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  <front>
    <journal-meta />
    <article-meta>
      <title-group>
        <article-title>Exploring Gritty Students' Behavior in an Intelligent Tutoring System</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>Erik Erickson</string-name>
          <email>eerickson@wpi.edu</email>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Ivon Arroyo</string-name>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Beverly Woolf</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <aff id="aff0">
          <label>0</label>
          <institution>University of Massachusetts Amherst</institution>
          ,
          <addr-line>Amherst MA, 01003</addr-line>
          ,
          <country country="US">USA</country>
        </aff>
        <aff id="aff1">
          <label>1</label>
          <institution>Worcester Polytechnic Institute</institution>
          ,
          <addr-line>Worcester MA 01609</addr-line>
          ,
          <country country="US">USA</country>
        </aff>
      </contrib-group>
      <fpage>121</fpage>
      <lpage>126</lpage>
      <abstract>
        <p>This research focuses on determining whether a student's GRIT impacts their behavior within an intelligent tutoring system, towards developing better student models and feature sets that can help a tutor predict student behavior and determining whether computer tutors might foster improvements in students' grit, perseverance and recovery from failure. We use rare Association Rule Mining to explore how students' grit may be associated with students' behaviors within MathSpring, an intelligent tutoring system, as a first step.</p>
      </abstract>
      <kwd-group>
        <kwd>Grit</kwd>
        <kwd>Perseverance</kwd>
        <kwd>Student Models</kwd>
        <kwd>Association Rule Mining</kwd>
      </kwd-group>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>Introduction</title>
      <p>
        Studies have shown that grit is more predictive of life’s outcomes compared to the
“Big Five” personality model, which is a group of broad personality dimensions (e.g.
conscientiousness, extraversion, agreeableness, and neuroticism [
        <xref ref-type="bibr" rid="ref15">15</xref>
        ]), but unlike IQ,
the previous gold-standard predictor for life outcomes, grit may not be a static quality
but one that can be developed [
        <xref ref-type="bibr" rid="ref12">12</xref>
        ]. Grit has become ubiquitous in the lexicon of public
schools across America [
        <xref ref-type="bibr" rid="ref20">20</xref>
        ]. Educators are looking for answers to some lingering
questions: “Can students increase their grittiness?” and “How do students go about doing
so?”. Gritty individuals can maintain high determination and motivation for a long time
despite battling with ‘failure and adversity’. Students can increase their grittiness
through classroom activities [
        <xref ref-type="bibr" rid="ref20">20</xref>
        ]. Educators are interested in fostering growth in
children, and would be interested in fostering grit in their students.
      </p>
      <p>Our research focuses on how a student’s grit and perseverance might impact
behavioral patterns in a tutoring system, towards understanding how digital tutors might
foster gritty-like behaviors, and in turn, grit assessments.</p>
      <p>We move research on grit forward as a tool to refine student models in intelligent
tutoring systems, by answering the following questions:</p>
      <sec id="sec-1-1">
        <title>RQ#1. Can we predict if a student is gritty or not by looking his/her behaviors? Here, grit is a target to predict, or a consequence.</title>
      </sec>
      <sec id="sec-1-2">
        <title>RQ#2. Does the grit of a student influence student behavior inside a tutor? In which way(s)? Here grit is a cause or antecedent</title>
      </sec>
    </sec>
    <sec id="sec-2">
      <title>Method</title>
      <p>
        Grit has typically been assessed using Duckworth’s instrument of the Grit Scale [
        <xref ref-type="bibr" rid="ref13">13</xref>
        ],
asking students to report on twelve Likert-scale questions. Some examples of questions
are, “I often set a goal but later choose to pursue a different one” and “Setbacks don’t
discourage me.”
      </p>
      <p>
        Our testbed is MathSpring, an intelligent tutoring system (ITS) that personalizes
problems by assessing students’ knowledge as well as effort and affect as they engage
in mathematics practice online [
        <xref ref-type="bibr" rid="ref5 ref6 ref7">5-7</xref>
        ]. Students used MathSpring during class time over
several days, as part of their regular mathematics class, and solved many math
problems, while the system captured detailed event-level and problem-level information on
their performance. These students also filled out a grit scale survey [
        <xref ref-type="bibr" rid="ref8">8</xref>
        ] that produced in
an aggregate grit score.
2.1
      </p>
      <sec id="sec-2-1">
        <title>Data Collection and Data Mining</title>
        <p>Seventh grade students from two school districts participated in a research study. After
combining the two datasets, there were 456 rows of Grit survey responses representing
thirty-eight students. Sixty-eight students used MathSpring, producing 3,012 rows of
data, each representing a student-math problem interaction. Variables were discretized
into Booleans, indicating high/low or true/false. We created the negation of each
variable (e.g., for GUESS, we also created a counterpart NoGUESS variable with the
opposite truth value) to be considered also. Along with Guess, other variables included
Hi/Low Grit, is/is not Solved, Hi/Low Mistakes, Hi/Low Hints, Yes/No Finished,
Not/Likely Read (the problem).</p>
        <p>We used Association Rule Mining to discover rules, a non-parametric method
for exploratory data analysis, which finds associations that occur more frequently than
expected from random sampling. The four critical parameters and minimum thresholds
used are the following: Support 0.05, Confidence 0.84, Lift 1.15, Conviction 1.75. Last,
we subjected the most important rules to a Chi-Square statistical test, those with solely
“High Grit” or “Low Grit” as a consequent or antecedent.
3</p>
      </sec>
    </sec>
    <sec id="sec-3">
      <title>Results</title>
      <p>
        The mean Grit Score for the N=38 students in the sample was M=3.07, SD=0.51,
Median=3, Range= [
        <xref ref-type="bibr" rid="ref1 ref5">1,5</xref>
        ]. This means the student grit assessment had some variability but
the distribution is centered on a neutral grit value. A median split was done, classifying
students as low or high grit, so that half of the students were considered gritty or not.
Interestingly, we found that High-Grit students had much more activity, 71% of the
student-problem interactions in the dataset vs. 29% for the non-gritty students. Table 4
shows the number and percent of cases for notable variable in detail, after the
discretization process.
      </p>
      <p>Due to a low support threshold of 0.05, thousands of rules were created. Only a
selected subset of rules was chosen for interpretation, mainly those rules with a single
consequent or antecedent, and those which met thresholds and had highest values for
the metrics of confidence, conviction and lift.</p>
      <p>A notable finding was that no rules with LowGrit as a consequent appeared at all
according to our criteria specified in the parameter thresholds. This made us realize
that, due to the much lower number of math problems seen by Low Grit students, the
confidence for any rule with LowGrit=1 as a consequent would be at chance level at
0.288 (as opposed to 0.5). We realized how the confidence metric is not very reliable
in this case due to the imbalanced dataset. On the other hand, the metric that balances
the rarity of the premises of a rule and their confidence is the ‘conviction’ parameter.
We thus set conviction as our first priority for selection of rules.</p>
      <p>Table 5 shows the rules that had the highest conviction, confidence and lift. These
rules also are the most complete rules (as generally subsequent rules that met the
parameter thresholds had similar premises, but combined subsets of the propositions).
Rule A is the rule with highest confidence, conviction and lift, and states that if a
student made a high amount of mistakes in a math problem, and asked for many hints as
a way to help them solve the problem, then it means the student has a high level of Grit.
This joint condition happened in 19% of the total student-problem interactions
examined. The significance of the effect for each rule was verified with a Chi-Square test by
computing cross-tabulations between the premise being true/false vs. High/Low Grit
(p&lt;0.0001 for rules 1, 2, and 3).</p>
      <p>On the other hand, no rules were found that met the thresholds of confidence, lift
and conviction for LowGrit as a consequent. Still, we show the rule that has the best
outcome for those metrics. The implication LowMistakes ^ isSolved → Low Grit has a
confidence level of 0.45, which is low, however, it is higher than chance as stated earlier
(chance level for any LowGrit row is 0.288). The rule suggests that if a student solves
problems by making a low number of mistakes, then the student is NOT gritty.</p>
      <p>Table 6 summarizes the found rules with Low/High Grit as a premise. This time, it
was easier to find rules with LowGrit as an antecedent that met the thresholds of
confidence, lift and conviction but not for HiGrit. Rule C is the main rule found for Low Grit
as an antecedent (other similar rules are variations of this same effect), suggesting that
if a student has low grit, then they will likely ask for few hints in a problem.</p>
      <p>
        The rule that contains HiGrit as an antecedent is Rule D. While Rule D does not
meet the lift and conviction thresholds we had set, it does meet the confidence
threshold, and is the rule found with the highest values of confidence and conviction. This
rule captures that if a student is gritty, then the student will not quick-guess the correct
answer to a problem. Remember that guessing implies that a student entered many
answers incorrectly and did not ask for help/hints, until they manage to solve it correctly
(the multiple-choice format in most questions in MathSpring probably favors this type
of disengagement behavior in general). We consider that students who guess are
avoiding help when they should instead be asking for it, as they are answering incorrectly, as
stated in previous research [
        <xref ref-type="bibr" rid="ref1 ref2">1,2</xref>
        ]. Rushing to get the right answer without fully
understanding why, and avoiding seeking help.
This research starts unpacking how grit may be expressed in student behaviors inside
an intelligent tutor, and on learning how fostering gritty-like behaviors might eventually
improve a students’ grit. In general, the results of Association Rule Mining suggest that
there are differences students' behaviors depending on their assessed level of grit.
Apparently, students who are gritty tend to neither quick-guess answers to problems, nor
making lots of mistakes while avoiding help. At the same time, rules found with grit as
a consequent suggest that if a student is in a situation of conflict, making mistakes but
resolving them by asking for hints (or videos or examples), we can predict that the
student has high grit. This is a desirable behavior when facing challenge in interactive
learning environments, as specified by a review on help seeking and help provision in
interactive learning environments [
        <xref ref-type="bibr" rid="ref2">2</xref>
        ].
      </p>
      <p>It was harder to find Association Rules that associate students with low grit with
behaviors (there are not as many systematic behavior patterns that could be associated
to students of low grit). Still, the few rules found suggest that when a student has low
levels of grit, they will seek for a low amount of hints. Conversely, the behavior that a
student is NOT gritty is that he/she makes a low number of mistakes and eventually
solves the problems correctly. Given the agency that MathSpring allows (more than
most other learning environments) this does not necessarily mean that low-grit students
tend to solve problems correctly (otherwise solve-on-first would have been part of the
rules found). Students who skip problems or give-up will receive easier problems in an
adaptive tutor. Also, students could choose material that is easier, or already mastered,
to guarantee higher levels of success. Further analyses could help discern if this is the
case, by analyzing the level of difficulty of the problems students received. Grit is a
construct that will predetermine students to have different kinds of self-regulatory
behaviors while learning in interactive learning environments.</p>
      <sec id="sec-3-1">
        <title>Acknowledgements</title>
        <p>This material is based upon work supported by the National Science Foundation under NSF
award #1551594 INT: Collaborative Research: Detecting, Predicting and Remediating Student
Affect and Grit Using Computer Vision. Any opinions, findings, and conclusions or
recommendations expressed in this material are those of the author(s) and do not necessarily reflect the
views of the National Science Foundation.</p>
      </sec>
    </sec>
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