e.g. getting no results or spelling
mistakes, and explain how to do better.
      </p>
      <p>
        Language Support: Children, especially in the primary school
age, read slowly and are still learning to write [
        <xref ref-type="bibr" rid="ref23">23</xref>
        ]. In addition,
children have a limited domain knowledge [
        <xref ref-type="bibr" rid="ref11">11</xref>
        ] and difficulties with
typing using a keyboard [
        <xref ref-type="bibr" rid="ref22">22</xref>
        ]. This results in problems with query
formulation and spelling errors [
        <xref ref-type="bibr" rid="ref2 ref7">2, 7</xref>
        ]. Therefore, a search UI for
children should provide different possibilities for children to
formulate their information need. We suggest using a browsing menu
with many categories which meet children’s information needs.
This menu should be image based and audio supported in order to
navigate ergonomically and fast within it. Besides the browsing, we
also suggest to provide the opportunity of keyword-oriented search
supported by spelling correction mechanisms. Children can choose
the way they want to start searching. With an increasing domain
knowledge (possibly gained from browsing in categories) children
can employ keyword-oriented search more efficient.
      </p>
      <p>
        Cognitive Support: According to theories of human cognitive
development, human development occurs in a sequential order in
which later knowledge, abilities and skills build upon the previous
ones [
        <xref ref-type="bibr" rid="ref20">20</xref>
        ]. Piaget [
        <xref ref-type="bibr" rid="ref21">21</xref>
        ] describes four development stages. Children
in primary school age are in the concrete operational stage of their
development which is characterized as a stage where children learn
to reason logically and have difficulties with thinking abstractly.
Their understanding is limited to concrete and physical concepts.
Therefore, categories used in the menu should not be abstract and
browsing menu should have a flat hierarchical structure. Metaphors
used in the user interface should be familiar to children and have a
connection to the physical world (this is also advised in [
        <xref ref-type="bibr" rid="ref3">3</xref>
        ]).
      </p>
      <p>
        Memory Support: According to the information processing
theory [
        <xref ref-type="bibr" rid="ref13">13</xref>
        ], information processing of children differs from the adults’
in terms of how they apply information and what memory limits
they have, i.e. children can represent and process less
information than adults. Information retrieval processes may cause
children’s memory to overload. This explains children’s “looping”
behaviour during the information seeking process. Children click,
repeat searches and revisit the same result web page more often
than adults do [
        <xref ref-type="bibr" rid="ref2 ref7">2, 7</xref>
        ]. To support children’s cognitive recall we can
provide a result storage functionality. It is also important to show a
clear back-button or just present the search result in the same
window (e.g. using frames) in order for children not to get lost.
      </p>
      <p>
        Interaction Support: The information processing rate influences
the fine motor skills of children [
        <xref ref-type="bibr" rid="ref10 ref4">4, 10</xref>
        ]. Young children’s
performance in pointing movements, e.g. using a mouse, are lower
than that of adults. Therefore, the search user interface should
prefer simple point-and-click interactions and clickable interface
elements should be large enough to be easily hit [
        <xref ref-type="bibr" rid="ref3">3</xref>
        ].
      </p>
      <p>
        Relevance Support: Children also have difficulties to judge
the relevance of the retrieved documents to their information need
[
        <xref ref-type="bibr" rid="ref12">12</xref>
        ]. Children are frustrated by too many results and do not have
the ability to determine the most relevant and “best” documents
[
        <xref ref-type="bibr" rid="ref14">14</xref>
        ]. A child-suitable form of results presentation can support
children’s judgement of results’ relevance and provide relevance clues.
Each result item should have a website image and its description.
Akkersdijk et al. [
        <xref ref-type="bibr" rid="ref1">1</xref>
        ] also suggest displaying the results using a
Coverflow technique where the user navigates horizontally.
Coverflow allows users to concentrate on one item at a time. It also does
not require complex interactions like scrolling as a vertical results
list used in common search engines.
3.
      </p>
    </sec>
    <sec id="sec-3">
      <title>SEARCH INTERFACE</title>
      <p>
        We considered the requirements for user interface design and
developed a search user interface for children called Knowledge
Journey (KJ). We used multimedia elements in the UI design to make
the appearance attractive for children. We also took into account
that all clickable items are of appropriate size. We used font sizes
larger or equal to 14 pt as advised in [
        <xref ref-type="bibr" rid="ref3">3</xref>
        ].
      </p>
      <p>Our search user interface KJ uses the metaphor of a treasure hunt
where a user takes a journey to gather relevant search results. The
interface of KJ is shown in Fig. 1. It consists of five groups of
elements: a guidance avatar (here a penguin pirate), a treasure chest, a
coverflow, elements for keyword search and a pie-menu for
browsing. In the following we are going to describe each element group.
3.1</p>
    </sec>
    <sec id="sec-4">
      <title>Guidance Avatar</title>
      <p>In order to start a “Knowledge Journey” a child selects a
guidance avatar (see Fig. 2a). The avatar concept is familiar to children
from computer games. It allows individual user personalization,
e.g. girls can select a female pirate or penguin, there are also
figures for younger and older users. The guidance avatar supports
children’s search process in order to avoid frustration: in the
current version it supports children by providing a spelling correction
after a misspelled query is submitted (see Fig. 2b) and enlarges
images of menu categories providing animations (Fig. 1). A further
possible function of the guidance avatar is an explanation how to
search and what to do in case of finding no results.
(a)
(b)</p>
    </sec>
    <sec id="sec-5">
      <title>Browsing Menu</title>
      <p>
        In order to support children who have difficulties to formulate a
query, a browsing menu with many categories is designed. There
exist different types of menus. We used a pie menu as it can be
operated with simple point and click interactions and presents a
good overview of categories. The pie menu is placed on a
steering wheel. We use the metaphor that a steering wheel is used to
define the search coordinates to provide a search direction.
Initially top categories of the menu are shown (see Fig. 3, middle).
We choose menu categories like entertainment, sports and hobbies,
history, universe, geography, nature, persons etc., as they meet the
information needs of children described in [
        <xref ref-type="bibr" rid="ref16">16</xref>
        ]. Each category has
a number of subcategories. Children are comfortable to use a
twolevel hierarchical organized menu for browsing [
        <xref ref-type="bibr" rid="ref11">11</xref>
        ].
Corresponding subcategories are opened when a child clicks on a top category.
      </p>
      <p>
        Mousing over the category triggers an action of a guidance avatar,
i.e. it shows a large animation to explain the category. Icons and
animations are used to indicate categories because images better
match the cognitive skills of children than written words [
        <xref ref-type="bibr" rid="ref9">9</xref>
        ]. They
also make the user interface more attractive for children as they
prefer colourful designs with multimedia content [
        <xref ref-type="bibr" rid="ref15 ref18 ref3">18, 15, 3</xref>
        ]. In
addition, we provide voice support. By placing a mouse long enough
on the pie menu item, a voice explanation is played telling what
category is selected. Users can also hide the menu by clicking in
the middle of it. Then, only the wheel is shown (see Fig. 3, left).
The menu can be opened again by clicking on the wheel. If a child
clicks a category it receives results visualized as a coverflow. The
category name is also placed as a text in the search input field.
3.3
      </p>
    </sec>
    <sec id="sec-6">
      <title>Results Presentation</title>
      <p>The result presentation is shown in Fig. 1. We use a coverflow
where each item is presented on a papyrus roll that contains the
webpage’s title on top, its thumbnail (preview) in the middle, a
textual summary and a result number according to the relevance on
the bottom. A child can interact with our coverflow using simple
point and click operations. It can open a webpage by clicking on
the result item that is in focus or switch to the next or previous page
by clicking on an item that is not in focus. The whole papyrus roll
area is clickable and thus it is easy to hit.</p>
      <p>When designing a search UI for children, search results and links
should not be opened in a new window or tab as this inhibits
backtracking with the browsers’ back button and thus provokes
“looping” behaviour. Users can easily get confused or lost and start
searching for the way back. We decided to open a webpage in the
same window using a frame (see Fig. 4). In order to return to the
search a child clicks on the “X”-Button. It can also store a webpage
using a “+”-Button.
3.4</p>
    </sec>
    <sec id="sec-7">
      <title>Results Storage</title>
      <p>A child can store relevant results in the “treasure chest”. This
form of storage aims to support children’s memory to prevent
cognitive overload. The number of stored results is shown near the
chest. Furthermore, we use physical concepts like the size of the
chest to show the amount of “treasure”, i.e. a chest icon becomes
larger with each additional stored result (compare Fig. 1 and 5).
By clicking on the chest, a journey journal opens (Fig. 5). We use
a book metaphor, where each reversal of the book contains
information about a stored webpage: its thumbnail, a textual summary
and a title. A child can add notes to each website. It can also open
the website again by clicking on its picture in the book. If a child
does not like a website anymore, it can delete it by clicking on the
“-”-Button. Tiles in the form of small website thumbnail (below
the journal) are used to navigate within the book.</p>
    </sec>
    <sec id="sec-8">
      <title>DISCUSSION &amp; OUTLOOK</title>
      <p>In this paper we described the challenges when designing search
user interfaces for children. We demonstrated possible solutions
based on which a novel user interface, called Knowledge Journey,
was designed. We presented the user interface elements of KJ, i.e. a
guidance avatar for emotional support, a treasure chest for memory
support, a pie menu for language support and a coverflow to support
the judgement of results relevancy. The interface also uses simple
interactions to support children’s fine motor skills. A comparative
user study with 28 young users of age seven to twelve (average 9.5
years) was conducted where we compared our user interface with
a Google-like UI. We evaluated what features of both interfaces
children like most or do not like and the results are promising, i.e.
17 participants preferred KJ interface and five liked both. In the
future we are going to do a deep analysis of the study results in
order to improve the interface.</p>
    </sec>
    <sec id="sec-9">
      <title>ACKNOWLEDGEMENTS</title>
      <p>We are grateful to Ina Bosse for her support in development. The
work presented here was partly supported by the German Ministry
of Education and Science (BMBF) within the ViERforES II project,
contract no. 01IM10002B.</p>
    </sec>
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