=Paper= {{Paper |id=None |storemode=property |title=Constructing Narrative Visualizations as a Means of Increasing Learner Engagement |pdfUrl=https://ceur-ws.org/Vol-1210/datawiz2014_13.pdf |volume=Vol-1210 |dblpUrl=https://dblp.org/rec/conf/ht/YousufC14 }} ==Constructing Narrative Visualizations as a Means of Increasing Learner Engagement== https://ceur-ws.org/Vol-1210/datawiz2014_13.pdf
        Constructing Narrative Visualizations as a means of
                 Increasing Learner Engagement
                           Bilal Yousuf                                                       Owen Conlan
                  KDEG, Trinity College Dublin                                        KDEG, Trinity College Dublin
                       Dublin, Ireland                                                     Dublin, Ireland
                    yousufbi@scss.tcd.ie                                               Owen.Conlan@scss.tcd.ie



ABSTRACT                                                                research addressed in this paper presents a framework, VisEN
Increasingly visualization systems are using storytelling to present    (Visual Exploration with Narrative), which aims to provide a
complex data. However, many approaches neglect enabling users           novel way to extract knowledge and meaning from data. VisEN
to independently explore details within the story. The research         supports users in the role of narrative composers to analyze
presented in this paper provides an overview of the                     potentially complex data through advanced web based interfaces
implementation and discusses the evaluation of a novel                  to construct narratives. The narratives include explorations paths
framework (VisEN), which aims to allow users to construct               to facilitate data drill downs and viewing related data. The
narratives containing multiple exploration paths. The narratives        narratives are automatically transformed into personalized visual
are told through dynamically generated visualization techniques,        narratives for end users, who can analyze and explore sections of
which are personalized for individual end users, and where every        the narrative through multiple interactive visualization techniques
visualization technique in the narrative can be further explored.       and gain a deep understanding of the data.
The evaluation described assesses the role personalized visual          This paper discusses the implementation overview, evaluation and
narratives had in increasing engagement of weaker students with         preliminary results of two key components of the VisEN
an online database SQL course. It was found that weaker students        framework: the Narrative Builder and the Visual Narrative
who regularly interacted with their personalized visual narratives      Explorer. The aim of the Narrative Builder is to enable narrative
showed an improvement in engagement.                                    composers to construct explorable narratives through an advanced
                                                                        web–based interface, which enables the analysis of potentially
Categories and Subject Descriptors                                      complex data without dealing with data complexity issues. The
H.3.5 [Online Information Services]: Web-based services; H.5.2          aim of the Visual Narrative Explorer is to personalize the visual
[User Interface] Graphical User Interface; H.5.4 [Hypertext/            narratives for end users and facilitate analysis and exploration of
Hypermedia]: Architectures                                              these narratives. VisEN was deployed to the AMAS [20]
                                                                        Personalized Learning Environment (PLE), to provide
                                                                        personalized visual narratives to 108 students who participated in
General Terms                                                           an online SQL course. Two evaluations were completed with the
Design, Experimentation, Human Factors, Performance                     first analyzing how effective the AMAS course professor found
                                                                        the user interfaces provided by the Narrative Builder to build
Keywords                                                                explorable visual narratives. The second evaluation focused on
Visualizations, Personalized Visual Narratives, Visual Interaction      weaker students’ level of engagement (“participation in
and Exploration                                                         educationally effective practices” [17]). In particular, it analyzed
                                                                        how effective the personalized visual narratives were in allowing
                                                                        weaker students to extract meaning from their activity data, in
1. INTRODUCTION                                                         order to motivate them to engage with the course. The results of
Research in the field on Information Visualization has largely          both evaluations were very encouraging and it was found that
been focused on visual analytics and exploration, whereas               these learners were drawn to their visual narratives in order to
research in visual presentation and storytelling has recently started   understand and improve their engagement with the course.
to gain momentum. Storytelling in information visualization, or
narrative as it is referred to in this work, can be defined as an       The remainder of this paper is structured as follows: Section 2
ordered sequence of steps consisting of visualizations, which are       discusses the VisEN framework approach. Section 3 presents a
linked or connected to make the communicated message more               review of the related work. Section 4 describes an implementation
memorable [1]. Stories provide effective ways of highlighting           overview of VisEN. Section 5 presents two use cases; the first
facts, making points and passing on information [16], while             describing a domain expert using VisEN to construct visual
visualizations facilitate a simple means to understand digitized        narratives, and the second describing a learner using her
data as they map data attributes to visual properties [6]. The          personalized visual narratives to gain a thorough understanding of
                                                                        her personal course log data. Section 6 evaluates effectiveness of
                                                                        VisEN when deployed to a PLE and discusses preliminary results.
                                                                        Finally, section 7 discusses conclusions and future work.

                                                                        2. VISEN APPROACH
                                                                        VisEN automatically transforms narratives into explorable visual
                                                                        narratives. This transformation requires data characterization and
mappings to transform data to appropriate visualization                 selected data through a further visualization. However, with drill
techniques. Data characterization or data transformation [6]            downs, users reach an end point where their exploration must.
involves analyzing data to facilitate automated mappings to             Exploration paths provided by VisEN are linked to elements in
visualization techniques. To enable this mapping or visual              the visual narrative and when these elements are clicked,
encoding [6], the affordances and characteristics of visualization      visualization techniques are generated rendering a drill down view
techniques are required, for example, through a matrix. VisEN           or a related data view of the element selected. Drill down views
narratives consist of data slices, which are constructed using data     show the details surrounding a selected element, whereas related
fields, metadata, filters and aggregations. Data slices form the        data views show data which shares relationships with the selected
chapters or sections of the narrative.                                  element. When a user reaches the lowest point in a drill down, she
                                                                        always has the option to view related data. Visualizations have
When a data slice is constructed, visualizations that can render the
                                                                        been used in Technology Enhanced Learning (TEL) to present
data are automatically generated and presented to the narrative
                                                                        student activity data and peer comparisons [11, 22] to motivate
composer as a set. The narrative composer decides which
                                                                        students. However, these are not represented through visual
visualizations to keep in the set. This action introduces humans
                                                                        narratives, where users can explore the data presented.
into the visual matching process. This results in a refined set of
visualizations for a data slice, and takes place before the narrative   Personalized visual narratives can aid the process of
is transformed into a visual narrative. VisEN automatically             understanding complex data as they can present personalized data
generates personalized exploration paths to allow end users to          and provide visualizations that suit individual preferences. In
select elements within visualizations and view details or view          Tableau Story, Tableau [26] selects the most suitable visualization
related data through other visualizations. The exploration paths        for the story point and this can be changed by the analyst.
are generated based on users preferences and consists of                Similarly Google Fusion Tables [10] uses a suitable visualization
visualizations showing details and related data to the narrative        for the data. However, we find on many occasions, a number of
viewed.                                                                 visualization techniques are suitable to render the same data. The
                                                                        visualizations generated by these systems are not personalized to
To complete the narrative, the narrative composer connects the
                                                                        end user preferences. In TEL, a number of systems [2, 3, 21]
data slices to each other in a chronological order and publishes it.
                                                                        provide personalized visualization forming part of the learning
Figure 1 shows a simplified view of the process used by VisEN to
                                                                        module. VisEN’s architecture consists of a Personalization
produce personalized explorable visual narratives.
                                                                        Engine, which generates personalized exploration paths for end
                                                                        users. User data preferences are stored in a user model, which are
                                                                        used to personalize the exploration paths.
                                                                        From the visualization tools that support visual interactions and
                                                                        explorations, Spotfire [27] supports drill down explorations,
                                                                        however, the exploration path is fixed and an end user has the
                                                                        option to either view the details behind a data point or not. The
                                                                        exploration is not independent of the path constructed by the
                                                                        analyst. VisEN provides multiple exploration paths from each
                      Figure 1: VisEN Flow                              data slice, allowing end users to explore various tailored paths
                                                                        through the data set. Hence the exploration is independent from
3. RELATED WORK                                                         one end user to another and this allows users to derive personal
Interaction, exploration and visual storytelling are important          conclusions.
aspects of presentation in information visualization as they allow      From the analysis above, it can be seen that VisEN progresses the
users to gain a deeper understanding of data. This section analyses     state-of-the-art by introducing three novel factors which focus on
the state of the art to determine how adequately generating             allowing end users to: 1) explore related data through exploration
dynamic visual narratives and enabling personalized visual              paths; 2) view visual narratives; and 3) analyze tailored
explorations of these narratives have been addressed.                   exploration paths.
Visual narratives have been effectively used in journalism [9, 15,
24] to tell stories with data. These have ranged from presenting        4. IMPLEMENTATION OVERVIEW
several visualizations with annotations in one view to slides           The VisEN architecture uses principles discussed in 1) the
containing interactive visualizations to tell a story. Contextifier     visualization pipeline [6]; 2) the visual information seeking
[15] for example, provides visualizations embedded in news              mantra [25]; 3) the Template Editor and Shelf Configuration
articles and provides visualizations of related articles allowing       visual interface design approaches [13]; and 4) sequencing in
users to navigate and explore these. Tools such as Gapminder            visual narratives [14] to generate explorable personalized visual
[22], GED Viz [8] and SketchStory [18] provide users with               narratives. Figure 2 shows VisEN architecture, which consists of
interactive visual storytelling. However, the interactions are          the Narrative Builder, the Visualization Engine and the Visual
limited to hovering the mouse over data points to reveal details        Narrative Explorer components.
and filtering regions of the data. StoryFlow [19] allows users to
explore data in a second layer of the story through its bundling
operation, which reveals a level of detail beneath a bundled line.      4.1 Narrative Builder
Spotfire [27] provides users with data drill down capabilities,         The Narrative Builder enables narrative composers to easily
where visual structures can be clicked by users and the system          construct narratives from complex data. Visualizations are not
loads another visualization that also provides a drill down of the      introduced into the narrative during the narrative building phase.
data. A user can choose to drill down further and view the
                                                                      4.2 Visualization Engine
                                                                      The Visualization Engine transforms narratives into visual
                                                                      narratives by mapping data slices from the narrative to
                                                                      visualization techniques.

                                                                      4.2.1 Query Builder
                                                                      The Query Builder uses the data and metadata provided by the
                                                                      narratives composers in the data slices to generate and execute
                                                                      SQL queries against the specified data sources. The query results
                                                                      are formatted by data type, size (data sizes and number of series of
                                                                      data) and coordinates (data points) to aid the Rules Engine in
                                                                      selecting appropriate visualizations for the data slice.

                                                                      4.2.2 Rules Engine
                                                                      The Rules Engine uses the formatted query results and the data
                                                                      slice metadata to determine appropriate visualization techniques
                                                                      for each data slice of the narrative. Instead of building
                                                                      visualizations, VisEN utilizes JavaScript visualization libraries to
                 Figure 2. VisEN Architecture                         source visualization techniques. Extensive research [4, 5, 7, 12]
                                                                      has evaluated the affordances and characteristics of visualization
4.1.1 Data Connection Component                                       techniques and compared the suitability of various techniques for
Narrative Composers use the Data Connection component to              data sets. This research has been used by VisEN to allow
connect to heterogeneous data sources to construct narratives.        developers to build matrices that specify the characteristics,
Data connections are established by selecting data sources or         affordances and constraints of the supported visualizations. The
specifying connection parameters. Preconfigured data source           matrices are stored as XML files and new visualizations can be
parameters are stored in configurations files and new data source     seamlessly incorporated into the framework by creating a new
parameters supplied by narrative composers are also saved to          XML file (matrix) and importing the JavaScript library.
these files.
                                                                      4.2.3 Visualization Builder
4.1.2 Data Analysis Interface                                         The current set of visualization techniques supported by VisEN
Data slices form the individual pieces of narratives and are          requires data to be formatted as JSON objects. The Visualization
constructed by the narrative composers via the web based Data         Builder creates JSON objects using the query results and metadata
Analysis Interface. In addition to constructing the data slice, the   and populates the set of visualization techniques (currently nine
Data Analysis Interface allows narrative composers to analyze         techniques are supported including: bar chart, bubble chart,
data sources. The interface consists of a number of buttons which     gauge, line chart, pie chart, scatterplot, stacked bar chart, area
run general queries such as “select count..”, “select ..”      chart and parallel coordinates). It also makes the populated set of
etc.; this simplifies the process of constructing narratives as the   visualizations available to the narrative composer to view through
raw data values can be analyzed by narrative composers. The Data      a web interface as a dropdown list, where visualizations can be
Analysis Interface uses the jQuery Accordion widget to show           removed from the set. The remaining set is used for the visual
source tables and fields and uses the jQuery Draggable widget to      narrative.
facilitate dragging and dropping of data fields to construct data
slices. The interface provides a canvas with panels for fields and
filters. The data fields from the Draggable widget can be dropped     4.3 Visual Narrative Explorer
onto these panels to construct data slices. The drag and drop         The Visual Narrative Explorer personalizes the visual narratives
design approach has been used effectively in state of the art [26].   for end users by generating tailored exploration paths for each
When a field is dropped onto a filter panel, VisEN runs queries to    narrative based on individual preferences. It provides a web-based
fetch data to allow narrative composers to specify which values to    interface where end users can analyze visual narratives and view
use in the filter.                                                    exploration paths to understand data.

4.1.3 Encoded Exploration                                             4.3.1 Personalization Engine
An important and novel aspect of VisEN is exploration paths,          The Encoded Exploration component generates derivatives from
which are automatically constructed and connected to data slices.     data slices for exploration paths, which can be accepted or
Exploration paths consist of a series of visualizations linked to     rejected by the narrative composer. Accepted derivate data slices
each data slice or section of the narrative. End users can view and   and data slices related to the narrative are used to form
analyze exploration paths by clicking on elements in a data slice     personalized exploration paths. The Personalization Engine
to drill down into sections of a narrative or explore related items   personalizes the exploration paths using user data preferences, set
to obtain a deeper understanding of the data. Exploration paths       in the user model. These preferences are set when end users asked
are constructed by VisEN using data slices that have common           to select data tags (taken from data slice metadata) they are
elements or derivatives in the narrative. The narrative composer      interested in exploring when viewing visual narratives. Selected
can view the automatically constructed exploration paths and can      tags are stored in the VisEN user model and these are used to
remove and visualization to the path via the available add/remove     personalize the exploration path.
options on the Data Analysis Interface.
4.3.2 Narrative Dashboard                                               to predict how long it will take her to complete her next five
Published visual narratives are made available to end users             activities. Michelle now feels motivated and determined to work
through the web based Narrative Dashboard. End users are                hard and obtain a good grade. As she completes each activity, she
presented with the first data slice of visual narratives and the        explores her visual narratives and estimates the time the next
remaining data slice can be access by clicking the titles at top of     activity would take.
the interface. When an end user wishes to explore an element in
the data slice, she can click it and this generates the first           6. EVALUATION
visualization in exploration path, which is shown in a popup            VisEN was deployed to the AMAS [20] PLE during the 2013-
window on the web browser. Clicking an element in the visual            2014 academic year to provide learners with personalized visual
narrative fires an AJAX request and the linked exploration path is      narratives to allow them to analyze their engagement score, view
made available to the end user. At any point the end users can          time spent on activities and analyze peer comparisons. AMAS
close the exploration path popup window and continue analyzing          provides a dynamic and adaptive framework for composition and
the visual narrative or alternatively continue with the exploration.    assignment of personalized learning activities [20]. It has been
                                                                        used over the past three years to deliver an SQL database course
5. USE CASES                                                            to final year university students in Trinity College Dublin. Two
This section discusses two use cases; the first use case describes a    evaluations were carried out in conjunction with the delivery of
university professor using VisEN to construct two narratives. The       the AMAS SQL course. The first evaluation involved a university
second use case describes a student using personalized visual           professor using VisEN to construct visual narratives for his
narratives to understand and improve her course engagement.             students. The second evaluation involved participating students of
                                                                        the course using personalized visual narratives in order to
5.1 Use Case One – University Professor                                 understand their performance and engagement from their log data.
John is a Professor lecturing Database Management System to
final year university students. His students need to use the AMAS       6.1 Evaluating the Narrative Builder
[20] portal to study SQL. John understands the challenges               In this evaluation, the professor whose students worked through
learners’ have engaging with online learning modules and wishes         the AMAS activities, assumed the role of a narrative composer
to provide visual narratives to improve engagement by allowing          and constructed narratives using the AMAS log data from the
them to visually analyze and explore their individual log data.         2012-2013 academic year. The aim of this trial was to evaluate the
John logs into VisEN and assumes the role of a narrative                end to end tasks of the narrative composer: analyze a complex
composer. He connects to the AMAS data source containing                data set; construct narratives with exploration paths; and critique
learner log data from the last time the course was run. This data       the set of generated visualizations. The professor was provided
source consists of thousands of entries with all the interactions       with a 15 minutes training session on how to use the Narrative
learners had with the course over a three months period. After          Builder and then asked to construct the two narratives using the
analyzing the data he wishes to construct two narratives. He starts     Narrative Builder (shown on the left of figure 3): 1) A narrative
constructing data slices by dragging data fields onto the Narrative     showing learners’ engagement score and how it was calculated; 2)
Builder interface.. He clicks on the "Visualize Data" button and        A narrative presenting the time learners spent on activities, and
views the set of visualizations for each data slice and also views      allowing learners to compare activity times with their peers.
the automatically generated exploration paths. Finally he               Exploration paths were automatically generated, which showed a
disassociates the narrative with the previous log data and connects     breakdown of selected students' engagement score (drill down).
it to new data source (this consists of test entries as the course is   The other exploration path showed engagement scores of similar
yet to commence) and publishes the narratives.                          students (related data). Once both narratives were completed
                                                                        (which took 25 minutes with some assistance), the professor was
5.2 Use Case Two – Final Year Student                                   asked to interact with the visual narratives, which were
Michelle is a final year Computer Science student and has               automatically generated and analyze the data through exploration
received an average grade of below 50% each year during the first       paths. During the analysis, he was asked to answer questions by
three years of her course. However, she is determined to improve        exploring and interacting with the visual narratives, which he did
her grade in her final year. As part of one of her modules she          with ease and answered all the questions.
needs to study SQL using the AMAS portal. During the first               His final task was to critique the visualizations and the process of
month of the three month module, Michelle has occasionally used         constructing the narrative through a questionnaire and interview.
the portal. At the end of this month she receives a notification        The questionnaire focused on how useful the professor found the
from the portal informing her of her poor engagement with course        process of constructing narratives and analyzing exploration
activities and advises her that in previous years the students who      paths. For example, one of the questions asked: "When viewing
continued to engage at this level performed poorly.                     course engagement by activity, how useful was it to view students
Following on from this notification, Michelle wants to understand       with similar engagement through an exploration path”. The
how she can improve her engagement and estimate how much                questions also addressed how well the framework and
time she must commit to this module to perform well. She views          visualizations met his needs, such as “Did the framework support
her personalized visual narratives and analyzes her engagement          you in telling the story you wanted to tell” and “Where you ever
score and how it was calculated. She analyzes peer engagement           frustrated with the limitations of the user interface”, to which he
comparisons using her visual narratives which allow her to              offered useful suggestions such as providing tooltips and help
determine how to improve engagement. By analyzing peer                  options. From the feedback the professor found exploration paths
comparisons and exploring her visual narratives, Michelle is able       very useful for gaining insight and was able to tell the story
  Figure 3. Narrative Builder Interface (left) and two sample visualizations from a Personalized Student Visual Narrative (Right)
requested. He expressed that the data slices and resulting             narratives), these learners frequently returned to view their
visualizations represented his needs quite well. In the interview,     personalized visual narratives. Hence, it can be concluded that the
the professor expressed that he was able to follow and interact        personalized visual narratives assisted these learners in gaining a
with the visualizations easily and expressed confidence in             deeper knowledge of their performance data.
constructing data slices and building the narratives. Examining
                                                                       The second study analyzed if there was a correlation between
the time taken to learn and construct the narratives, it was evident
                                                                       weaker students interacting with their visual narratives and an
that the professor had a very positive experience constructing
                                                                       improvement in engagement. The log data of the 17 weaker
narratives using the Narrative Builder.
                                                                       students, who showed engagement improvement following a
                                                                       below average engagement notification, was analyzed. It was
6.2 Evaluating Personalized Visual Narratives                          found that all of these learners showed a minimum of a 70%
One of the primary aims of AMAS is to support weaker students          increase in interactions with their visual narratives during the
completing their course. The second evaluation focused on              period in which their engagement improved. From this, it was
analyzing the impact the personalized visual narratives had on         concluded that weaker students who increased in interactions with
supporting weaker learners to improve course engagement. The           their personalized visual narratives showed an improvement in
right hand side of Figure 3 shows two visualizations from one of       their course engagement level.
the narratives presented to learners. 108 students participated in
the AMAS SQL course; 22 of these were identified as weak
students as they had an average grade of below 50% for each of
                                                                       7. CONCLUSIONS AND FUTURE WORK
                                                                       This paper introduced VisEN as a framework to construct visual
the previous three years of their course.
                                                                       narratives and facilitate personalized visual explorations by
During the course, AMAS sent fortnightly notifications to learners     allowing end users to: 1) explore related data; 2) analyze visual
informing them of their engagement levels. The first study             narratives; and 3) analyze personalized exploration paths.
analyzed the AMAS log data, (consisting of thousands of entries        Two evaluations were carried out; the first evaluation involved a
for three months of interactions from 108 learners), and found that    university professor analyzing the log data of his students' course
all of the weaker students had at some stage received a below          activities and constructing visual narratives. The results of this
average engagement notification. The analysis of the log data of       evaluation were positive, with the professor confidently creating
the 22 weaker students found that 17 of these students showed an       data slices and narratives and positively commenting on his
improvement in engagement following this notification. It was          experience of executing the tasks required. The second evaluation
found that 14 of these 17 learners were immediately drawn to           involved analyzing the log data of weaker students who
their personalized visual narrative following a below average          participated in an online SQL course. This evaluation found that
engagement notification. All of these 14 learners executed a           the personalized visual narratives assisted these learners in
minimum of 45% of their total narrative interactions on the first      understanding and improving their engagement and performance
day after reading the notification. Following this notification        data.
(which did not explicitly direct them to their personalized visual
Preliminary results have been obtained from both evaluations.          [12] Graham M. and Kennedy J. 2010. A survey of multiple tree
Further work is required to evaluate the Narrative Builder through          visualization. Information Visualization 9, 4 (Dec. 2010),
qualitative and quantitative analysis using several users. In the           235–252. DOI= 10.1057/ivs.2009.29
2014 - 2015 academic year, it is intended to continue to provide       [13] Grammel, L., Bennett, C., Tory, M., & Storey, M. A. 2013.
learners with personalized visual narratives and compare                    A Survey of Visualization Construction User Interfaces. In
engagement results with control groups, and quantify the increase           EuroVis-Short Papers (pp. 19-23). The Eurographics
in engagement levels, and verify the statistical significance.              Association.
                                                                       [14] Hullman J1, Drucker S, Henry Riche N, Lee B, Fisher D,
8. ACKNOWLEDGMENTS                                                          Adar E. 2013. A deeper understanding of sequence in
This research is supported by the Science Foundation Ireland
                                                                            narrative visualization. IEEE Trans Vis Comput Graph. 19,
(Grant 12/CE/I2267) as part of CNGL (www.cngl.ie) at Trinity
                                                                            12 (Dec 2013), 2406-15. DOI= 10.1109/TVCG.2013.119.
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                                                                       [15] Hullman, J., Diakopoulos, N. and Adar, E. 2013.
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