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  <front>
    <journal-meta />
    <article-meta>
      <title-group>
        <article-title>Does Time Matter in Analyzing Educational Data? - A New Dataset for Streaming Learning Analytics</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>Gabriella Casalino</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Giovanna Castellano</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Gianluca Zaza</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <aff id="aff0">
          <label>0</label>
          <institution>Computer Science Department, University of Bari Aldo Moro Bari</institution>
          ,
          <country country="IT">Italy</country>
        </aff>
      </contrib-group>
      <abstract>
        <p>This research introduces a novel dataset developed for streaming learning analytics, derived from the Open University Learning Analytics Dataset (OULAD). The dataset incorporates essential temporal information that captures the timing of student interactions with the Virtual Learning Environment (VLE). By integrating these time-based interactions, the dataset enhances the capabilities of stream algorithms, which are particularly well-suited for real-time monitoring and analysis of student learning behaviors. Experiments utilizing the Online Bagging algorithm across three temporal units-months, trimesters, and semesters-demonstrated that the dataset contains pertinent information for predicting student outcomes. Despite the variations associated with diferent temporal units, the classifier efectively identified patterns within the data, especially for the majority class (Pass), achieving high F1 scores. These results indicate that the temporal structure of the data supports accurate predictions; however, challenges remain in accurately identifying the minority class (Fail). This dataset paves the way for more dynamic and responsive educational interventions by enabling timely predictions of student outcomes. Such capabilities facilitate continuous learning support within VLEs, allowing educators to respond promptly to student needs and enhance overall learning experiences.</p>
      </abstract>
      <kwd-group>
        <kwd>eol&gt;Learning Analytics</kwd>
        <kwd>Dataset</kwd>
        <kwd>Education</kwd>
        <kwd>Machine Learning</kwd>
        <kwd>Stream Data Mining</kwd>
      </kwd-group>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>1. Introduction</title>
      <p>course design. Furthermore, academic institutions can establish tailored support measures based
on the analysis.</p>
      <p>
        Nevertheless, the majority of existing literature tends to treat educational data as a static
entity, failing to account for the inherently dynamic nature of the learning process [
        <xref ref-type="bibr" rid="ref4 ref5 ref6">4, 5, 6, 7, 8</xref>
        ].
An exception to this trend is found in studies focused on knowledge tracing, a machine-learning
methodology that models and predicts the evolution of an individual student’s learning trajectory
over time through the analysis of their interactions with educational content. This approach
utilizes temporal information to monitor the progression of a student’s knowledge, thereby
allowing for more accurate predictions of future performance based on historical learning
behaviors [9, 10].
      </p>
      <p>However, only a limited number of studies have integrated temporal factors into their
analyses, apart from those concerning knowledge tracing. For instance, it has been observed in
[11] that traditional machine-learning methodologies often overlook the dynamic nature of
educational interactions, which could be more efectively analyzed through data stream
methodologies. Stream algorithms are specifically designed to process continuous data in real time,
eficiently managing large or continuous data streams with constrained memory and
computational resources [12]. This capability renders them particularly suitable for analyzing student
interactions with VLEs, given the substantial and ongoing data generated by student activities.
The same authors also introduced explainable stream algorithms to facilitate the processing
and interpretation of educational data, taking into account the temporal evolution of student
interactions for more insightful analyses [13, 14]. Nevertheless, a significant obstacle impeding
the progress of learning analytics for evolving data remains the scarcity of time-stamped data.</p>
      <p>In this study, we utilized the information contained in the well-established Open University
Learning Analytics Dataset (OULAD) [15] to create a student-oriented dataset that preserves the
temporal evolution of user interactions, in conjunction with other demographic and evaluative
information. Our dataset comprises 1 718 984 entries, with each instance characterized by 34
features that delineate the number of student interactions with each VLE facility (e.g., forum,
glossary, homepage, HTML activity, etc.), alongside demographic data and the student’s grade,
for a specific student, course, and time  . The target classes are classified as follows: Withdraw,
Fail, Pass, and Distinction.</p>
      <p>We employed a stream classification algorithm, specifically Online Bagging, applied to
data partitioned into smaller subsets based on temporal units such as months, trimesters,
and semesters. This approach was designed to ascertain whether the resultant data provides
suficient information to predict students’ outcomes over time.</p>
      <p>The primary research question we seek to address is: “ (Does time influence the efectiveness of
classification models in predicting students’ outcomes?” To explore this question, we examined
various temporal periods, commencing with six months, followed by three months, and finally
one month. We utilized the Online Bagging stream classification algorithm to investigate: i)
whether the information within these temporal frames is adequate for accurate predictions; ii)
whether there are performance diferences based on the chosen periods; and iii) whether the
stream classifier can efectively learn from small, incremental data subsets.</p>
      <p>The structure of the manuscript is organized as follows: Section 2 delineates the methodology
employed to extract temporal information from the OULAD dataset, along with a comprehensive
description of the newly constructed data and relevant statistics. Section 3 elaborates on the
experimental procedures involving the stream algorithm, demonstrating how to process the
new data and assess classification performance. Finally, Section 4 summarizes our conclusions
and outlines potential avenues for future research.</p>
    </sec>
    <sec id="sec-2">
      <title>2. Data</title>
      <p>One significant limitation associated with the application of stream algorithms within the
educational context is the scarcity of data containing temporal information. To address this
challenge, we manipulated the Open University Learning Analytics Dataset (OULAD) [15] to
incorporate time-based data, thereby enabling us to leverage the timing of student interactions.
However, it is important to note that the anonymization process employed in the original
OULAD dataset means that the temporal information is not absolute; rather, it is relative to the
start date of each module, which remains undisclosed.</p>
      <p>The primary files utilized from the OULAD dataset in this study include:
• courses.csv: Contains information regarding course modules and their presentations,
including columns such as ‘code_module‘, ‘code_presentation‘, and ‘length‘.
• assessment.csv : Details the assessments corresponding to each module presentation, with
columns including ‘code_module‘, ‘code_presentation‘, ‘id_assessment‘, ‘assessment_type‘,
‘date‘, and ‘weight‘.
• vle.csv : Provides information on the materials available within the VLE, featuring columns
such as ‘id_site‘, ‘code_module‘, ‘code_presentation‘, and ‘activity_type‘.
• studentInfo.csv : Contains demographic data and student results, encompassing columns
such as ‘code_module‘, ‘code_presentation‘, ‘id_student‘, ‘gender‘, ‘region‘,
‘highest_education‘, ‘imd_band‘, ‘age_band‘, ‘num_of_prev_attempts‘, ‘studied_credits‘,
‘disability‘, and ‘final_result‘.
• studentRegistration.csv : Details student registrations for modules,
including ‘code_module‘, ‘code_presentation‘, ‘id_student‘, ‘date_registration‘, and
‘date_unregistration‘.
• studentAssessment.csv : Records student assessment results, with columns such as
‘id_assessment‘, ‘id_student‘, ‘date_submitted‘, ‘is_banked‘, and ‘score‘.
• studentVle.csv : Captures student interactions with VLE materials, featuring
‘code_module‘, ‘code_presentation‘, ‘id_student‘, ‘id_site‘, ‘date‘, and ‘sum_click‘.</p>
      <p>To construct a comprehensive dataset, we initially merged data from various CSV files to
consolidate information pertaining to modules and presentations.</p>
      <p>In detail, the initial step involved merging the student_info and student_vle tables based on
the features code_module , code_presentation , and id_student , resulting in a consolidated table
that integrated information from both sources. Subsequently, this consolidated table was merged
with the vle table, utilizing code_module , code_presentation , and id_site as reference points to
create a table containing information on activity types. The assessments and student_assessment
tables were merged using the id_assessment feature. Finally, the two resulting tables were
joined using the id_student and date features, thereby creating a comprehensive dataset that
encapsulates relevant student interactions and assessment results.</p>
      <p>We then analyzed student interactions with VLE materials to identify usage patterns and
assess engagement levels. Additionally, we integrated assessment results with interaction
dates to examine the correlation between student interactions and performance outcomes. The
dataset underwent a thorough cleaning and transformation process to address missing values
and normalize the data, ensuring consistency and reliability in our analysis.</p>
      <p>Upon consolidating the data into a unified table, which includes student information and
their interactions for a specific student , course , module  , and a given time  (measured
in days from the start date of each module), we sought to transform this temporal information.
The original dataset recorded a minimum temporal granularity of one day, thus precluding
the extraction of day partitions. Given that the dataset provides only relative time values,
our objective was to convert these into a linear and incremental format spanning the years
represented in the OULAD data. This transformation allows us to maintain the relative nature of
the time while ensuring usability for analysis and efectively reflecting the temporal progression
of student interactions throughout their studies.</p>
      <p>Modules in the original OULAD data can commence in February (denoted by the letter B) or
October (denoted by the letter J). To ensure consistency and establish a progressive timeline
from a single reference date, we transformed these dates into a count of incremental days,
commencing from the first module in February (B). The transformation process involved the
following steps:
1. Identification of the Base Date : We established the start date for the 2013B presentation
as the reference point (zero).
2. Calculation of the Efective Date : We converted the relative dates of the other
presentations into days elapsed since the identified start date, taking into account the number of
days between the various modules.</p>
      <p>This methodology enabled us to create a unified temporal framework conducive to analysis,
accurately reflecting the progression of module timelines.</p>
      <p>As a result, we obtained a dataset1 consisting of 34 features and 1 718 983 samples,
encompassing students’ demographic information, assessment scores, and interactions with the VLE
for a specific time  , corresponding to each student  within a given course  and module  .
Table 1 provides a comprehensive description of all features2. Additionally, categorical features
were converted to numerical representations, with mappings included for reference in the last
column. The target classes—’Withdrawn’, ’Fail’, ’Pass’, and ’Distinction’—were encoded as 0,
1, 2, and 3, respectively. It is noteworthy that the data exhibits a significant imbalance, with a
substantial prevalence of records associated with students who passed the final examination.
The class distribution is as follows: ’Pass’ (1 022 760 samples), ’Distinction’ (308 642 samples),
’Fail’ (227 550 samples), and ’Withdrawn’ (160 031 samples) [16].
1Casalino, G., Castellano, G., Zaza, G. (2024). A New Dataset for Streaming Learning Analytics [Data set]. Zenodo.
https://doi.org/10.5281/zenodo.14003233
2Please note that the features ‘dualpanel‘, ‘folder‘, ‘repeat activity‘, and ‘html activity‘ were excluded from the dataset
due to the absence of recorded interactions.</p>
    </sec>
    <sec id="sec-3">
      <title>3. Experiments and Discussion</title>
      <p>Experiments were conducted to evaluate the suitability of the new dataset for stream algorithms.
To achieve this objective, three sets of experiments were designed, each utilizing diferent
temporal units: months (M), trimesters (T), and semesters (S). The data was segmented into
intervals based on these temporal units, with groupings established every 30 days (for months),
90 days (for trimesters), and 180 days (for semesters). This segmentation resulted in 30 groups
for the monthly analysis, 10 for the trimester analysis, and 5 for the semester analysis.</p>
      <p>Given that the target classes ’Withdrawn’ and ’Distinction’ are underrepresented in
comparison to the more prevalent classes ’Fail’ and ’Pass’, we opted to consolidate these categories into
a binary classification scheme 3. Specifically, ’Fail’ was combined with ’Withdrawn’, while ’Pass’
was merged with ’Distinction’. This approach resulted in a dataset comprising 1 331 402 total
samples for the Pass class and 387 581 samples for the Fail class.</p>
      <p>Figure 1 presents statistics regarding class distribution across the various time segments for
the three experimental settings: months (A), trimesters (B), and semesters (C). In the figure, the
Pass class is represented in red, while the minority class, Fail, is depicted in blue.</p>
      <p>It is important to note that the size of the chunks is not uniform across the three settings;
rather, the number of samples within each chunk is contingent upon the quantity of interactions
recorded within a given time period. Furthermore, data variability tends to increase as the
temporal unit  is reduced. For instance, in the semester setting, the ratio between the two
classes remains relatively consistent across the five chunks. Conversely, in the trimester setting,
we observe variations in the distributions of the two classes across the diferent chunks. This
variability becomes even more pronounced in the monthly data, where Fail cases are significantly
outnumbered by Pass cases in some chunks.</p>
      <p>Temporal patterns emerge from the analysis, revealing periods characterized by elevated
levels of interaction, which correspond to higher incidences of both Failures and Successes.
Following these peaks, the numbers tend to decline over subsequent months before experiencing
another resurgence.</p>
      <p>The Online Bagging algorithm was employed in this study due to its eficacy in managing
3The following mapping was adopted for the binary classification: Mapping = {‘Withdrawn’: 0, ‘Fail’: 0, ‘Pass’: 1,
‘Distinction’: 1}. In this scheme, ’Withdrawn’ and ’Fail’ were both mapped to 0 (indicating the Fail class), while
’Pass’ and ’Distinction’ were mapped to 1 (indicating the Pass class).
evolving data streams through the application of ensemble methods, which enhance predictive
performance and robustness in dynamic environments compared to other stream algorithms
[17]. Online Bagging is an ensemble learning technique that adapts the conventional Bagging
method for streaming data. Unlike traditional Bagging, which utilizes multiple bootstrap
samples derived from a static dataset, Online Bagging processes data incrementally. As new
data points are introduced, the algorithm continuously updates its models without the need
to store or revisit prior data. The model is retrained multiple times with assigned weights for
each incoming data point, thereby emulating the bootstrapping process. This characteristic
renders it particularly suitable for real-time or streaming data scenarios. In our implementation
of Online Bagging and the associated experiments, we utilized CapyMOA4, a Python framework
built upon the well-established MOA (Massive Online Analysis).</p>
      <p>To accurately simulate the real-time nature of streaming data, we employed a train-test
evaluation method specifically designed for stream data in these experiments. This approach
sequentially utilizes each chunk of data for both training and testing purposes. Specifically, the
model is trained on the -th chunk and subsequently tested on the  + 1-th chunk, allowing for
progressive learning from the stream. This procedure is repeated for all data chunks, resulting
in  − 1 training and testing cycles for a total of  chunks. This methodology ensures that the
model is assessed on unseen data, mirroring real-world scenarios where predictions are made
based on future data after prior learning.</p>
      <p>It is important to note that the features ‘id_student‘, ‘date‘, and ‘date plus‘ were excluded from
the computations to prevent bias in the results. Additionally, the ‘feature score‘ was removed
due to the presence of numerous missing values resulting from incomplete assessments.</p>
      <p>Standard classification metrics were employed to evaluate the model’s performance after
processing each chunk. These metrics include accuracy, precision, recall, and F1-score, providing
a comprehensive assessment of the classifier’s performance as it sequentially processes data
over time.</p>
      <p>Table 2 presents the average classification performance along with the standard deviation
across all chunks for each of the three experimental settings (months, trimesters, and semesters),
reported separately for the two classes: Fail and Pass.</p>
      <p>Given the significant class imbalance present in the dataset, accuracy as a metric is deemed
unreliable, as it tends to be biased toward the majority class. Consequently, the following
analysis emphasizes the F1-score, precision, and recall for both classes. The results indicate that
the model encounters challenges in accurately identifying the Fail class, consistently recording
low values across all three experimental settings. In contrast, the Pass class demonstrates high
4CapyMOA: https://capymoa.org/
scores for all three metrics. Notably, when employing the "semester" temporal unit, the recall for
the Pass class reached 93.63%, signifying that nearly all samples labeled as Pass were correctly
identified by the model.</p>
      <p>A similar trend is evident across all three experimental settings: the models exhibit proficiency
in recognizing the majority class while struggling with the minority class. Although the
optimal results were obtained with semester-based data—likely due to the more comprehensive
information contained within each semester—the performance associated with monthly and
trimester data was only marginally lower. This observation suggests that the model efectively
learned the underlying data structure and utilized it competently for predictions.</p>
      <p>Nonetheless, the recall values for the Fail class remain notably low, particularly with
semesterbased data, where it was recorded at 14.31% with considerable variance. There is, however, a
slight improvement in recall for the Fail class when using monthly and trimester data, achieving
values of 20.92% and 22.88%, respectively.</p>
      <p>To further analyze the average performance across all chunks in each experimental setting,
Figure 2 presents a Violin Plot of the F1 scores for the two classes: 0 (Fail) and 1 (Pass). Violin
plots efectively illustrate the data distribution across diferent categories by integrating features
of both box plots and density plots. The central dot in the plot represents the median, while
the thick bar indicates the interquartile range. The shapes extending from either side of the
bar illustrate the data distribution, with the width signifying data density. Wider sections of
the violin indicate higher data concentration, whereas narrower sections reflect sparser areas.
Violin plots facilitate comparisons of central tendency and data distribution across multiple
groups.</p>
      <p>Figure 2 corroborates the observations regarding the average F1 values for the Pass and Fail
classes across the three temporal settings. This figure also elucidates the distribution of F1 scores
obtained from diferent data segments within each experimental scenario. Elongated violins
indicate high variability in the data, while wider and flatter violins suggest low variability,
signifying that the model is robust to changes in the data. It is important to consider that the
number of data segments varies across the three scenarios (30 for monthly data, 10 for trimester
data, and 5 for semester data), which may influence the interpretation of the results.</p>
      <p>Furthermore, as illustrated in Figure 1, while the Pass class consistently represents the
majority in every segment across all time periods, the monthly dataset exhibits several instances
of data drift. This drift significantly reduces the representation of the minority Fail class, thereby
complicating accurate predictions (e.g., in segments X and Y). Although these drifts are still
present in the trimester data, they occur to a lesser extent and are absent in the semester dataset.
The more frequent drifts observed in shorter time intervals elucidate the more elongated shape
of the violins for these periods.</p>
      <p>Interestingly, the variability for the Pass class is minimized, with F1 scores deviating only
slightly from the average despite some variance. In contrast, the Fail class exhibits considerably
higher variability. Notably, in the semester-based experiments, the elongated violin for the Fail
class indicates that, despite the larger data size compared to shorter periods, the data remains
insuficiently informative for constructing an accurate predictive model for this minority class.</p>
      <p>In summary, the new dataset proves valuable for predicting student outcomes. However, it is
crucial to ensure that the data is balanced or that the diferences between the two classes are
minimized to achieve acceptable classification performance for both the Fail and Pass categories.
Moreover, the results indicate that the various temporal periods provide adequate information
for the classifier, thereby enabling continuous monitoring of student activities. This capability
allows for timely interventions when a student’s performance declines, facilitating support
before issues escalate.</p>
    </sec>
    <sec id="sec-4">
      <title>4. Conclusions and future work</title>
      <p>Recent studies have indicated that stream algorithms can efectively monitor student learning
within Virtual Learning Environments (VLEs) when incorporating temporal information.
However, a significant limitation exists due to the lack of student data containing such temporal
information. To address this issue, this study introduces a novel dataset derived from the Open
University Learning Analytics Dataset (OULAD). We manipulated the timing information within
OULAD to establish a unique temporal framework for student interactions with the platform.</p>
      <p>To evaluate the utility of this dataset for predicting student outcomes in a streaming
context, we conducted experiments using an online stream algorithm known as Online Bagging,
implemented via the Python library CapyMOA.</p>
      <p>Three experimental settings were designed, where data subsets were grouped by diferent
temporal units: month, trimester, and semester. The results indicated that the classifier struggled
to recognize the Fail class, which is underrepresented compared to the Pass class. However, the
Pass class was correctly identified, achieving F1 scores of approximately 80% across all three
settings. Despite numerous fluctuations in the data—variability that increased as the temporal
units decreased—the classifier demonstrated robustness in recognizing the Pass class. This
ifnding highlights the potential of stream algorithms to efectively monitor student progress
over time.</p>
      <p>Research has shown that the choice of temporal units can significantly influence the outcomes
of classification models aimed at predicting student performance. Our study revealed that even
the smallest temporal unit of 30 days (equivalent to a month) yielded results comparable to those
obtained with larger units. This suggests that data from a single month is suficient for capturing
learning patterns that are instrumental in predicting student performance, particularly when
utilizing adaptive and incremental stream algorithms.</p>
      <p>Nevertheless, this work represents an initial exploration of the new dataset. Future research
will further investigate the application of stream algorithms within the educational domain,
with a focus on enhancing their efectiveness and evaluating their applicability in real-time
scenarios. This will involve analyzing data on a daily or weekly basis to promptly identify
students at risk of failure and facilitate early intervention. Additionally, we aim to explore
methods for enhancing the interpretability and reliability of results derived from streaming
data. Finally, we plan to integrate resampling techniques into the streaming data context to
address the challenges identified in this study, particularly those related to class imbalances and
overall classification performance.</p>
    </sec>
    <sec id="sec-5">
      <title>5. Acknowledgments</title>
      <p>G. Castellano and G. Zaza acknowledge funding support from the FAIR - Future AI Research
(PE00000013) project, Spoke 6 - Symbiotic AI (CUP H97G22000210007), under the NRRP MUR
program funded by NextGenerationEU. All authors are members of the INdAM GNCS research
group.
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