Academic Performance
Academic Performance
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10.1109/ACCESS.2020.3002791, IEEE Access
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ABSTRACT Digital data trails from disparate sources covering different aspects of student life are stored
daily in most modern university campuses. However, it remains challenging to (i) combine these data to
obtain a holistic view of a student, (ii) use these data to accurately predict academic performance, and (iii)
use such predictions to promote positive student engagement with the university. To initially alleviate this
problem, in this paper, a model named Augmented Education (AugmentED) is proposed. In our study, (1)
first, an experiment is conducted based on a real-world campus dataset of college students (N = 156) that
aggregates multisource behavioral data covering not only online and offline learning but also behaviors inside
and outside of the classroom. Specifically, to gain in-depth insight into the features leading to excellent or
poor performance, metrics measuring the linear and nonlinear behavioral changes (e.g., regularity and
stability) of campus lifestyles are estimated; furthermore, features representing dynamic changes in temporal
lifestyle patterns are extracted by the means of long short-term memory (LSTM). (2) Second, machine
learning-based classification algorithms are developed to predict academic performance. (3) Finally,
visualized feedback enabling students (especially at-risk students) to potentially optimize their interactions
with the university and achieve a study-life balance is designed. The experiments show that the AugmentED
model can predict students’ academic performance with high accuracy.
INDEX TERMS academic performance prediction, behavioral pattern, digital campus, machine learning (ML),
long short-term memory (LSTM)
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Author Name: Preparation of Papers for IEEE Access (February 2017)
be strongly correlated with academic performance. systems) are summarized in Table I. We first discuss the
Additionally, [32] showed that compared with high- and online prediction system, System A [32] (proposed by Z. Liu).
medium-achieving students, low-achieving students were less This system is relatively simple because its data is only
emotionally engaged throughout the semester and tended to captured from either SPOC or MOOC. Regarding the latter
express more confusions during the final stage of the semester. three offline prediction systems, i.e., Systems B ~ D [8,22,24]
By analyzing the effect of the factors influencing (proposed by R. Wang, Y. Cao, and Z. Wang respectively),
academic performance, many systems using data to predict the number of data sources is reduced, while the
academic performance have been developed in the literature corresponding scale size rapidly increases; Unfortunately, the
[1-4,7,8,13-19,22-27,29-31,33,34,37-41]. For instance, in number of different types of behaviors that could be
[8], academic performance was predicted based on passive considered is decreased. Ideally, multisource data at a
sensing data and self-reports from students’ smart phones. In medium/large scale could help lead to a better prediction
[23], a multitask predictive framework that captures system design. However, in practice, due to limitations, such
intersemester and intermajor correlations and integrates as computing capability, either data diversity or the sample
student similarity was built to predict students’ academic size is sacrificed during the system design process.
performance. In [34], based on homework submission data, TABLE I
FOUR TYPICAL PREDICTION SYSTEMS (PROPOSED BY PREVIOUS
the academic performance of students enrolled in a blended RESEARCHERS)
learning course was predicted.
Systems Scale Data Source Behaviors
According to their predicted academic performance, early Size (N)
feedbacks and interventions could be individually applied to System A
at-risk students. For example, in [33], to help students with (single- ⚫ online study
On-
source + 243 SPOC/MOOC ⚫ discussions on the
a low GPA, basic interventions are defined based on GPA line
medium forum
predictions. However, the research on the scale) [32]
feedback/intervention is still in the early stage, its ⚫ wearable sensors ⚫ activity
achievements are relatively few. smart phone ⚫ conversation
accelerometer ⚫ sleeping
In recent years, compared with primary and secondary System B
light sensor ⚫ location
(multisource
education (i.e. K12) [6,10,12,17], more and more attentions 30 microphone ⚫ socializing
+ small
have been paid to the academic performance prediction for GPS/Bluetooth ⚫ exercising
scale) [8]
⚫ self-reports ⚫ mental health
higher education [7-9,14,15,22-25,27,28,30-32,36-38]. The SurveyMonkey ⚫ stress
reasons contributing to this phenomenon warrant further mobile EMA ⚫ mood
investigation and might include the following. First, for ⚫ usage of smart card
Off- showering
college students on a modern campus, life involves a System C
line ⚫ WiFi eating
combination of studying, eating, exercising, socializing, etc. (almost
⚫ campus network consumption
multisource 528
(see Fig. 1) [7,8,22-25,27,42,43]. All activities that students ⚫ smart card ⚫ trajectory
+ medium
engage in (e.g., borrowing a book from the library) leave a ⚫ class schedule wake-up time…
scale) [24]
⚫ network
digital trail in some database. Therefore, it is relatively easy network cost…
to track college students’ behaviors, e.g. online learning System D ⚫ usage of smart card
behaviors captured from massive open online courses (single- showering
source + 18960 smart card eating
(MOOC) and small private online courses (SPOC) large scale) library entry-exit
platforms [30-32,36-38]. Second, given the diverse range [22] fetching water
of activities listed above, it could be difficult for college
students to maintain balanced, self-discipline, well-being To initially alleviate the challenges mentioned above, a
university experiences, including excellent academic model named Augmented Education (AugmentED) is
performance. proposed in this paper. As shown in Fig. 2, this model mainly
Although many academic performance prediction systems consists of the following three modules: (1) a Data Module in
have been developed for college students, the following which multisource data on campus covering a large variety of
challenges persist: (i) capturing a sufficiently rich profile of a data trails are aggregated and fused, and the
student and integrating these data to obtain a holistic view; (ii) characteristics/features that can represent students’ behavioral
exploring the factors affecting students’ academic change from three different perspectives are evaluated; (2) a
performance and using this information to develop a robust Prediction Module in which academic performance
prediction model with high accuracy; and (iii) taking prediction is considered a classification problem that is solved
advantage of the prediction model to deliver personalized by machine learning (ML)-based algorithms; and (3) a
services that potentially enable students to drive behavioral Feedback Module in which visualized feedback is delivered
change and optimize their study-life balance. individually based on the predictions made and feature
To address these challenges, four representative prediction analysis. Finally, AugmentED is examined using a real-world
systems (including one online system and three offline dataset of 156 college students.
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The remainder of this paper is organized as follows. In IV, the experimental results are discussed and analyzed.
Section II, a literature review is given. In Section III, the Finally, a brief conclusion is given in Section V.
methodology of AugmentED is described in detail. In Section
Meal Trajectory
Outside
Inside the Digital of the
Digital classroom Campus
classroom
Campus
Emotion
(a) (b)
FIGURE 1. Digital data remaining on a modern campus: (a) Multisource; (b) Multispace, covering not only online and offline learning but also students’
behaviors inside and outside of the classrooms.
➢Slope feature
➢Breakpoint selection
online smart learning emotion library Behavioral Change ➢RSS
learning card interaction -Linear visualized feedback
(BC-Linear)
➢Entropy
➢HMM-based intelligence
Entropy algorithm
meal consumption trajectory Behavioral Change ➢LyE
-nonLinear ➢HurstE
(BC-nonLinear) ➢DFA
➢LSTM-based
WiFi central clinic Behavioral Change features cross
storage visit -LSTM validation feature analysis
(BC-LSTM)
FIGURE 2. Overview of AugmentED. In the data module, the features blocked in dashed boxes (including LyE, HurstE, DFA, and LSTM-based features)
are proposed in our study, to the best of our knowledge, which is used for the first time in student’s behavioral analysis.
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during the first and second halves of the semester, statistical self-affinity or long-range dependence) of a
respectively. time series [56]. For example, in [56], DFA is used to
Second, the behavioral breakpoint can be captured by quantify the long-range correlation of a heart rate time
computing the rate of behavioral changes occurring across series, and it is demonstrated that a time series with a
the semester. The value of the breakpoint identifies the day small DFA value indicates less long-range correlation
during the semester before and after which a student’s behavior than a series with a large DFA value.
behavioral patterns differed. Two linear regressions can be Therefore, in heart rate analyses, DFA is considered a
used to fit a behavioral time series and then use the Bayesian long-range correlation indicator that can distinguish
information criterion (BIC) to select the best breakpoint [8]. healthy subjects from those with severe heart disease
If a single regression algorithm is selected, the breakpoint [56].
can be set to the last day. In summary, the above three nonlinear metrics can measure
2) BEHAVIORAL CHANGE-NONLINEAR (BC-NONLINEAR) the stability, predictability, and long-range correlation of a
In recent years, nonlinear metrics have been increasingly time series. Although these metrics have already been
applied to time series analysis [22,44-59]. extensively applied in time series analyses, e.g., gait time
Regarding the students’ behavioral time series, nonlinear series [47], in this study, for the first time, they are used in a
metrics have been used to discover nonlinear behavioral behavioral time series analysis. These metrics can enhance
patterns. We consider entropy an example. In [22], entropy our understanding of not only whether a student’s behavior
is proposed to quantify the regularity/orderliness of students’ is stable, predictable, and long-range correlated, but also how
behaviors, and it was demonstrated that a small entropy value good a student’s behavior is (e.g., self-discipline).
generally leads to high regularity and high academic 3) BEHAVIORAL CHANGE-LSTM (BC-LTSM)
performance. Another example is entropy calculated based Features represent temporal change over time is also worthy
on a Hidden Markov Model (HMM) analysis [44], which is of study. Such features can be extracted by long short-term
called HMM-based entropy for simplicity in our study. memory (LSTM) [58], which in this paper is called LSTM-
HMM-based entropy is proposed to quantify the based features for short. LSTM-based features have been
uncertainty/diversity of students’ behaviors, e.g., the applied in many fields, including for example emotion
uncertainty between the transition of different behaviors and recognition [59,60], traffic forecast [61] and video action
the various activities that a behavior exhibits. In [44], HMM- classification [62]. However, these features have not been
based entropy is evaluated by the following two steps: (i) applied in lifestyle behavioral analysis previously.
extracting the hidden states of a behavioral time series by
HMM [45,46]; and (ii) subsequently calculating the HMM- B. PREDICTION ALGORITHMS
based entropy of the extracted hidden states. In general, academic performance prediction can be
To further recognize students’ activities and discover their considered either a regression or a classification problem. A
nonlinear behavioral patterns, the following three new wide variety of algorithms have been used/proposed in
metrics, which have not been applied in students’ behavioral literatures to predict academic performance.
time series analysis previously, are also worth to be studied. For example, in [8], Lasso (least absolute shrinkage and
Lyapunov Exponent (LyE) [47-51] is a measure of the selection operator) regularized linear regression model,
stability of a time series. For example, in [47], LyE is proposed by Tibshirani [63] in 1996, is used to predict
used to quantify the stability of a gait time series, and academic performance. In [24], four supervised learning
the results demonstrate that a time series with a large algorithms (consisting of support vector machine (SVM),
LyE value is less stable than a series with a small LyE logistic regression (LR), decision tree and naï ve Bayes) are
value, i.e., generally, a large LyE value indicates high used to classify students’ performance. In [22], RankNET, a
instability. Therefore, in gait analyses, LyE is neural network method proposed by Burges et al. [64] in
considered a stability risk indicator for falls [47] that 2015, is used to predict the ranks of students’ semester
can distinguish healthy subjects from those at a high grades. Similarly, in [27], a layer-supervised MLP-based
risk of falling. method is proposed for academic performance prediction. In
Hurst Exponent (HurstE) [52-54] is a measure of [32], a temporal emotion-aspect model (TEAM), modeling
predictability (in some studies, it is also called long- time jointly with emotions and aspects extracted from SPOC
term memory) of a time series. For example, in [53], platform, is proposed to explore the effect of most concerned
HurstE is applied to quantify the predictability of a emotion-aspects as well as their evolutionary trends on
financial time series, and the results demonstrate that a academic achievement. In [65], four classification methods
time series with a large HurstE value can be predicted (consisting of Naï ve-Bayes, SMO, J48, and JRip) are used to
more accurately than a series with a HurstE value close predict students’ performance by considering student
to 0.5. heterogeneity.
Detrended Fluctuation Analysis (DFA) [54-57] is a In general, due to the lack of open-access, large-scale, and
measure of the long-range correlation (also called multisource data sets in the education field, on the one hand,
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to some extent, it is impossible to compare the performances following reasons: (1) more students were enrolled in this
of the existing academic performance prediction algorithms; course (N = 156) than other comparable courses, and (2) these
On the other hand, the algorithms proposed in this field are 156 students were more active on our self-developed SPOC
relatively simple, which are mainly based on basic statistics platform, thus providing abundant valuable behavioral data.
models (e.g. ANOVA and Post hoc tests) or ML algorithms Our dataset consists of the following four data sources (see
(e.g. SVM and LR). Table II):
⚫ SPOC Data. Two different types of data were collected
C. MULTISOURCE AND MULTIFEATURE on the SPOC platform. The first type is log files, which
It has been verified in many literatures that the predictive are recorded when a student logs in or out of the system,
power could be improved by multisource data and and the second type is posts on the SPOC discussion
multifeatured fusion. For example, it is demonstrated that forum, which records discussions related to students’
the performances of predicting both at-risk students [65] and learning experience.
stock market [66] could be improved by combining multi- ⚫ Smart Card Data. Similar to most modern universities,
source data. Similarly, in [22,23], the performances of in our university, all students have a campus smart card
academic performance prediction are improved by combing registered under their real name. The usage of this smart
traditional diligence features with orderliness (and sleep card, such as for borrowing books from the library,
patterns) features. In [67], the accuracy of scholars’ entering the library, consuming meals in campus
scientific impact prediction is improved by using multi-field cafeterias, shopping on campus, or making an
feature extraction and fusion. In [68], a contrast experiments appointment with the school clinic, is captured daily.
of eleven different feature combinations were conducted, ⚫ WiFi Data. There are approximately 3000 wireless
demonstrating that the performances of sentiment access points at our university, covering most areas of
classification can be improved by multifeatured fusion. campus. Once a student passes by one of these points,
However, we note that multisource and/or multifeature the MAC address of his/her device (e.g., tablet, laptop,
data cannot always guarantee a higher predictive power. For or smart phone) can be recorded [40]. In our study, to
instance, [69] shows that the results of predictive modeling, distinguish among diverse behaviors, the entire campus
notwithstanding the fact that they are collected within a is divided into several different areas, including a study
single institution, strongly vary across courses. Actually, area and a relaxation/dormitory area.
compared with single course, the portability of the prediction ⚫ Central Storage Data. As shown in Table II, other
models across courses (multisource data) is lower [69]. features used in our study, including the students’
Therefore, the effect of multisource and multifeature data personal information and academic records, are recorded
needs to be varied in experiments. by the central storage system of our university.
For simplicity, the former three data sources are designated D1,
III. Methodology D2, and D3, see Table II. To evaluate the effect of multisource
In our study, academic performance prediction is considered data on the academic performance prediction, which is similar
as a classification problem. According to the high-low to the studies introduced in Section II.C, contrast experiments
discrimination index proposed by Kelley [41], academic of different data source combinations were conducted in our
performance is divided into low-, medium-, and high- groups. study (see Section IV). To be specific, based on D1, D2, and
Given a digital campus dataset, according to Fig. 2, the main D3, in total, the following seven data combinations could be
task is to first extract features from the raw multisource data; obtained: D1, D2, D3, D1+D2, D1+D3, D2+D3, and D1+D2+D3.
then select the features that are strongly correlated with The latter data source, i.e., Central Storage (which is relatively
academic performance and use these features to train the static and simple), is considered fundamental information
classification algorithm; and finally provide visualized shared by all seven combinations.
feedback based on the prediction results. In our study, privacy protection is seriously considered, and
In this section, the three modules designed in AugmentED all students’ identifying information is anonymized. The
(see Fig. 2) are described in detail. infringement of students’ privacy is avoided during both the
data collection period and data analysis period. First, the
A. DATA MODULE student IDs are already pseudonymous in our raw data.
A flowchart of this module is shown in Fig. 3, which includes Moreover, the resolution of the students’ spatial-temporal
the following three parts. trajectory is reduced. All information regarding the exact
1) RAW DATA date/area showing when/where a behavior occurred is
Permission to access the raw data was granted by the removed. Therefore, it would be reasonably difficult to
Academic Affairs Office of our university. The raw dataset reidentify individuals through our dataset.
used in our study was captured from students engaging in the 2) DATA TRIALS
course of “Freshman Seminar” during the fall semester of In our study, to initially understand how a student’s behavior
2018-2019. The “Freshman Seminar” was chosen for the changes as the semester progresses, on the one hand, data
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Author Name: Preparation of Papers for IEEE Access (February 2017)
trails across the whole semester is processed and organized in slopes are calculated. Additionally, to further measure
chronological order, including when, where and how a the amount of variance in the dataset that is not
behavior occurs; On the other hand, data trails per week is explained by the traditional regression model, the
summarized according to preliminary statistics, including the residual sum of squares (RSS) is also evaluated (see
flowing information in each week, e.g., how often a behavior Table II). In our study, those linear metrics are mainly
occurs (i.e. total frequency), how long does a behavior last (i.e. calculated by the python model sklearn.linear_model.
duration), and how much money does a student need. ⚫ BC-nonLinear. Similar to the traditional approach,
Regarding the SPOC data (D1), online learning is first, entropy and HMM-based entropy are evaluated in
quantified by (i) learning frequency and duration, which are our study, measuring the regularity and diversity of
extracted from the raw log files; and (ii) online learning campus lifestyles respectively. Notably, the hidden
emotion, which is extracted from the discussion forum. states are numerically extracted by the MATLAB
Regarding the Smart Card data (D2), multiple behaviors are function hmmestimate, then the HMM-based entropy of
involved, e.g. library interaction (including borrowing a book the extracted hidden states is evaluated by the
and library entry), see Table II. Regarding the WiFi data (D3), MATLAB function entropy. Second, to further
first, student’s trajectory is calculated, mainly including when discover nonlinear behavioral patterns, the following
a student comes to a place; how often does he/she visit this three nonlinear metrics are proposed and extracted for
place (i.e. frequency); how long does he/she stay there (i.e. the first time: LyE, HurstE, and DFA, measuring the
duration). Second, attendance is calculated by combining stability, predictability, and long-range correlation of
WiFi data with class schedules. Specifically, to distinguish campus lifestyles respectively. In our study, four
among behavioral patterns during different periods, three nonlinear metrics (entropy, LyE, HurstE, and DFA) are
types of durations (namely, durations on working days, on evaluated by a numpy-based python library, i.e. nolds,
weekends, and throughout the semester) and two types of based on the 0&1 sequence (see Appendix A).
attendances (namely, attendance during the final study week ⚫ BC-LSTM. LSTM-based features representing
and attendance throughout the semester) are evaluated in our dynamic changes in temporal behavioral patterns are
study. calculated as follows. First, as input information, data
3) FEATURE EXTRACTION trails from multiple behaviors are organized together
To gain a deeper insight into students’ behavioral patterns, week by week, see Fig. 3. In each week, the basic
as summarized in Section II.A, in our study behavioral information of all multiple behaviors involved in our
change is evaluated by linear, nonlinear, and deep learning study is summarized, including for example how many
(LSTM) methods, see Fig. 3. times having breakfast and borrowing books from
⚫ BC-Linear. Similar to the traditional approach, linear library etc. occurred respectively. Subsequently, this
behavioral change is quantified by behavioral slope and weekly information is fitted into a Keras LSTM
behavioral breakpoint. Students behavioral series are network, then features representing the weekly
fitted by two linear regressions, subsequently the behavioral patterns that might change throughout
optimized breakpoint is selected by BIC and behavioral semester are extracted.
TABLE II
CHARACTERISTICS AND FEATURES EVALUATED IN OUR STUDY
Raw Data BC-Linear BC-nonLinear BC-LSTM Basic info.
(Behavioral Change-Linear) (Behavioral Change-nonLinear) (Behavioral
Change-LSTM)
Data Data Data Content Slope Breakpoint RSS Entropy HMM-based LyE HurstE DFA LSTM-based Freq Duration
Source Label Entropy Features
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Author Name: Preparation of Papers for IEEE Access (February 2017)
Feature Extraction
data trials per week Behavioral Change-Linear (BC-Linear)
Linear regressions + ➢Slope
Bayesian information ➢Breakpoint
Statistical Results
Statistical Results
Statistical Results
criterion (BIC) ➢RSS
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similar, which can all lead to a good prediction result. To SVM* 0.807 0.843 0.807 0.799 0.843
XGBoost* 0.807 0.843 0.807 0.803 0.867
clarify, we consider the case of precision values, see the 5th
RF 0.584 0.612 0.584 0.567 0.662
column of Table III. The precision values of five ML GBRT 0.571 0.584 0.571 0.560 0.626
algorithms are 0.873, 0.877, 0.863, 0.889, and 0.871 C-I KNN 0.551 0.593 0.551 0.558 0.641
respectively, indicating that (i) its minimum value is 0.863, i.e. D2+D3 SVM 0.545 0.550 0.545 0.530 0.579
the precision of AugmentED is no less than 86.3%; (ii) the XGBoost 0.559 0.563 0.559 0.544 0.579
(Smart C-II LSTM 0.449 0.469 0.449 0.434 0.551
difference between the minimum and maximum values is Card + RF* 0.781 0.819 0.781 0.782 0.837
0.026, which is quite small, i.e. AugmentED is independent of WiFi) GBRT* 0.781 0.801 0.781 0.779 0.816
ML algorithms. C-III KNN* 0.755 0.793 0.755 0.754 0.793
TABLE III SVM* 0.762 0.794 0.762 0.763 0.815
PREDICTION RESULTS (THE AVERAGE CLASSIFICATION RESULTS OF 10- XGBoost* 0.762 0.801 0.762 0.767 0.813
FOLDER CROSS VALIDATION) RF 0.630 0.679 0.630 0.630 0.699
Data Feature Algorithm accuracy precision recall f1 AUC GBRT 0.637 0.671 0.637 0.620 0.703
RF 0.604 0.642 0.604 0.602 0.698 D1+D2+ C-I KNN 0.604 0.647 0.604 0.596 0.669
GBRT 0.584 0.643 0.584 0.581 0.684 D3 SVM 0.635 0.696 0.635 0.644 0.716
C-I KNN 0.500 0.497 0.500 0.473 0.627 XGBoost 0.608 0.670 0.608 0.598 0.691
SVM 0.539 0.590 0.539 0.534 0.641 (SPOC + C-II LSTM 0.501 0.544 0.501 0.473 0.578
D1 XGBoost 0.521 0.586 0.521 0.520 0.605 Smart RF* 0.852 0.873 0.852 0.844 0.857
C-II LSTM 0.488 0.517 0.488 0.491 0.583 Card + GBRT* 0.852 0.877 0.852 0.852 0.876
(SPOC) RF* 0.776 0.806 0.776 0.774 0.807 WiFi) C-III KNN* 0.847 0.863 0.847 0.841 0.851
GBRT * 0.764 0.784 0.764 0.761 0.800 SVM* 0.866 0.889 0.866 0.865 0.872
C-III KNN* 0.801 0.825 0.801 0.802 0.840 XGBoost* 0.859 0.871 0.859 0.850 0.874
SVM* 0.795 0.818 0.795 0.792 0.836
Note: (i) D1+D2+D3 is the multiple data source used in AugmentED to predict
XGBoost* 0.789 0.823 0.789 0.787 0.836
academic performance, including SPOC, Smart Card and WiFi data; (ii) The
RF 0.507 0.538 0.507 0.496 0.600
rows highlighted in light blue, light pink, light green, denote the three
GBRT 0.487 0.510 0.487 0.481 0.604 following feature or feature combinations are used for prediction, C-I (BC-
C-I KNN 0.462 0.523 0.462 0.454 0.617 linear and BC-nonlinear features), C-II (only BC-LSTM, i.e., LSTM-based
SVM 0.528 0.571 0.528 0.515 0.637 features), C-III (BC-Linear, BC-nonLinear, and BC-LSTM features).
D2 XGBoost 0.508 0.522 0.508 0.495 0.617
C-II LSTM 0.436 0.467 0.436 0.425 0.552
(Smart B. COMPARATIVE EXPERIMENTS
RF* 0.742 0.795 0.742 0.746 0.808
Card)
GBRT* 0.737 0.778 0.737 0.733 0.791 In this part, contrast experiments are conducted to evaluate the
C-III KNN* 0.733 0.780 0.730 0.729 0.771 prediction effect of multisource and multifeature
SVM* 0.719 0.744 0.719 0.712 0.773 combinations.
XGBoost* 0.733 0.760 0.733 0.733 0.767
RF 0.424 0.408 0.424 0.395 0.511 1) MULTISOURCE
GBRT 0.437 0.473 0.437 0.428 0.532 Comparisons of the performance of different data source
C-I KNN 0.399 0.424 0.399 0.396 0.531 combinations are conducted, see the 1st column of Table III.
SVM 0.391 0.432 0.391 0.387 0.480
XGBoost 0.425 0.383 0.425 0.395 0.503
As shown in Table III, a large number of multiple data sources
D3
C-II LSTM 0.413 0.398 0.413 0.380 0.512 can lead to a more accurate prediction result.
(WiFi) RF* 0.545 0.620 0.545 0.539 0.639 To clarify, we consider the case of SVM*, from D1 to D1+D2
GBRT* 0.558 0.600 0.558 0.548 0.650 and D1+D2+D3 (see Tables III and Fig. 4), all five evaluation
C-III KNN* 0.501 0.591 0.501 0.487 0.607
indexes significantly improves with the types of data sources
SVM* 0.487 0.404 0.487 0.416 0.590
XGBoost* 0.546 0.624 0.546 0.529 0.646 increases. Specifically, (i) the accuracy values of D1, D1+D2,
RF 0.616 0.660 0.616 0.608 0.688 and D1+D2+D3 are 0.795, 0.821, 0.866, respectively; (ii) the
GBRT 0.603 0.676 0.603 0.605 0.692 precision values are 0.818, 0.848 and 0.889; (iii) the recall
C-I KNN 0.534 0.608 0.534 0.526 0.626
values are 0.795, 0.821 and 0.866; (iv) the f1 values are 0.792,
D1+D2 SVM 0.608 0.661 0.608 0.617 0.683
XGBoost 0.565 0.603 0.565 0.556 0.641 0.821 and 0.865; and (v) the AUCs value are 0.836, 0.862 and
(SPOC + C-II LSTM 0.493 0.520 0.493 0.488 0.579 0.872. It is verified that multisource data can enhance the in-
Smart RF* 0.814 0.839 0.814 0.815 0.855 depth insight gained into students’ behavioral patterns.
Card) GBRT* 0.809 0.843 0.809 0.809 0.853
C-III KNN* 0.815 0.839 0.815 0.815 0.857
SVM* 0.821 0.848 0.821 0.821 0.862
XGBoost* 0.833 0.860 0.833 0.826 0.813
RF 0.616 0.650 0.616 0.614 0.697
GBRT 0.616 0.664 0.616 0.612 0.702
C-I KNN 0.538 0.594 0.538 0.529 0.626
D1+D3 SVM 0.602 0.640 0.602 0.598 0.690
XGBoost 0.573 0.606 0.573 0.568 0.626
(SPOC +
C-II LSTM 0.488 0.500 0.488 0.469 0.559
WiFi)
RF* 0.800 0.867 0.800 0.799 0.849
C-III GBRT* 0.793 0.851 0.793 0.795 0.851
KNN* 0.814 0.859 0.814 0.811 0.857
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Author Name: Preparation of Papers for IEEE Access (February 2017)
D1+D2+D3
To illuminate how AugmentED could potentially help
D2+D3
D1+D3
D1+D2
students optimize their college lifestyles and consequently
improve their academic performance, a feedback example
0.4
D3
D2
D1
LSTM
LSTM
LSTM
LSTM
GBRT
KNN*
SVM*
SVM
KNN
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From this perspective, in Fig. 6, nine assistant indicators are depth insight into student behavioral patterns and potentially
calculated and plotted. help students to optimize their interactions with the university.
We begin by discussing the indicators of -linear, -nonlinear, In our study, a model named AugmentED is proposed to
and -LSTM features (see Appendix B), which are denoted as predict the academic performance of college students. Our
D-linear, D-nonLinear and D-LSTM respectively, contributions in this study are related to three sources. First,
representing the (weighted) linear, nonlinear and temporal regarding data fusion, to the best of our knowledge, this work
pattern of all multiple behaviors involved in our study (rather is the first to capture, analyze and use multisource data
than one single behavior). Regarding these three indicators, covering not only online and offline learning but also campus-
(i) The average values and 95% confidence intervals life behaviors inside and outside of the classroom for academic
(from the low-, medium-, and high- academic performance prediction. Based on these multisource data, a
performance groups) are plotted in the left column of rich profile of a student is obtained. Second, regarding the
Fig. 6. feature evaluation, behavioral change is evaluated by linear,
(ii) The Pearson correlation between the indicators and nonlinear, and deep learning (LSTM) methods respectively,
academic performance is calculated, see the 2nd, 5th, which provides a systematical view of students’ behavioral
and 8th rows of Table IV which are highlighted in light patterns. Specifically, it is the first time that three novel
gray. nonlinear metrics (LyE, HurstE, and DFA) and LSTM are
Furthermore, six more indicators are calculated and applied in students’ behavioral time series analysis. Third, our
provided as supplementary, see the 2nd and 3rd columns of Fig. experimental results demonstrate that AugmentED can predict
6. The Pearson correlation between these indicators and academic performance with quite high accuracy, which help
academic performance is also calculated and listed in Table IV. to formulate personalized feedback for at-risk (or unself-
From Table IV it can be seen that all the nine indicators are disciplined) students.
strongly correlated with academic performance. Additionally, However, there are also some limitations in our study. To
in Fig. 6, the apparent distinction among three academic gain a multisource dataset, we scarified the scale the dataset
performance groups demonstrates that all the nine indicators by only using student-generated data within a single course.
can offer strong support in at-risk student identification. This limitation might have a certain negative influence on the
To clarify, we consider the case of D-linear. On the one generalization of AugmentED. Furthermore, in this study, we
hand, its average values and 95% confidence intervals from mainly focus on behavioral change. Other
low-, medium-, and high- academic performance groups are characteristics/features (e.g., peer effect, sleep) that are worthy
(1.4570.199, 2.1600.193, 3.0350.341), see Fig. 6(a1), of consideration were not evaluated in this study.
indicating clear separation. On the other hand, its correlation In conclusion, our study is based on a complete passive
coefficient is 0.534, see the 3rd row of Table IV, i.e., this daily data capture system that exists in most modern
indicator is significantly correlated with academic universities. This system can potentially lead to continual
performance. Therefore, D-linear can be taken as an indicator investigations on a larger scale. The knowledge obtained in
to explore which student is at risk because of the low this study can also potentially contribute to related research
performance he/she will achieve. among K-12 students.
TABLE IV
CORRELATION COEFFICIENT AND P-VALUE Appendix A
Assistant Indexes Correlation coefficient P-value
Fig.6(a1) D-Linear 0.534 7.18e-13 To evaluate the four nonlinear metrics (entropy, LyE, HurstE,
Fig.6(a2) D-postRSS 0.366 2.65e-06 and DFA) of the time series, we concentrate on the precise
Fig.6(a3) D-preSlope 0.425 3.12e-08 time of day during which the behaviors occurred. Therefore,
Fig.6(b1) D-nonLinear 0.392 4.28e-07 in our study, the involved time is first converted to a discrete
Fig.6(b2) D-entropy 0.402 2.02e-07
Fig.6(b3) D-DFA 0.345 1.05e-05
time sequence. Then, according to the represented discrete
Fig.6(c1) D-LSTM 0.703 1.32e-24 time sequence, the raw behavioral time series data are
Fig.6(c2) LSTM-49 0.254 0.001 converted to the 0&1 sequence as follows:
Fig.6(c3) LSTM-1 0.734 1.23e-27
STEP 1. TIME DATA REPRESENTATION
V. CONCLUSION AND FUTURE WORK The time data are converted to a discrete sequence with a
As an important issue in the education data mining field, normalized time interval by the following three steps:
academic performance prediction has been studied by many ⚫ Step 1.1. The entire semester was from 01/09/2018
researchers. However, due to lack of richness and diversity in (September 1st) to 20/01/2019 (January 20st) and includes
both data sources and features, there still exist a lot of a total of 140 days. Thus, each day can be numbered
challenges in prediction accuracy and interpretability. To from 1 to 140, resulting in a discrete sequence {p1, p2, . . .,
initially alleviate this problem, our study aims at developing a pi} = {1, 2, . . ., 140}, where i denotes the ith day in the
robust academic performance prediction model, to gain an in- semester;
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Author Name: Preparation of Papers for IEEE Access (February 2017)
⚫ Step 1.2. We divide each day into 48 time bins such that ( N − Rank ( xn )) / N , Corr ( X k ) 0 (B-1)
each bin spans 30 minutes. Subsequently, every bin is Scorekn =
Rank ( xn ) / N , Corr ( X k ) 0
encoded from 1 to 48, i.e., {q1, q2, . . ., qj} = {1, 2, . . .,
48}, where j denotes the jth time bin. For example, We assume that there are N students and K extracted
“0:01—0:30” is the 1st time bin, “0:31—1:00” is the 2nd features in total. Corr(Xk) is the Pearson correlation
bin, etc. coefficient between the kth feature XK and students’
⚫ Step 1.3. By combining the sequences of days and time academic performance, where k K. Rank(xn) means the
bins, the time during the spring semester is mapped to a ranking of the nth student’s (denoted as un, where n N)
discrete time sequence with length Nt, i.e., {T1, T2, . . ., feature among all students. For example, there are three
Tij} = {1, 2, . . ., Nt}, where students (u1, u2, u3), and their kth feature (e.g. slope value
Tij =( pi − 1) 48 + q j , (A-1) of having breakfast) are (0.8, 0.4, 0.6), then we have
And Nt = 6720. Specifically, if the time is “03/09/2018, Scorek1 = 0, Scorek2 = 0.667, and Scorek3 = 0.333 because
10:24”, i.e., pi = 3 and qj = 21 (the 21st time bin of the 3rd Corr(Xk) > 0.
day), according to Eq. A-1, Tij = 2 48 + 21 = 117, i.e., ⚫ Step 2. The indicator of linear feature group, D-Linear,
“03/09/2018, 10:24” is encoded by 117. is calculated by utilizing the feature scores as follows,
K
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