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  <front>
    <journal-meta>
      <journal-title-group>
        <journal-title>Ital-IA</journal-title>
      </journal-title-group>
    </journal-meta>
    <article-meta>
      <title-group>
        <article-title>Low-achievement risk assessment with machine learning</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>Andrea Zanellati</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Stefano P. Zingaro</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Maurizio Gabbrielli</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <aff id="aff0">
          <label>0</label>
          <institution>Università di Bolonga</institution>
          ,
          <addr-line>via Zamboni 33, Bologna, 40126</addr-line>
          ,
          <country country="IT">Italy</country>
        </aff>
      </contrib-group>
      <pub-date>
        <year>2023</year>
      </pub-date>
      <volume>3</volume>
      <fpage>29</fpage>
      <lpage>31</lpage>
      <abstract>
        <p>In this work, we propose a method for assessing the risk of low-achievement in secondary school with data collected from the Italian ministry of education. Low-achievement is a phenomenon whereby a student, despite completing his or her education, does not reach the level of competence expected by the school system. We train three machine learning models on a large, real dataset through the INVALSI large-scale assessment tests and compare the results in terms of predictive and descriptive performance. We exploit data collected in end-of-primary school mathematics tests to predict the risk of low-achievement at the end of compulsory schooling (5 years later). The promising results of our approach suggest that it is possible to generalise the methodology for other school systems and for diferent teaching subjects.</p>
      </abstract>
      <kwd-group>
        <kwd>eol&gt;low-achievement</kwd>
        <kwd>performance prediction</kwd>
        <kwd>assessment test</kwd>
        <kwd>machine learning</kwd>
      </kwd-group>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>1. Introduction</title>
      <p>of school efect on their skills acquisition.</p>
      <p>
        An important indicator for school dropout is the ELET
Low-achievement at school is a widespread phenomenon rate, which measures the percentage of Early Leavers
which has long-term consequences, both for the individ- from Education and Training [6]. It measures a severe
ual and for society as a whole. In 2016, above 28% of condition of educational exclusion which refers to young
students across Organization for Economic Co-operation people between 18 and 24 with a qualification lower than
and Development (OECD) countries underscored the min- upper secondary. Early leavers from education and
trainimum level of proficiency in at least one of the three core ing are more likely to be unemployed or employed in
subjects according to the Programme for International low-paid jobs with few or no prospects for training and
Student Assessment (PISA), which are English reading further career progression; they are more prone to social
and comprehension, mathematics, and science [
        <xref ref-type="bibr" rid="ref1">1</xref>
        ]. Low- exclusion and to experience lower levels of health,
wellachievement is strongly related to school dropout, i.e., being and life satisfaction; they are also more likely to
the discontinuation of education [2], and impact on the experience limited civic participation. In [7] the
Eurocultural and professional growth of the individual and pean Commission indicated as one of the main targets to
citizen [3, 4]. Indeed, school performance in first grade is be achieved in education the reduction of the ELET rate
already a significant indicator of future high dropout risk. from 15% to 10% in the decade 2010–2020. While this
In 2019, a study conducted by the National Institute for target was reached in several European countries, Italy
Assessment of the Education System (INVALSI) found in 2019 still had an ELET rate of 13.5%[8].
that 20% percent of Italian students had a lower-than- To counteract dropout as soon as possible and to
deexpected achievement and, eventually, dropped out of tect low-achievement, we address the following research
school [5]. This way, despite the exterior appearance questions:
and, in some cases, despite the suficient marks, the
students do not reach the adequate level of knowledge which RQ1 Is it possible to quantitatively
reprelater on will be needed to successfully continue the stud- sent a student’s knowledge level and build
ies or to start a professional career. In this perspective, a model of his or her skill attainment?
low achievement can be considered an “implicit” form
of school dropout: although some students do not occur
into explicit early leaving from school, the result is a lack
      </p>
      <sec id="sec-1-1">
        <title>RQ2 Is it possible to develop a suitable AI</title>
        <p>tool to predict, at an early stage, the risk
of low-achievement at secondary school
for primary school students?</p>
      </sec>
      <sec id="sec-1-2">
        <title>In the following, we present a case study, focusing on</title>
        <p>the Italian context and using data collected from the
INVALSI national large-assessment tests in mathematics. In
particular, from these tests, we aim to extract the relevant
features related to students’ learning in terms of their
skill and competence level performance.</p>
        <p>In RQ2, we refer to “early stage” meaning to detect
risk as soon as possible, i.e., several years in advance, so</p>
      </sec>
    </sec>
    <sec id="sec-2">
      <title>3. Methodology</title>
      <p>that appropriate countermeasures can be taken, and to
design an intervention aimed at reducing risk when it
is detected. Concretely, we develop three models able The INVALSI dataset is the result of a large-scale
assessto predict the risk of low-achievement at K-10, using ment administered in Italy since the school year 2002/03
student data at K-5. at the levels K-2, K-5, K-8, K-10, and K-13. Students are</p>
      <p>
        In selecting the models, we strive for a balance between tested in Italian, Maths and English. In addition to this,
descriptive and predictive performance. Indeed, we want there is a student-survey aimed at gathering
informaour solution to be both interpretable and robust. Hence, tion on the social, economic and cultural context. A
we consider state-of-the-art machine learning techniques strength point of the dataset is represented by the
posthat proved to be efective in preliminary experiments [
        <xref ref-type="bibr" rid="ref22">9</xref>
        ]: sibility to longitudinally link data collected in diferent
random forests and neural networks [
        <xref ref-type="bibr" rid="ref13">10, 11</xref>
        ]. On the one school years [22] starting from 2011. In our case study,
hand, we exploit random forests to extract rules that we considered data on maths test from two cohorts of
facilitate the process of interpreting the outcomes of the students: K-5 of the 2012/13 school year and K-5 of the
research and, on the other hand, we test neural networks 2013/14 school year. For the same students, we collected
for flexibility, e.g., exploring non-linear correlations, and data from five years later at grade K-10, to be used for
performance gain. the definition of the low-achievement target, i.e., the
students grade in the test is less than or equal to 2 on a scale
from 1 to 5. After merging K-5 datasets with their
corre2. Related work spondent K-10 targets, the K-5 2012/13 cohort is made
up of 351746 students, while the K-5 2013/14 cohort of
Low-achievement is a widely studied phenomenon in the 354987 students.
social sciences and education [12, 13]. The problem has There are several features in the dataset and we
apalso been addressed in terms of predictive models for low- plied a feature selection process to determine a subset
achievement—or dropout risk—for both high school and of relevant features. The datasets also contain a boolean
college students. These models exploit diferent machine feature for each test item, where the students’ answers
learning techniques, including supervised learning, e.g., correctness are recorded. To enable the use of our
prerandom forests, support vector machine and Bayesian dictive models on diferent cohorts of students and to
network, unsupervised learning, e.g., k-means and hi- provide a coherent representation of their learning in
erarchical clustering, and recommender systems, e.g., terms of areas of knowledge and skills, it is necessary to
collaborative filtering [ 14, 15]. Moreover, several kinds release the dataset from the individual items that
constiof data have been used to tackle the problem. In [16] tute a certain test. Therefore, we used a knowledge-based
the dataset for building the predictive model uses de- approach considering the items classification in terms of
mographic data of the students and their grades. Other areas, processes and macro-processes according to the
studies are based on students performance, i.e., grades, INVALSI framework for the design of math tests.
collected during first semester courses [ 17, 18]. Some in- In Table 1, we give for reference an overview of the
clude behavioural data supplemented with other features areas, processes, and macro-processes that have been
related to learning results [19], in a mix of cognitive and used in the encoding of the questions.
non-cognitive characteristics. In some studies data col- We define one new variable for each area, process,
lected through large-scale assessment tests were used to and macro-process. Each of these new features takes
design predictive models of student performance through the value corresponding to the percentage of correct
several machine learning techniques. In [20], for exam- answers provided by the student for that specific group of
ple, the authors refer to data collected through the PISA items, namely, correctness rate. Last, we concatenate the
international large-scale assessment tests. computed values to obtain a new flattened representation
      </p>
      <p>
        In this scenario, we aim to contribute to the research of learning, where each item is a possible indicator and
ifeld of AI-based education solutions by presenting a case not its unique representative. Following our strategy, we
study for predicting the risk of low-achievement of high represent each student’s learning in the space of ffiteen
school students using their performance data collected (15) dimensions, as shown in Table 2.
during primary school. As a minor contribution, we We use two techniques to develop our AI-based tool.
extract features directly related to students’ learning in The first one is Random forest (RF) [ 10], which is widely
terms of knowledge and skills, privileged indicators for used in Educational Data Mining for the high degree of
the study of learning [21], thus proposing a knowledge- explainability and efortless interpretation of the results.
based method for encoding students’ learning. We believe We trained our models through bootstrap aggregating
that this element can improve the interpretability of the (bagging) to reduce the overfitting of dataset and increase
results and make this tool useful for students, teachers precision. To tune the model, we performed a grid search.
and instructional coordinators. The second technique is based on neural networks,
Areas
(NU) Numbers
(SF) Space and figures
(DF) Data and forecasts
(RF) Relations and functions
Process
(P1) Know and master the specific contents of mathematics
(P2) Know and use algorithms and procedures
(P3) Know diferent forms of representation and move from one to the other
(P4) Solve problems using strategies in diferent fields
(P5) Recognize the measurable nature of objects and phenomena in diferent
contexts and measure quantities
(P6) Progressively acquire typical forms of mathematical thought
(P7) Use tools, models and representations in quantitative treatment
information in the scientific, technological, economic and social fields
(P8) Recognize shapes in space and use them for problem solving
Macro-process
(MP1) Formulating
(MP2) Interpreting
(MP3) Employing
4. Experimental results
which has recently become widespread also in the field
of Educational Data Mining and has also been applied
in predictive models for student performance [23]. To We carried out all the experiments using the Google
deal with our hybrid dataset, we firstly include a prepro- Colaboratory Notebook environment, with the Python
cessing step, aimed at encoding the values of categorical programming language and popular machine learning
variables into numerical values with a “one-hot” encod- libraries, such as scikit-learn and pandas.
ing algorithm. After preprocessing, we implemented two The dataset for all the experiments was pre-processed
neural networks based on diferent data transformation cleaning features with many missing values, highly
corapproaches. Categorical Embeddings (CE), is a neural relation (computed by 2 measure above 0.5) or
specifnetwork that treats the input depending on its type: cat- ically referred to a cohort of students, preventing the
egorical inputs are passed through an embedding layer, model to be transferred to new cohorts (e.g., identification
numerical ones are fed to a dense layer. Feature Tokenizer code for a class). This features selection process, together
Transformer (FTT) [
        <xref ref-type="bibr" rid="ref13">11</xref>
        ] is able to identify the input or the with the engineering of the features related to the items in
group of inputs that most influence the output, thanks to the tests, results in a set of 34 features, which refers both
attention maps. It is a more complex architecture that ex- to socio-economic and cultural context, demographic
ploit a feature tokenizer function to extract tokens from data and learning dimension. For the definition of the
the input and then fed these tokens to a Transformer training set we used the data from 2012/13 K-5 cohort. For
architecture [24] for classification. the models based on neural networks we split this cohort
to generate both training and validation sets (split in 80%
and 20% respectively). Finally, we used the K-5 2013/14
cohort to test and measure the model performance. This
allowed us to evaluate the validity of the proposed
learning encoding that is, the efectiveness of abstraction from
specific items to learning in terms of areas, processes
and macro-processes. The dataset is unbalanced between
underachievement/non-underachievement classes;
therefore balancing techniques were applied. In the
development of the RF models, a random undersampling
technique was used, implemented in the imblearn library.
      </p>
      <p>We trained neural networks using a weighted random
sampler, that samples the data to balance classes ratio in
the training batches.</p>
      <sec id="sec-2-1">
        <title>Finally, we want to deepen the interpretability of the re</title>
        <p>sults of our models, by analysing the feature importance
computed on RF model and comparing it with the
interpretation of the weights that define the neural networks
we have used.</p>
      </sec>
    </sec>
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