<!DOCTYPE article PUBLIC "-//NLM//DTD JATS (Z39.96) Journal Archiving and Interchange DTD v1.0 20120330//EN" "JATS-archivearticle1.dtd">
<article xmlns:xlink="http://www.w3.org/1999/xlink">
  <front>
    <journal-meta />
    <article-meta>
      <title-group>
        <article-title>Comparing Ebook Student Interactions With Test Scores: A Case Study Using CSAwesome</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>Hisamitsu Maeda</string-name>
          <email>himaeda@umich.edu</email>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Barbara Ericson</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Paramveer Dhillon</string-name>
          <email>dhillonp@umich.edu</email>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <aff id="aff0">
          <label>0</label>
          <institution>University of Michigan</institution>
          ,
          <addr-line>Ann Arbor, MI</addr-line>
          ,
          <country country="US">USA</country>
        </aff>
      </contrib-group>
      <abstract>
        <p>Interactive ebooks have better learning gains than static ebooks, students prefer them, and more computing courses are using interactive ebooks. The number of computing ebooks on the open-source Runestone interactive ebook platform increased from one in 2011 to over 30 in 2020. Runestone currently serves over two million page views a week. It includes books for CS0, CS1, CS2, data science, and web development and supports coding in Java, Python, and C++. The ebooks include instructional material: text, images, videos, and interactive practice problems with immediate feedback: multiple-choice, ll-in-the-blank, write code (active code), mixed-up code (Parsons), clickable code, and matching. User interaction with the ebooks is timestamped and logged. This information includes page views, video plays, video completion, Parsons moves, problem answers, and learner written code. This ne grained data may help us automatically identify struggling students. This paper reports on several analyses comparing student activities to the midterm score from one of the Runestone ebooks, CSAwesome. Speci cally, we compared the major types of log le entries to the midterm score and also conducted an in-depth analysis of mixed-up code (Parsons) problem data.</p>
      </abstract>
      <kwd-group>
        <kwd>eol&gt;e-book</kwd>
        <kwd>data mining</kwd>
        <kwd>Parsons problem</kwd>
      </kwd-group>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>1. INTRODUCTION</title>
      <p>
        Research has shown that interactive ebooks have better
learning gains than static ebooks [
        <xref ref-type="bibr" rid="ref20">20</xref>
        ]. In addition, most students
report that the interactive features help them learn and want
to use interactive ebooks in future courses [
        <xref ref-type="bibr" rid="ref15">15</xref>
        ]. A 2013
working group predicted that traditional CS textbooks would be
replaced by interactive ebooks [
        <xref ref-type="bibr" rid="ref13">13</xref>
        ].
      </p>
      <p>
        Runestone is an open-source ebook platform that has grown
from serving one interactive ebook [
        <xref ref-type="bibr" rid="ref15">15</xref>
        ] in 2011 to over 30
free ebooks in 2021. It supports several languages, including
Copyright ©2021 for this paper by its authors. Use permitted under
Creative Commons License Attribution 4.0 International (CC BY 4.0)
Python, Java, C++, and SQL [
        <xref ref-type="bibr" rid="ref10">10</xref>
        ]. During the 2020-21
academic year, Runestone had 69,400 registered users and
served an average of over two million page views a weeks.
Runestone interactive ebooks log timestamped user
interactions1. For the analyses in this paper, we use the
CSAwesome interactive ebook. CSAwesome has been endorsed by
the College Board for the Advanced Placement (AP)
Computer Science A (CSA) course [
        <xref ref-type="bibr" rid="ref4">4</xref>
        ]. Advanced Placement
courses are taken by secondary students for college credit
and/or placement. The AP CSA course is equivalent to a
rst course for majors (CS1) at the college level and
covers object-oriented programming in Java. Our CSAwesome
data is from custom courses. Instructors can create a
custom course for any of the free ebooks on Runestone and have
their students register for that custom course.
      </p>
      <p>
        Interactive ebooks provide rich data that could be
leveraged to improve instruction [
        <xref ref-type="bibr" rid="ref23">23</xref>
        ]. We may be able to
identify struggling students in order to provide help. Our
research questions were 1) what student activities correlate
with scores on the midterm and 2) what Parsons problem
activities correlate with the midterm score? To answer these
questions, we performed regression analyses at both the higher
level based on the major types of activities and at the lower
level with a more in-depth analysis of Parsons problem data.
      </p>
    </sec>
    <sec id="sec-2">
      <title>2. RELATED WORK</title>
      <p>
        We are interested in the relationship between students'
activities in the ebook and their pretest and midterm scores.
In a related study, Pollari-Malmi et al. [
        <xref ref-type="bibr" rid="ref20">20</xref>
        ] found an
increase in use, motivation, and learning gains from use of an
interactive ebook versus an equivalent static ebook. Ericson
et al. [
        <xref ref-type="bibr" rid="ref6">6</xref>
        ] found that teachers who used more of the
interactive features in an ebook had higher gains in con dence and
higher scores on the nal posttest. Parker et al. [
        <xref ref-type="bibr" rid="ref18">18</xref>
        ] found
that students and teachers used an interactive ebook di
erently with teachers showing more characteristics of expert
learners. Akcap nar et al. [
        <xref ref-type="bibr" rid="ref1">1</xref>
        ] used student reading behavior
in an ebook to predict at-risk students. Park et al. [
        <xref ref-type="bibr" rid="ref17">17</xref>
        ] used
statistical change detection techniques to detect changes in
student behavior from clickstream data in a Learning
Management System (LMS). They found that students who
increased their reviewing activity relative to other students in
the course had a higher probability of passing the course.
1Researchers can request an anonymized log le from Brad
Miller, the founder of Runestone.
      </p>
      <p>
        Several researchers [
        <xref ref-type="bibr" rid="ref19 ref2 ref21 ref22 ref24 ref3 ref9">3, 24, 21, 22, 9, 19, 2</xref>
        ] have been
exploring Parsons problems as both an alternative to writing
code from scratch and as a summative assessment. In
Parsons problems learners must place mixed-up blocks of code
in the correct order. They may also have to correctly
indent the blocks. Parsons problems can also have
distractors, which are code blocks that are not needed in a correct
solution. Helminen et al. [
        <xref ref-type="bibr" rid="ref12">12</xref>
        ] visualized students'
problemsolving process on Parsons problems using a graphical
representation. They detected several di erent approaches to
solving Parsons problems including top-down, control
structures rst, and trial and error. Some learners got stuck in
circular loops and repeated the same incorrect solution.
Ericson et al. [
        <xref ref-type="bibr" rid="ref8">8</xref>
        ] found that more learners attempted Parsons
problems than nearby multiple-choice questions in an
interactive ebook. Maharjan et al. [
        <xref ref-type="bibr" rid="ref14">14</xref>
        ] proposed an edit distance
trail to show students' solution paths in Parsons problems in
a simpler fashion than a graphical representation. They also
discussed potential issues with studying Parsons problems
using descriptive statistics methods. Morrison et al. [
        <xref ref-type="bibr" rid="ref16">16</xref>
        ]
found that subgoal labels help students solve Parsons
problems. Du et al. [
        <xref ref-type="bibr" rid="ref3">3</xref>
        ] conducted a review of recent studies on
Parsons problems.
      </p>
      <p>
        Ericson invented two types of adaptation for Parsons
problems [
        <xref ref-type="bibr" rid="ref5 ref7">7, 5</xref>
        ]. In intra-problem adaptation the problem can
be dynamically made easier by removing a distractor,
providing indentation, or combining two blocks into one. The
adaptation is triggered by clicking a "Help" button. In
interproblem adaptation the di culty of the next problem is
automatically modi ed based on the learner's performance on
the last problem. The problem can be made easier by pairing
distractor and correct code blocks or by removing
distractors. It can be made more di cult by using all distractors
and randomly mixing the distractor blocks in with the
correct code blocks. Learners are nearly twice as likely to
correctly solve adaptive Parsons problems than non-adaptive
ones and report that solving Parsons problems helps them
learn to x and write code [
        <xref ref-type="bibr" rid="ref5">5</xref>
        ]. A randomized controlled
study provided evidence that solving adaptive Parsons
problems takes signi cantly less time than writing the equivalent
code and with similar learning gains from pretest to posttest
[
        <xref ref-type="bibr" rid="ref7">7</xref>
        ].
      </p>
    </sec>
    <sec id="sec-3">
      <title>3. DATASET</title>
      <p>
        The log le used in our analysis comes from the CSAwesome
interactive ebook on the open-source Runestone platform.
This book was revised by Beryl Ho man of Elms College
and the Mobile CSP project in 2019 for the 2019 AP CS
A exam [
        <xref ref-type="bibr" rid="ref4">4</xref>
        ]. The log includes page views, video interaction,
and the results from interactive practice problems:
multiplechoice, write code (active code), and mixed-up code (Parsons
problems).
      </p>
      <p>
        An active code is a traditional programming exercise in
which students write/edit/run code in the ebook. Many
active code exercises have unit tests that students can use
to verify that their code is correct. Students can also use
a slider to view previous versions of the code. The \Show
CodeLens" button on the active code will display a program
visualizer (CodeLens), allowing students to step through
their code line by line and visualize the variables. It is a
version of Python Tutor [
        <xref ref-type="bibr" rid="ref11">11</xref>
        ]. A Parsons problem provides
mixed-up code blocks that the learner must place in the
correct order [
        <xref ref-type="bibr" rid="ref19">19</xref>
        ] as shown in Figure 1. The Parsons problems
in this ebook were adaptive. While some adaptive systems
use selection adaptation in which the next problem is
selected from a set of possible problems based on the learner's
performance, this system modi es the di culty of the
current or next problem in the ebook based on the learner's
performance.
      </p>
      <p>
        We analyzed ve categories of log le entries: page views,
video (play, pause, and completion), active code
interaction (run, edit, slide, and unit test), Parsons problem block
moves and answers, and answers to multiple-choice
questions. Overall, the log le contained data from 1,893
students in 57 custom classes. Most of these were high school
classes, but some of them were college classes. This paper
analyzed a subset of the log data from 505 students who took
both the pretest and midterm in their course. The summary
statistics of the data are shown in Table 1. Over 37% of the
log le activities were interaction with active code. This
included running the code, editing the code, sliding the history
to view di erent versions of the code, and running unit tests.
The AP CSA exam includes 40 multiple-choice questions and
four free response questions where the student must write
Java code to solve a problem. The ebook is broken into
10 content-based units and ve practice units. At the end
of each content-based unit there are at least 10
multiplechoice questions, mixed-up code (Parsons) problems, and
write code problems [
        <xref ref-type="bibr" rid="ref4">4</xref>
        ].
      </p>
      <p>We were also interested in the e ect of class size on students'
performance. For this analysis, we divided the students into
two groups: classes with less than 30 students, which is the
typical maximum class size in high school, and classes with
more than 30 students|224 students were in large classes,
and 281 were in small classes.</p>
    </sec>
    <sec id="sec-4">
      <title>4. METHODOLOGY</title>
    </sec>
    <sec id="sec-5">
      <title>4.1 Regression analysis of student activities</title>
      <p>In this section, we analyze the impact of student activities on
student performance. First, we explore the data and check
the relationship between di erent student activities.
Figure 2 shows that the percentage correct on the midterm has
a positive correlation with the percentage of correct for each
activity. Multiple-choice problems have the highest
correlation with the midterm. This could be because the midterm
is a set of 20 multiple choice questions. On the other hand,
there is a negative correlation between the midterm and the
number of some other activities (i.e. the number of times
that CodeLens was used and the percent of videos that were
completed).</p>
      <p>Next, we employ a linear regression model to this data with
the percentage of correct answers on the midterm exam as
the dependent variable. The count and type of student
activities were used as independent variables. Since the
activity variables have a skewed distribution, we log-transformed
them as x ! log(x + 1) and standardized them before
running the regression analysis. Also, since there is a di erence
in the test results based on the class size (as can be seen
from Figure 3), we add the class size as a dummy variable
in our regression model. The regression results are shown in
Table 2.</p>
      <p>The percent correct on the midterm was negatively
correlated with being in a larger class, perhaps because there
is less one-on-one interaction with the instructor and, as
a result, lower learning outcomes. Midterm results were
also negatively correlated with the number of interactions
with the CodeLens and the number of videos completed.
This may indicate that both of these activities were more
likely to be used by struggling students. Midterm results
were positively correlated with the percent correct on the
pretest, percentage correct on other multiple-choice
questions, the number of page views, and the number of videos
played. It is interesting that the midterm score is positively
correlated with the number of videos played, but negatively
correlated with the number of videos completed. It could
be that stronger students watch a video till they nd what
they need and then quit.</p>
    </sec>
    <sec id="sec-6">
      <title>4.2 Regression Analysis of Parsons Problems</title>
      <p>In this section, we conduct an in-depth analysis of Parsons
problems. As described earlier, these Parsons problems used
both intra-problem and inter-problem adaptation. In
intraproblem adaptation, if a student submits at least three
incorrect solutions, they are noti ed that they can use a \Help"
button to make the problem easier. Each time the student
clicks the \Help" button, the ebook will remove a distractor
block from the solution, provide the indentation, or combine
two blocks into one, hence providing an implicit hint.
First, we pre-process the log data to gather detailed
information on the Parsons interactions. As shown in Figure 4,
students have to move from a state where all the blocks are
jumbled to the state in which all the blocks are placed
correctly. The nal state is the correct solution. We count
each step taken by the students and the number of failures
incurred until a student nds the correct ordering. We count
the number of times a student got help (clicked the \Help"
button). We also count the number of steps and time until
a student asked for help. In order to tease apart the e ect
of \getting help," we add an interaction term with the \help
ag" in our regression.</p>
      <p>The regression result is shown in Table 3. As can be seen
from the result, being in a large class is negatively related
to the midterm score, as we found in our previous regression
analysis. We also found that the number of steps before a
student got help from the software was positively correlated
with the midterm test results. This could be because the
students who received help from the software after
performing more correct steps were more motivated to succeed in
the course in the rst place. In other words, stronger
student learners could gure out more of the problem before
they asked for help. On the other hand, the time taken to
get support was negatively associated with the test score.
This implies that students who took too long to get support
scored poorly on the midterm. In addition, students who
received more support, i.e., received more help, did not score
as well on the midterm.
Next, for a particular problem that the learners solved,
drawing a sideways L with a turtle in Unit 2 as shown in Figure1,
we also analyzed the number of block moves and the time
elapsed before the learner found the correct answer for each
problem. As discussed earlier, we counted the number of
steps it took from the initial state to the correct order. We
de ne \extra steps" as the number of code-block moves
beyond the required number of moves to a correct answer.
For example, if a solution can be reached in just 10 steps,
and a student took 12 steps, this would be two extra steps.
Additionally, we also measured the amount of time it took
students to correct the jumbled code blocks in the Parsons
problem. Figure 5 shows the number of extra steps taken as
a function of the time taken for students in both large and
small classes.</p>
    </sec>
    <sec id="sec-7">
      <title>5. LIMITATIONS</title>
      <p>The log le data was from a random selection of custom
courses on the Runestone platform. We do not have any
additional information about these courses, such as which
items were assigned, nal grades, or student demographics.
In the summer of 2021 we will be receiving log le data for
this same ebook from teachers who attended professional
development with the Mobile CS Team. That data should
allow for a more in-depth analysis.</p>
    </sec>
    <sec id="sec-8">
      <title>6. CONCLUSION</title>
      <p>In this paper, we performed several quantitative analyses
on the clickstream data from student interaction with the
CSAwesome ebook. We analyzed the relationship between
students' activities on the ebook and their midterm scores.
We found several positive and negative correlations. In a
regression analysis the most highly weighted variable with
a positive correlation was the percentage correct on other
multiple choice questions and most highly weighted variable
with a negative correlation was being in a large class.
We also analyzed the learner interaction patterns on the
mixed-code (Parsons) problems. Speci cally, we examined
the impact of the number of steps taken, time taken, as well
as the frequency of help on the students' midterm scores.
The results show a positive association between the number
of correctly completed Parsons problems and the learners'
midterm scores. Further, there was a negative association
between the midterm scores and the time the learner took to
get help on a Parsons problem as well as a negative
association between the class size and the midterm score. A close
look at two Parsons problems showed a negative correlation
with the number of extra steps and time to solve a Parsons
problem and the midterm score.</p>
      <p>While our analyses uncover subtle patterns in students'
interactions with the CSAwesome ebook, it will be interesting
to test the robustness of our ndings and see if they
generalize to other interactive ebook platforms or across
different programming courses, e.g., C++ or Python. If
Parsons problems can help detect struggling students early in
a course it may be possible to intervene to improve student
performance.</p>
    </sec>
  </body>
  <back>
    <ref-list>
      <ref id="ref1">
        <mixed-citation>
          [1]
          <string-name>
            <given-names>G.</given-names>
            <surname>Akcap nar</surname>
          </string-name>
          ,
          <string-name>
            <given-names>M. N.</given-names>
            <surname>Hasnine</surname>
          </string-name>
          ,
          <string-name>
            <given-names>R.</given-names>
            <surname>Majumdar</surname>
          </string-name>
          ,
          <string-name>
            <given-names>B.</given-names>
            <surname>Flanagan</surname>
          </string-name>
          , and
          <string-name>
            <given-names>H.</given-names>
            <surname>Ogata</surname>
          </string-name>
          .
          <article-title>Developing an early-warning system for spotting at-risk students by using ebook interaction logs</article-title>
          .
          <source>Smart Learning Environments</source>
          ,
          <volume>6</volume>
          (
          <issue>1</issue>
          ):
          <fpage>4</fpage>
          ,
          <year>2019</year>
          .
        </mixed-citation>
      </ref>
      <ref id="ref2">
        <mixed-citation>
          [2]
          <string-name>
            <given-names>P.</given-names>
            <surname>Denny</surname>
          </string-name>
          ,
          <string-name>
            <given-names>A.</given-names>
            <surname>Luxton-Reilly</surname>
          </string-name>
          , and
          <string-name>
            <given-names>B.</given-names>
            <surname>Simon</surname>
          </string-name>
          .
          <article-title>Evaluating a new exam question: Parsons problems</article-title>
          .
          <source>In Proceedings of the fourth international workshop on computing education research</source>
          , pages
          <volume>113</volume>
          {
          <fpage>124</fpage>
          ,
          <year>2008</year>
          .
        </mixed-citation>
      </ref>
      <ref id="ref3">
        <mixed-citation>
          [3]
          <string-name>
            <given-names>Y.</given-names>
            <surname>Du</surname>
          </string-name>
          ,
          <string-name>
            <given-names>A.</given-names>
            <surname>Luxton-Reilly</surname>
          </string-name>
          , and
          <string-name>
            <given-names>P.</given-names>
            <surname>Denny</surname>
          </string-name>
          .
          <article-title>A review of research on parsons problems</article-title>
          .
          <source>In Proceedings of the Twenty-Second Australasian Computing Education Conference</source>
          , ACE'
          <volume>20</volume>
          , page
          <volume>195</volume>
          {
          <fpage>202</fpage>
          , New York, NY, USA,
          <year>2020</year>
          .
          <article-title>Association for Computing Machinery</article-title>
          .
        </mixed-citation>
      </ref>
      <ref id="ref4">
        <mixed-citation>
          [4]
          <string-name>
            <given-names>B.</given-names>
            <surname>Ericson</surname>
          </string-name>
          ,
          <string-name>
            <surname>B.</surname>
          </string-name>
          <article-title>Ho man, and</article-title>
          <string-name>
            <given-names>J.</given-names>
            <surname>Rosato</surname>
          </string-name>
          . Csawesome:
          <article-title>Ap csa curriculum and professional development (practical report)</article-title>
          .
          <source>In Proceedings of the 15th Workshop on Primary and Secondary Computing Education, WiPSCE '20</source>
          , New York, NY, USA,
          <year>2020</year>
          .
          <article-title>Association for Computing Machinery</article-title>
          .
        </mixed-citation>
      </ref>
      <ref id="ref5">
        <mixed-citation>
          [5]
          <string-name>
            <given-names>B.</given-names>
            <surname>Ericson</surname>
          </string-name>
          ,
          <string-name>
            <given-names>A.</given-names>
            <surname>McCall</surname>
          </string-name>
          , and
          <string-name>
            <given-names>K.</given-names>
            <surname>Cunningham</surname>
          </string-name>
          .
          <article-title>Investigating the a ect and e ect of adaptive parsons problems</article-title>
          .
          <source>In Proceedings of the 19th Koli Calling International Conference on Computing Education Research</source>
          , pages
          <volume>1</volume>
          {
          <fpage>10</fpage>
          ,
          <year>2019</year>
          .
        </mixed-citation>
      </ref>
      <ref id="ref6">
        <mixed-citation>
          [6]
          <string-name>
            <given-names>B.</given-names>
            <surname>Ericson</surname>
          </string-name>
          ,
          <string-name>
            <given-names>S.</given-names>
            <surname>Moore</surname>
          </string-name>
          ,
          <string-name>
            <given-names>B.</given-names>
            <surname>Morrison</surname>
          </string-name>
          , and
          <string-name>
            <given-names>M.</given-names>
            <surname>Guzdial</surname>
          </string-name>
          .
          <article-title>Usability and usage of interactive features in an online ebook for cs teachers</article-title>
          .
          <source>In Proceedings of the Workshop in Primary and Secondary Computing Education</source>
          , pages
          <volume>111</volume>
          {
          <fpage>120</fpage>
          ,
          <year>2015</year>
          .
        </mixed-citation>
      </ref>
      <ref id="ref7">
        <mixed-citation>
          [7]
          <string-name>
            <given-names>B. J.</given-names>
            <surname>Ericson</surname>
          </string-name>
          ,
          <string-name>
            <given-names>J. D.</given-names>
            <surname>Foley</surname>
          </string-name>
          , and
          <string-name>
            <given-names>J.</given-names>
            <surname>Rick</surname>
          </string-name>
          .
          <article-title>Evaluating the e ciency and e ectiveness of adaptive parsons problems</article-title>
          .
          <source>In Proceedings of the 2018 ACM Conference on International Computing Education Research</source>
          , pages
          <volume>60</volume>
          {
          <fpage>68</fpage>
          ,
          <year>2018</year>
          .
        </mixed-citation>
      </ref>
      <ref id="ref8">
        <mixed-citation>
          [8]
          <string-name>
            <given-names>B. J.</given-names>
            <surname>Ericson</surname>
          </string-name>
          ,
          <string-name>
            <given-names>M. J.</given-names>
            <surname>Guzdial</surname>
          </string-name>
          , and
          <string-name>
            <given-names>B. B.</given-names>
            <surname>Morrison</surname>
          </string-name>
          .
          <article-title>Analysis of interactive features designed to enhance learning in an ebook</article-title>
          .
          <source>In Proceedings of the eleventh annual International Conference on International Computing Education Research</source>
          , pages
          <volume>169</volume>
          {
          <fpage>178</fpage>
          ,
          <year>2015</year>
          .
        </mixed-citation>
      </ref>
      <ref id="ref9">
        <mixed-citation>
          [9]
          <string-name>
            <given-names>B. J.</given-names>
            <surname>Ericson</surname>
          </string-name>
          ,
          <string-name>
            <given-names>L. E.</given-names>
            <surname>Margulieux</surname>
          </string-name>
          , and
          <string-name>
            <given-names>J.</given-names>
            <surname>Rick</surname>
          </string-name>
          .
          <article-title>Solving parsons problems versus xing and writing code</article-title>
          .
          <source>In Proceedings of the 17th Koli Calling International Conference on Computing Education Research</source>
          , pages
          <volume>20</volume>
          {
          <fpage>29</fpage>
          ,
          <year>2017</year>
          .
        </mixed-citation>
      </ref>
      <ref id="ref10">
        <mixed-citation>
          [10]
          <string-name>
            <given-names>B. J.</given-names>
            <surname>Ericson</surname>
          </string-name>
          and
          <string-name>
            <given-names>B. N.</given-names>
            <surname>Miller</surname>
          </string-name>
          .
          <article-title>Runestone: A platform for free, on-line, and interactive ebooks</article-title>
          .
          <source>In Proceedings of the 51st ACM Technical Symposium on Computer Science Education</source>
          , pages
          <volume>1012</volume>
          {
          <fpage>1018</fpage>
          ,
          <year>2020</year>
          .
        </mixed-citation>
      </ref>
      <ref id="ref11">
        <mixed-citation>
          [11]
          <string-name>
            <given-names>P. J.</given-names>
            <surname>Guo</surname>
          </string-name>
          .
          <article-title>Online python tutor: embeddable web-based program visualization for cs education</article-title>
          .
          <source>In Proceeding of the 44th ACM technical symposium on Computer science education</source>
          , pages
          <volume>579</volume>
          {
          <fpage>584</fpage>
          ,
          <year>2013</year>
          .
        </mixed-citation>
      </ref>
      <ref id="ref12">
        <mixed-citation>
          [12]
          <string-name>
            <given-names>J.</given-names>
            <surname>Helminen</surname>
          </string-name>
          ,
          <string-name>
            <given-names>P.</given-names>
            <surname>Ihantola</surname>
          </string-name>
          ,
          <string-name>
            <given-names>V.</given-names>
            <surname>Karavirta</surname>
          </string-name>
          , and
          <string-name>
            <given-names>L.</given-names>
            <surname>Malmi</surname>
          </string-name>
          .
          <article-title>How do students solve parsons programming problems? an analysis of interaction traces</article-title>
          .
          <source>In Proceedings of the Ninth Annual International Conference on International Computing Education Research</source>
          , ICER '
          <volume>12</volume>
          , page
          <volume>119</volume>
          {
          <fpage>126</fpage>
          , New York, NY, USA,
          <year>2012</year>
          .
          <article-title>Association for Computing Machinery</article-title>
          .
        </mixed-citation>
      </ref>
      <ref id="ref13">
        <mixed-citation>
          [13]
          <string-name>
            <given-names>A.</given-names>
            <surname>Korhonen</surname>
          </string-name>
          ,
          <string-name>
            <given-names>T.</given-names>
            <surname>Naps</surname>
          </string-name>
          ,
          <string-name>
            <given-names>C.</given-names>
            <surname>Boisvert</surname>
          </string-name>
          ,
          <string-name>
            <given-names>P.</given-names>
            <surname>Crescenzi</surname>
          </string-name>
          ,
          <string-name>
            <given-names>V.</given-names>
            <surname>Karavirta</surname>
          </string-name>
          ,
          <string-name>
            <given-names>L.</given-names>
            <surname>Mannila</surname>
          </string-name>
          ,
          <string-name>
            <given-names>B.</given-names>
            <surname>Miller</surname>
          </string-name>
          ,
          <string-name>
            <given-names>B.</given-names>
            <surname>Morrison</surname>
          </string-name>
          ,
          <string-name>
            <given-names>R. R.</given-names>
            <surname>Rodger</surname>
          </string-name>
          ,
          <string-name>
            <surname>Susan</surname>
            <given-names>H</given-names>
          </string-name>
          ,
          <article-title>and</article-title>
          <string-name>
            <surname>A.</surname>
          </string-name>
          <article-title>Sha er, Cli ord. Requirements and design strategies for open source interactive computer science ebooks</article-title>
          .
          <source>In Proceedings of the ITiCSE working group reports conference on Innovation and technology in computer science education-working group reports</source>
          , pages
          <volume>53</volume>
          {
          <fpage>72</fpage>
          ,
          <year>2013</year>
          .
        </mixed-citation>
      </ref>
      <ref id="ref14">
        <mixed-citation>
          [14]
          <string-name>
            <given-names>S.</given-names>
            <surname>Maharjan</surname>
          </string-name>
          and
          <string-name>
            <given-names>A.</given-names>
            <surname>Kumar</surname>
          </string-name>
          .
          <article-title>Using edit distance trails to analyze path solutions of parsons puzzles</article-title>
          .
          <source>In EDM</source>
          ,
          <year>2020</year>
          .
        </mixed-citation>
      </ref>
      <ref id="ref15">
        <mixed-citation>
          [15]
          <string-name>
            <given-names>B. N.</given-names>
            <surname>Miller</surname>
          </string-name>
          and
          <string-name>
            <given-names>D. L.</given-names>
            <surname>Ranum</surname>
          </string-name>
          .
          <article-title>Beyond pdf and epub: toward an interactive textbook</article-title>
          .
          <source>In Proceedings of the 17th ACM annual conference on Innovation and technology in computer science education</source>
          , pages
          <volume>150</volume>
          {
          <fpage>155</fpage>
          ,
          <year>2012</year>
          .
        </mixed-citation>
      </ref>
      <ref id="ref16">
        <mixed-citation>
          [16]
          <string-name>
            <given-names>B. B.</given-names>
            <surname>Morrison</surname>
          </string-name>
          ,
          <string-name>
            <given-names>L. E.</given-names>
            <surname>Margulieux</surname>
          </string-name>
          ,
          <string-name>
            <given-names>B.</given-names>
            <surname>Ericson</surname>
          </string-name>
          , and
          <string-name>
            <given-names>M.</given-names>
            <surname>Guzdial</surname>
          </string-name>
          .
          <article-title>Subgoals help students solve parsons problems</article-title>
          .
          <source>In Proceedings of the 47th ACM Technical Symposium on Computing Science Education</source>
          , pages
          <volume>42</volume>
          {
          <fpage>47</fpage>
          ,
          <year>2016</year>
          .
        </mixed-citation>
      </ref>
      <ref id="ref17">
        <mixed-citation>
          [17]
          <string-name>
            <given-names>J.</given-names>
            <surname>Park</surname>
          </string-name>
          ,
          <string-name>
            <given-names>K.</given-names>
            <surname>Denaro</surname>
          </string-name>
          ,
          <string-name>
            <given-names>F.</given-names>
            <surname>Rodriguez</surname>
          </string-name>
          ,
          <string-name>
            <given-names>P.</given-names>
            <surname>Smyth</surname>
          </string-name>
          , and
          <string-name>
            <given-names>M.</given-names>
            <surname>Warschauer</surname>
          </string-name>
          .
          <article-title>Detecting changes in student behavior from clickstream data</article-title>
          .
          <source>In Proceedings of the Seventh International Learning Analytics amp; Knowledge Conference, LAK '17, page</source>
          <volume>21</volume>
          {
          <fpage>30</fpage>
          , New York, NY, USA,
          <year>2017</year>
          .
          <article-title>Association for Computing Machinery</article-title>
          .
        </mixed-citation>
      </ref>
      <ref id="ref18">
        <mixed-citation>
          [18]
          <string-name>
            <surname>M. C. Parker</surname>
            ,
            <given-names>K.</given-names>
          </string-name>
          <string-name>
            <surname>Rogers</surname>
            ,
            <given-names>B. J.</given-names>
          </string-name>
          <string-name>
            <surname>Ericson</surname>
            , and
            <given-names>M.</given-names>
          </string-name>
          <string-name>
            <surname>Guzdial</surname>
          </string-name>
          .
          <article-title>Students and teachers use an online ap cs principles ebook di erently: Teacher behavior consistent with expert learners</article-title>
          .
          <source>In Proceedings of the 2017 ACM Conference on International Computing Education Research</source>
          , pages
          <volume>101</volume>
          {
          <fpage>109</fpage>
          ,
          <year>2017</year>
          .
        </mixed-citation>
      </ref>
      <ref id="ref19">
        <mixed-citation>
          [19]
          <string-name>
            <given-names>D.</given-names>
            <surname>Parsons</surname>
          </string-name>
          and
          <string-name>
            <given-names>P.</given-names>
            <surname>Haden</surname>
          </string-name>
          .
          <article-title>Parson's programming puzzles: a fun and e ective learning tool for rst programming courses</article-title>
          .
          <source>In Proceedings of the 8th Australasian Conference on Computing Education-</source>
          Volume
          <volume>52</volume>
          , pages
          <fpage>157</fpage>
          {
          <fpage>163</fpage>
          ,
          <year>2006</year>
          .
        </mixed-citation>
      </ref>
      <ref id="ref20">
        <mixed-citation>
          [20]
          <string-name>
            <given-names>K.</given-names>
            <surname>Pollari-Malmi</surname>
          </string-name>
          ,
          <string-name>
            <given-names>J.</given-names>
            <surname>Guerra</surname>
          </string-name>
          ,
          <string-name>
            <given-names>P.</given-names>
            <surname>Brusilovsky</surname>
          </string-name>
          ,
          <string-name>
            <given-names>L.</given-names>
            <surname>Malmi</surname>
          </string-name>
          , and T. Sirkia.
          <article-title>On the value of using an interactive electronic textbook in an introductory programming course</article-title>
          .
          <source>In Proceedings of the 17th Koli Calling International Conference on Computing Education Research</source>
          , pages
          <volume>168</volume>
          {
          <fpage>172</fpage>
          ,
          <year>2017</year>
          .
        </mixed-citation>
      </ref>
      <ref id="ref21">
        <mixed-citation>
          [21]
          <string-name>
            <given-names>W.</given-names>
            <surname>Wang</surname>
          </string-name>
          ,
          <string-name>
            <given-names>R.</given-names>
            <surname>Zhi</surname>
          </string-name>
          ,
          <string-name>
            <given-names>A.</given-names>
            <surname>Milliken</surname>
          </string-name>
          ,
          <string-name>
            <given-names>N.</given-names>
            <surname>Lytle</surname>
          </string-name>
          , and
          <string-name>
            <given-names>T. W.</given-names>
            <surname>Price</surname>
          </string-name>
          . Crescendo:
          <article-title>Engaging students to self-paced programming practices</article-title>
          .
          <source>In Proceedings of the 51st ACM Technical Symposium on Computer Science Education</source>
          , pages
          <volume>859</volume>
          {
          <fpage>865</fpage>
          ,
          <year>2020</year>
          .
        </mixed-citation>
      </ref>
      <ref id="ref22">
        <mixed-citation>
          [22]
          <string-name>
            <given-names>N.</given-names>
            <surname>Weinman</surname>
          </string-name>
          ,
          <string-name>
            <given-names>A.</given-names>
            <surname>Fox</surname>
          </string-name>
          , and
          <string-name>
            <given-names>M. A.</given-names>
            <surname>Hearst</surname>
          </string-name>
          .
          <article-title>Improving instruction of programming patterns with faded parsons problems</article-title>
          .
          <source>In Proceedings of the 2021 CHI Conference on Human Factors in Computing Systems, CHI '21</source>
          , New York, NY, USA,
          <year>2021</year>
          .
          <article-title>Association for Computing Machinery</article-title>
          .
        </mixed-citation>
      </ref>
      <ref id="ref23">
        <mixed-citation>
          [23]
          <string-name>
            <given-names>H.</given-names>
            <surname>Yan</surname>
          </string-name>
          ,
          <string-name>
            <given-names>F.</given-names>
            <surname>Lin</surname>
          </string-name>
          , et al.
          <article-title>Including learning analytics in the loop of self-paced online course learning design</article-title>
          .
          <source>International Journal of Arti cial Intelligence in Education</source>
          , pages
          <volume>1</volume>
          {
          <fpage>18</fpage>
          ,
          <year>2020</year>
          .
        </mixed-citation>
      </ref>
      <ref id="ref24">
        <mixed-citation>
          [24]
          <string-name>
            <given-names>R.</given-names>
            <surname>Zhi</surname>
          </string-name>
          ,
          <string-name>
            <given-names>M.</given-names>
            <surname>Chi</surname>
          </string-name>
          ,
          <string-name>
            <given-names>T.</given-names>
            <surname>Barnes</surname>
          </string-name>
          , and
          <string-name>
            <given-names>T. W.</given-names>
            <surname>Price</surname>
          </string-name>
          .
          <article-title>Evaluating the e ectiveness of parsons problems for block-based programming</article-title>
          .
          <source>In Proceedings of the 2019 ACM Conference on International Computing</source>
        </mixed-citation>
      </ref>
    </ref-list>
  </back>
</article>