<!DOCTYPE article PUBLIC "-//NLM//DTD JATS (Z39.96) Journal Archiving and Interchange DTD v1.0 20120330//EN" "JATS-archivearticle1.dtd">
<article xmlns:xlink="http://www.w3.org/1999/xlink">
  <front>
    <journal-meta />
    <article-meta>
      <title-group>
        <article-title>Developing Machine Learning Models for the Analysis of Citizens' Contributions from E-Participation⋆</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>Marten Borchers</string-name>
          <email>marten.borchers@uni-hamburg.de</email>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Delzar Habash</string-name>
          <email>delzar.habash@dlr.de</email>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Eva Bittner</string-name>
          <email>eva.bittner@uni-hamburg.de</email>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <aff id="aff0">
          <label>0</label>
          <institution>Deutsches Zentrum fur Luftand Raumfahrt e.V</institution>
        </aff>
        <aff id="aff1">
          <label>1</label>
          <institution>University of Hamburg</institution>
          ,
          <addr-line>Mittelweg 177, 20148 Hamburg</addr-line>
          ,
          <country country="DE">Germany</country>
        </aff>
      </contrib-group>
      <pub-date>
        <year>2025</year>
      </pub-date>
      <abstract>
        <p>Citizen participation is increasingly relevant in acquiring local knowledge for urban projects. However, the increasing number of participants has created a problem of data overload, as manual analysis is hardly feasible due to its expense, time intensity, and slowness. AI and ML can help reduce or solve this issue. However, due to the lack of proper ML-based approaches, we investigate how textual contributions from citizens can be analyzed using machine learning techniques. To achieve this, we followed the knowledge discovery in the database framework, collected data, and trained several machine learning models, which we analyzed and compared. Our ifndings demonstrate that urban development contributions often cover multiple topics, making classification challenging, which also corresponds to the length of citizens' contributions. Transformer models, however, show remarkable precision when compared to SVM models. With our findings, we contribute to the analysis of citizen contributions to support democratic processes and scalable citizen participation.</p>
      </abstract>
      <kwd-group>
        <kwd>eol&gt;Citizen Participation</kwd>
        <kwd>Machine Learning</kwd>
        <kwd>Urban Planning</kwd>
        <kwd>Data Analysis</kwd>
        <kwd>Knowledge Discovery in Databases</kwd>
      </kwd-group>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>1. Introduction</title>
      <p>
        Today, most of the global human population lives in urbanized areas, and this trend is expected to
continue until 2050 [
        <xref ref-type="bibr" rid="ref1">1</xref>
        ]. However, this growth has led to dificulties for urban developers and planners,
who aim to plan projects in the most eficient way possible, thus saving resources, improving the quality
of life [
        <xref ref-type="bibr" rid="ref2">2</xref>
        ], and increasing sustainability [3]. Planning such projects comes with its own set of problems [4].
Ideally, the main stakeholders should be the local citizens since they live in the area concerned. However,
citizens’ wishes may conflict with the priorities and objectives of other stakeholders like local businesses
and industries, development or construction companies, environmental and conservation agencies or
groups, local government policies, and more [5]. As a reaction, governments involve citizens in urban
planning to increase transparency, trust, acceptance, and the real-world benefit of projects [6].
      </p>
      <p>However, electronic participation (e-participation) with websites and comprehensive participation
platforms, such as Decide Madrid [7] and DIPAS [8], among others, lacks automatic analysis systems
that can handle thousands of citizen contributions to support urban experts in subsequent processes.
For example, in 2019, a Scottish portal generated around 16,000 responses [9]. The absence of automatic
analysis approaches and the fact that the gathered citizen contributions are mainly in free-text [10]
increase costs and errors during the analysis process, e.g., inconsistencies. Therefore, new solutions are
required to automatically analyze citizens’ contributions [11].</p>
      <p>The scientific literature describes demands and requirements, e.g., summarized and focused on
sentiment analysis, keyword search, and clustering [12], and presents initial solutions for machine
learning models (ML). Natural language processing (NLP) is crucial in handling textual data. Despite
the significant strides in the field of NLP, the processing of participation data with NLP, particularly
classification, remains understudied, which can be attributed to a lack of publicly available data.</p>
      <p>Therefore, we build upon the existing knowledge of artificial intelligence (AI), ML, and NLP in citizen
participation to examine the following research question (RQ).</p>
      <p>RQ: How should textual citizens’ contributions from e-participation be classified with machine
learning techniques?</p>
      <p>To answer the RQ, we pursue a practical and data-oriented approach as described by the
Knowledge Discovery in Databases Framework (KDD), which defines a structured process for gaining new
knowledge from data and ML models [13]. Therefore, we collected a dataset from e-participation and
manually labeled it. We then trained several ML models, which were compared to each other and
further analyzed to increase their accuracy, as described and elaborated on in the following sections.</p>
    </sec>
    <sec id="sec-2">
      <title>2. Theoretical Foundation</title>
      <p>Citizen participation can be defined as an involvement characterized by interactive and iterative
deliberation processes among citizens and government oficials [ 14]. Another definition, provided by
Boudjelida et al., is "a form of democracy in which citizens are part of the decision-making process
about the development of their society" [15]. Both show that solutions or views imposed on the public
top-down by leaders and experts are no longer considered optimal and that governing institutions need
to build networks to link them with the public to keep up with modern complexities to which many
agree [16].</p>
      <sec id="sec-2-1">
        <title>2.1. Minimum Viable Process for Citizen Participation</title>
        <p>Stelzle et al. [17] proposed a process model for incorporating citizens and other stakeholders in urban
projects, which has also been tested and applied in practice, called the minimal viable process (MVP),
summarized in Figure 1.</p>
        <p>The MVP begins with (1) initiating the urban project and assembling a project team. In step (2)
(co-brief), the project lead’s objectives are documented and prioritized with stakeholders, including
designers and planning authorities, focusing on project scope and citizen participation. This sets the
stage for (3) co-design, where citizen participation occurs through various methods like information
booths, workshops, (online) surveys, contests, social media, and participation platforms and therefore
contributes huge amounts of textual data [16].</p>
        <p>At the end of the co-design process, results are evaluated to determine the project’s strategic alignment.
In step (4), project visions developed by architects and urban planners are published to gather further
feedback from citizens through voting and comments on digital platforms. Steps (5) and (6) involve
analyzing comments and voting results, which are then integrated (7) into a comprehensive urban
project design. Finally, this design must be approved (8) by the project lead and planning authorities (9)
to ensure compliance with regulations and facilitate permit acquisition [17].</p>
      </sec>
      <sec id="sec-2-2">
        <title>2.2. Challenges in the Analysis of Citizens’ Contributions</title>
        <p>Citizens’ inputs generated during participation must be analyzed and evaluated by experts (cf.
Figure 1) [12]. Experts face challenges in this context, as the number of participants in e-participation
and on participation platforms has increased significantly [ 9]. This creates an overload of information
for subsequent processes, including analysis, sense-making, and the development of shared ideas and
visions [18].</p>
        <p>A larger number of participants is beneficial for e-participation because it generates broader, more
diverse, and more comprehensive knowledge [19]. However, massive participation events, such as the
U.S. Federal Communications Commission’s net neutrality implementation, which gathered over 450,000
comments [20], showcase how the volume of contributions can increase. Experts often lack the resources
and skills to exploit this knowledge pool [21]. The extensive data volumes pose significant challenges
for processing, and the resulting information overload becomes a real issue. Real-time analysis could
significantly reduce the time between analysis and decision-making [ 22]. Another challenge in analyzing
citizens’ contributions is the individual and qualitative processing [12]. Evaluators can build on reusable
and standardized methods and categories, saving time and financial resources [16].</p>
      </sec>
      <sec id="sec-2-3">
        <title>2.3. AI and ML for analyzing E-Participation Data</title>
        <p>AI encompasses various technical approaches that facilitate the automatic execution of tasks that mimic
human capabilities [23]. Within this domain, ML refers to algorithms that enable models to learn from
to make predictions, classifications, or clustering [ 24]. NLP is a subfield of AI and ML that focuses
specifically on analyzing and understanding human language, making it a valuable tool for interpreting
citizen contributions in free-text formats. Despite the increasing interest in leveraging ML and NLP for
e-participation initiatives, practical applications remain limited [10].</p>
        <p>Recent studies highlight the potential of ML and NLP in addressing the challenge of information
overload on e-participation platforms. Arana-Catania et al. [21] proposed utilizing these technologies
to analyze citizens’ interests, fostering increased participation and enhancing user experience on urban
platforms. Similarly, Lieven et al. [8] emphasized the eficiency of using ML to evaluate complex and
unstructured citizen inputs by generating automatic summaries. Moreover, researchers have examined
clustering models to analyze sentiments from social media contributions, aiding moderators in real
time [25]. However, the ambiguity inherent in short or keyword-based contributions poses challenges
for accurate interpretation. Romberg et al. [22] provide an analogous approach, illustrating the training
of a classification model with citizen inputs from a mobility project to establish a preliminary analysis
framework. These studies collectively underscore the promise of ML and NLP in enhancing the analysis
of citizen contributions.</p>
      </sec>
    </sec>
    <sec id="sec-3">
      <title>3. Research Methodology</title>
      <p>As stated by the RQ, ML models have not yet produced sufiecient results for analyzing citizens’
contributions from e-participation. Given the importance of data, e.g., citizen contributions, we follow
the Knowledge Discovery in Databases Framework (KDD) [13].</p>
      <sec id="sec-3-1">
        <title>3.1. Knowledge Discovery in Databases Framework</title>
        <p>The framework delineates a systematic methodology for iteratively deriving insights or knowledge
from data [26]. This framework operates on the premise that IT systems can document data related
to usage, user behaviors, and outcomes, which, when analyzed, facilitate the making of inferential
statements and a deeper understanding. Furthermore, a robust dataset enables the training of new ML
models. Knowledge generated through the framework is expected to be generalizable, non-trivial, novel,
useful, and comprehensible [26].</p>
        <p>The KDD is distinguished by its structured process, as illustrated in Figure 3.1, and is critically
relevant in today’s data-driven world [27]. Unlike more pragmatic and flexible methodologies focused
on resolving specific business challenges, the KDD emphasizes a rigorous protocol that includes data
cleansing and standardization, thereby facilitating the replication and verification of results by other
researchers. In the initial phase, the goal and domain knowledge are defined. Subsequently, the KDD
procedure is traversed in five phases (cf. Figure3.1). In the selection phase, the data suitable for the goal
are chosen. In the preprocessing phase, data quality is evaluated and cleaned. The data is converted into
a format that ML algorithms can process in the transformation phase. In the data mining or ML phase,
algorithms are selected to search for patterns or insights in the data [26]. The KDD process focuses on
the data, which is why ML or NLP can be employed. In the interpretation and evaluation phase, the
results of the ML algorithm are finally analyzed and visualized [13].</p>
      </sec>
      <sec id="sec-3-2">
        <title>3.2. Application of the Framework</title>
        <p>In applying the framework, we elicited a dataset of citizen contributions to urban planning in Germany.
We archived that by combining available data from two past participations. One was implemented in
eastern Germany, and the other in middle Germany. Both focused on the reconstruction of buildings:
the first was a university campus in a larger city, and the second was a school in a smaller city. Together,
the dataset comprises nearly 18,000 contributions from citizens.</p>
        <p>In the selection step, we conducted a detailed examination of the data set to understand its nature
and properties. This preliminary analysis is critical, laying the groundwork for all subsequent stages of
the framework process. In the preprocessing step, we cleaned the data, addressed irregularities, and
handled missing values by manually correcting or removing them to create a uniform dataset of 17,031
entries as shown in Table 1.</p>
        <p>The transformation step was extensive. To train a classification model, we had to label all entries.
This was achieved with the help of two hired and trained students who labeled all data manually
according to the ten categories as shown in Table 1. Both students labeled the data according to a
description of the categories in the literature [12, 22]. The last category was used to count unclear and
not understandable contributions. The prepared data was formatted appropriately for text categorization,
involving organizing the texts and their corresponding labels into a structured dataset.</p>
        <p>In the data mining step, we conduct various experiments to study the data characteristics and
identify potential challenges that impede efective text categorization. These experiments also helped
in understanding the baseline performance of NLP techniques on the data [24]. In the evaluation and
interpretation step, we focused on the performance of the developed ML models and interpreted their
efectiveness in classifying contributions within citizen participation. ML Prototypes were tested, and
an ensemble approach was favored due to the unbalanced and multi-topic nature of our dataset [28].</p>
      </sec>
    </sec>
    <sec id="sec-4">
      <title>4. Evaluation and Findings</title>
      <p>The dataset under investigation was partitioned into a training set (80%) and a testing set (20%) and was
subjected to classification using five diferent classifiers, as shown in Table 2. The dataset underwent
several sequential transformations to investigate the efects of the preprocessing techniques on the
performance of successive transformations. Each subsequent transformation builds upon the output of
the previous one.</p>
      <p>The initial condition involved no preprocessing. Therefore, it contained only the pure text, vectorized
using the wiki corpus dataset [29]. The next step involved normalizing capitalization so that the holder
text is in lowercase to increase semantic similarity, and the last step was to stem the tokens, ensuring
that words are converted into their base form. The performance of the classifiers was evaluated using
the F1 score, a harmonic mean of precision and recall calculated via the confusion matrix (true-positive,
false-positive, true-negative, and false-negative), which is particularly useful in situations where a
balance between these metrics is desired [30]. This measure is crucial when dealing with datasets that
may have an imbalance in class distribution or when the costs of false positives and false negatives are
significant.</p>
      <p>In the training and analysis conducted, support vector machine (SVM) and logistic regression exhibited
superior performance. This robust performance was observed across various stages of text preprocessing.
Naive Bayes showed notable improvement when stop words were removed, consistent with their
probabilistic foundations, which can be sensitive to irrelevant features. Decision trees, which are
generally weaker classifiers for text data but robust against outliers, showed poor performance across all
text variants, whereas ensemble methods, such as gradient boosting, demonstrated enhanced outcomes.</p>
      <p>Further analysis was conducted using the same classifiers as before. Similar preprocessing steps were
applied except for removing special characters, which had already been conducted during data cleaning.
SVM again performed the best among the classifiers, though the F1 scores indicated that the classifiers
struggled more with citizens’ contributions than with the initial dataset. Attempts to optimize the
SVM’s hyperparameters did not yield significant improvements, with the F1 score plateauing around
0.7. A fascinating insight was gained by excluding entries labeled as "undefined," which typically
represent contributions that are too vague or ambiguous to be classified meaningfully. This exclusion
led to a noticeable improvement in the SVM’s performance, from an F1 score of 0.69 to 0.75. This
improvement underscores the importance of dataset quality and the impact of ambiguous data on
classifier performance.</p>
      <p>The trained SVM models concentrated on the length of citizens’ contributions to identify possible
patterns that ML models could abstract. The existing literature suggests that longer texts generally
enhance classifier performance. However, this assumption requires validation within the domain of
citizen participation [28], where texts are typically quite short, nuances difer significantly, and empirical
data are limited. This validation involved conducting three diferent approaches to assess how text
length afects classification in this context. The data processing was conducted as before, and training
and test data were the same size as before. Notably, while previous studies measured text length by
character count or word count, this analysis used word count [31].</p>
      <p>Max. Word Count</p>
      <p>Table 3 shows that the length of citizens’ contributions influences the performance of the trained
SVM models. In columns 4 to 7, an increase in performance was observed with longer text lengths,
surpassing baseline levels and corroborating previous research [12]. However, benefits from increasing
text length plateaued after reaching eight words, with slight declines in performance thereafter. While
these findings are not definitive due to the variable dataset sizes, the trend becomes more apparent
when considering the results together, further suggesting that longer texts are leading to diminished
performance.</p>
      <p>Our findings indicated an unexpected trend: as text length increased, the F1 score generally decreased,
suggesting that longer texts might not necessarily yield better models. This was contrary to prior
assumptions [22] and raises questions about the optimal text length for training classifiers in citizen
participation. However, longer texts can also lead to poorer performance when the narrative deviates
from the central theme, complicates label assignment, or tends to be ambiguous. This pattern led to
the conception of the third training of SVM models, where a sliding text length window was applied
to the dataset to fine-tune the optimal word count range. The results, presented in Table 4, begin
with an evaluation of model performance in identifying a specific range where text length maximizes
classification accuracy.</p>
      <p>Our analysis indicated that datasets with shorter texts, as displayed in the first column of Table 5,
exhibited the highest performance. Performance consistently declined as the text length window
expanded to include longer texts. This pattern was not attributable to dataset size, as datasets with shorter
texts performed significantly better than those with longer texts of comparable size, identifying text
length as the critical variable afecting model performance. These three approaches collectively suggest
that the established research findings might not directly apply to the domain of citizen participation
data, e.g., citizens’ contributions. Although evidence was found that shorter contributions are easier to
categorize, variations could arise with diferent datasets and methodologies. This insight is valuable for
facilitators, who may encourage participants to make brief contributions for more eficient processing.</p>
      <p>To examine the impact of dataset size and the number of entries per class, we trained several additional
ML models. The F1 score of SVM models that contained at least 1,145 entries is shown in Table 6.
The classes included are Mobility, Environment, Living, Social Network, Education, and Economy (cf.
Table 1). The performance increased significantly when the dataset size increased over the trained
models up to 1,145 entries per class. Although results kept improving with each increment, diminishing
returns were noticeable, as denoted by the last row of Table 6. This suggests a performance plateau at a
certain dataset size, but the dimensions of the plateau could not be captured with the limited amount of
the citizens’ contributions.</p>
      <p>Next, we focused on transformer technology. We trained a transformer model (DistilBERT) using
default parameters from the Simple Transformers library (Python), with a batch size of 8 and over 8
epochs, achieving an F1 score of 0.759% on an evaluation dataset of 600 instances. Further trained
models, including an up-sampling of the training data with duplicates, were allowed, and datasets
were assessed at 1,200, 1,500, and 2,000 instances per class (cf. Table 1). Despite maintaining less
than 5% duplicates in test sets to minimize bias, performance increased impressively, highlighting that
transformer models benefit from larger training datasets. Incremental epochs 12 and 16 showed no
significant improvement, reinforcing the model’s responsiveness to dataset size over extended training
durations. However, an accurate classification with an F1 score of 0.92, as shown in Table 6, is promising,
even if it was only achieved with the six classes of Mobility, Environment, Living, Social Network,
Education, and Economy (cf. Table 1) due to a lack of further data.</p>
    </sec>
    <sec id="sec-5">
      <title>5. Discussion</title>
      <p>In this paper, we examined the RQ "How should textual citizens’ contributions from e-participation
be classified with machine learning techniques?" by applying the KDD Framework, which provided a
structural approach for analyzing data and deriving knowledge. To answer the RQ, we collected and
created a labeled dataset of 17,031 preprocessed entries representing real citizens’ contributions from
past participation projects, which we used to train and analyze multiple ML models.</p>
      <p>For practitioners and scientists, the dataset created can serve as a baseline for future development
and currently represents the largest dataset so far, which we hope will soon be extended. This desire is
also reflected in our findings. The trained ML models demonstrate that training is possible with an
acceptable F1 score, e.g., validity, especially for the classes in which our dataset contains many entries.
However, as urban experts and decision-makers should develop a proper vision and decide if these
sometimes very costly (construction) projects are implemented, a high validity of the analysis of data is
required, leading to the following insights.</p>
      <p>Insight 1: Only validated ML models with high validity should be used to analyze citizens’
contributions from e-participation, which requires more data.</p>
      <p>Insight 2: Preprocessing is mandatory, especially regarding the meaning of contributions and their
decomposition into sense-making pieces.</p>
      <p>Insight 3: ML model classifiers must represent the desired classes by experts in the training data
equally to increase the accuracy of the prediction.</p>
      <p>Insight 4: The length of the text contributions is decisive for the classification and must be
preprocessed as required and divided into semantic paragraphs.</p>
      <p>Considering insight 1, we cannot say which validity of an F1 score is required. However, the
trained transformer models showed the highest scores and a value above 0.9 may be enough to
support experts, while a fully automatic analysis might require an even higher validity. Insight 2
is derived from the findings of Table 2, Table 4, Table 5, and Table 6. In creating the dataset, all
contributions were divided into sense-making pieces, allowing for abstraction and highlighting
existing findings [ 32]. This is represented in the results and should be considered. Alternatively,
it is possible to predict multiple classes at once. However, the abstraction in terms of semantics
usually becomes more advanced, and the number of classes is fixed, which reduces the flexibility
of the current approach. Insight 3 highlights the demand for an equal proportion of class entries,
as shown in Table 7. Furthermore, our current results indicate that shorter texts generally yield
better classification results, although this finding may be context-specific. Nevertheless, this, along
with the increasing F1 score in Table 7, highlights the need for further data that we specify with Insight 5.</p>
      <p>Insight 5: ML model classifiers should at least contain 1,145 (preferably more) entries per class for
the training to lay a profound base for the classification.</p>
      <p>Insight 6: Transformer models are more capable of classification than SVM in terms of limited
datasets but are black box models and not transparent.</p>
      <p>Insight 7: Practitioners should deviate between transparency and eficiency of the trained model (in
SVM or decision trees) and higher accuracy (e.g., black box models like transformer models).</p>
      <p>The training of the SVM and transformer models demonstrated that while SVM models are eficient
and require shorter training times, transformer models, though slow and resource-intensive, provided
superior classification. This highlights a trade-of between eficiency and performance, influenced by
the specific needs and resources of participation facilitators. For practitioners involved in e-participation
initiatives, the implementation and development of ML models provide a significant opportunity to
enhance the analysis of citizen contributions. These models can automate the processing of large volumes
of data, enabling a more eficient and systematic approach to understanding citizens’ requirements
and sentiments [10]. By employing ML techniques, practitioners can ofer insights that drive urban
planning and policy-making processes. However, there is a pressing need to tackle all gained insight to
efectively design, implement, and interpret ML models [ 21]. This will lay the technical foundation for
the usage of ML and empower urban experts and practitioners to harness the full potential of ML in
analyzing the qualitative complexity of citizen contributions, as described in section 2.3.</p>
      <p>For governments and urban planners, understanding how ML can be developed and utilized in the
context of citizen participation is essential [22]. The integration of ML can facilitate a more democratic
and participatory governance framework where real-time data analysis aids decision-making [33]. Our
insight and the developed ML models contribute to that and establish an initial baseline for how ML is
deployed in analyzing citizen contributions. However, a critical consideration in deploying ML models
is acknowledging existing constraints, particularly concerning the availability of training data and a
standardized classification framework (cf. Insight 4). With suficient quality data and established classes,
the performance of ML algorithms is likely to be maintained. To navigate these challenges, governments
and practitioners must prioritize collecting and curating diverse datasets that accurately reflect the
spectrum of citizens’ contributions [22]. Additionally, developing standards for data classification
will help streamline analysis procedures and enhance the efectiveness of ML applications in this
domain [34].</p>
      <p>The findings from this research contribute to the scientific literature by confirming existing patterns
and revealing new insights into the nature and complexity of citizen contributions across urban
planning contexts. By systematically applying the KDD framework to analyze e-participation data,
the study yields new insights into the domain of citizen participation and e-participation, enriching
the understanding of how ML techniques can efectively categorize qualitative information [ 28]. This
exploration extends the current knowledge base and emphasizes the importance of integrating ML
technology into participatory processes [24].</p>
      <p>Moving forward, insights 4 to 6 should be interpreted as a research agenda and call for further
action from other researchers to develop ML standards, train extended and capable ML models, and
also publish their data and source code. This should include defining best practices for data handling,
processing techniques, and model evaluation, as well as the selection of models. Building trust in them
is also challenging. For instance, transformer models, such as neural networks, are not transparent,
while decision trees can be fully visualized and explained [12].</p>
      <p>One of the principal limitations of this study is the lack of ample training data, which constrains the
performance of the developed ML models. Without a suficiently large and representative dataset, the
models may struggle to generalize findings efectively, potentially leading to biases in classification
outcomes. Moreover, the study indicates the need to explore additional ML approaches beyond the
transformer models used. Techniques from generative AI may also hold promise for improving the
capabilities of citizen contributions analysis, warranting further research into their applicability and
efectiveness [ 35]. The trust of experts and practitioners in these ML models remains a critical issue
that requires further examination. Stakeholders must be assured of the reliability, accuracy, and utility
of ML systems when applied to citizen data. Therefore, ongoing dialogues and workshops should be
conducted to disseminate findings and cultivate confidence in these technologies. Finally, to ensure user
engagement and satisfaction, the design of interfaces built around these ML models should be rigorously
tested and evaluated [34]. Feedback from urban experts, moderators, and decision-makers will be
essential in constructing intuitive and efective analytical tools that foster efective communication
between citizens and policymakers [10].</p>
      <p>Looking ahead, we aim to enhance and retrain our current datasets to improve the predictive
capabilities of our machine learning (ML) models. Ongoing eforts to collect fresh data and refine
existing datasets are essential to ensure that our models remain relevant and efective in responding
to the ever-changing dynamics of urban environments. Future research should also prioritize the
exploration of additional ML models and the implementation of advanced visualization techniques.
These enhancements can increase the interpretability of model outputs, building trust and acceptance
among stakeholders while efectively conveying insights gathered from citizen contributions. Ultimately,
investigating the eficiency potential that ML ofers to governments and companies in e-participation can
provide significant benefits. By automating data analysis and accelerating decision-making processes,
ML models can promote a more collaborative and practical approach to urban planning, ultimately
benefiting both the public and governmental entities.</p>
    </sec>
    <sec id="sec-6">
      <title>6. Conclusion</title>
      <p>In this paper, we examined the RQ " How should textual contributions from citizens be analyzed using
machine learning techniques to classify e-participation data?" The eforts undertaken in this paper
aimed to find the appropriate methods and techniques for combining the technical aspects of modern
ML paradigms with established research on citizen participation.</p>
      <p>After thoroughly examining the relevant research on e-participation, its current implementations,
advantages, and weaknesses, it became clear that scholarly deficiencies exist. Participation facilitators,
decision-makers, and oficial bodies often lacked the necessary tools to process, aggregate, and draw
unbiased conclusions from participation data. The lack of will and resources to conduct meaningful
participation, among other factors, leads to apathy and distrust among the public. The theoretical
ifeld of classical participatory democracy is well-studied, and the barriers to participation are known.
However, the scientific knowledge base to overcome technical barriers that hinder the advancement of
participatory democracy is yet far from suficient. Eforts to facilitate mass participation by creating
adequate IT artifacts are lacking.</p>
      <p>The suggested models can extract the topic, e.g., the class of any contribution from a set of defined
classes, to an impressive degree of accuracy. The presented SVM ensemble can also extract all present
topics in a contribution, thus performing multi-class classification. This gives participants the freedom
to express as many wishes as desired in their contributions, and it allows decision-makers to understand
where the public interest lies, enabling them to create better plans that are satisfactory for most
citizens. However, in addition to the trained ML models and findings about the characteristics of
citizens’ contributions, further research is needed to enhance accuracy and expand existing and publicly
available datasets. Overall, while the results are promising, they underscore the need for further research
to explore the nuances in citizens’ contributions to developing accurate ML classifiers.</p>
    </sec>
    <sec id="sec-7">
      <title>Acknowledgments</title>
      <p>We want to express our sincere gratitude to the Federal Ministry of Education and Research
(Bundesministerium für Bildung und Forschung) for its funding of the RESCUE-MATE project. The project
examines innovative approaches to support citizen participation and civic engagement in urban
planning and emergency management. The funding of RESCUE-MATE, with the grant numbers 13N16835
to 13N16845, enabled us to carry out this research and this paper.</p>
    </sec>
    <sec id="sec-8">
      <title>Declaration on Generative AI</title>
      <p>During the preparation of this work, the author(s) used the GPT-4 mini and GPT 4.1 models from Open
AI to translate texts and to support the writing and development process in Python. Additionally, we
utilize Grammarly for spelling checks. After using these tool(s)/service(s), the author(s) reviewed and
edited the content as needed and take(s) full responsibility for the publication’s content.
International Conference on Advanced Visual Interfaces, Association for Computing Machinery,
New York, NY, USA, 2022, pp. 1–3.
[3] N. Bracarense, R. Bawack, S. Wamba, K. Carillo, Artificial intelligence and sustainability: A
bibliometric analysis and future research directions, Pacific Asia Journal of the Association for
Information Systems 14 (2022).
[4] K. Axelsson, M. Granath, Stakeholders’ stake and relation to smartness in smart city development:
Insights from a swedish city planning project, Government Information Quarterly 35 (2018)
693–702.
[5] S. Philpot, K. Hipel, P. Johnson, Identifying potential conflict in land-use planning using a
valuescentered e-participation tool: A canadian case study in aggregate mining, in: Hawaii International
Conference on System Sciences 2019 (HICSS-52), 2019.
[6] P. Repette, J. Sabatini-Marques, T. Yigitcanlar, D. Sell, E. Costa, The evolution of city-as-a-platform:
Smart urban development governance with collective knowledge-based platform urbanism, Land
10 (2021) 33.
[7] I. Cantador, A. Bellogín, M. Cortés-Cediel, O. Gil, Personalized recommendations in e-participation:
ofline experiments for the “decide madrid” platform, in: Proceedings of the International Workshop
on Recommender Systems for Citizens, Association for Computing Machinery, New York, NY,
USA, 2017, pp. 1–6.
[8] C. Lieven, B. Lüders, D. Kulus, R. Thoneick, Enabling digital co-creation in urban planning and
development, in: A. Zimmermann, R. Howlett, L. Jain (Eds.), Human Centred Intelligent Systems,
Springer, Singapore, 2021, pp. 415–430.
[9] S. Royo, V. Pina, J. Garcia-Rayado, Decide madrid: A critical analysis of an award-winning
e-participation initiative, Sustainability 12 (2020) 1674.
[10] J. Romberg, T. Escher, Making sense of citizens’ input through artificial intelligence: A review
of methods for computational text analysis to support the evaluation of contributions in public
participation, Digital Government: Research and Practice 5 (2024) 3:1–3:30.
[11] D. Bawden, L. Robinson, Information overload: An overview, 2020. Presented at Oxford, June 1,
2020.
[12] M. Borchers, T.-B. Cao, N. Tavanapour, E. Bittner, Designing ai-based systems to support the
analysis of citizens’ inputs from e-participation, in: ECIS 2024 Proceedings, 2024.
[13] O. Maimon, L. Rokach, Introduction to knowledge discovery in databases, in: O. Maimon, L. Rokach
(Eds.), Data Mining and Knowledge Discovery Handbook, Springer US, Boston, MA, 2005, pp.
1–17.
[14] H. Vasudavan, S. Balakrishnan, The taxonomy of smart city core factors, in: Proceedings of the
2019 7th International Conference on Information Technology: IoT and Smart City, Association
for Computing Machinery, New York, NY, USA, 2019, pp. 509–513.
[15] A. Boudjelida, S. Mellouli, J. Lee, Electronic citizens participation: Systematic review, in:
Proceedings of the 9th International Conference on Theory and Practice of Electronic Governance,
Association for Computing Machinery, New York, NY, USA, 2016, pp. 31–39.
[16] M. Hofmann, S. Münster, J. Noennig, A theoretical framework for the evaluation of massive digital
participation systems in urban planning, J geovis spat anal 4 (2020) 3.
[17] B. Stelzle, A. Jannack, J. R. Noennig, Co-design and co-decision: Decision making on collaborative
design platforms 112 (2017) 2435–2444. doi:https://doi.org/10.1016/j.procs.2017.08.
095.
[18] T. Glatz, M. Lippold, Is more information always better? associations among parents’ online
information searching, information overload, and self-eficacy, International Journal of Behavioral
Development 47 (2023) 444–453.
[19] A. Panori, C. Kakderi, N. Komninos, K. Fellnhofer, A. Reid, L. Mora, Smart systems of innovation
for smart places: Challenges in deploying digital platforms for co-creation and data-intelligence,
Land Use Policy 111 (2021) 104631.
[20] P. Toor, K. Olmstead, Skye, Public comments to the federal communications commission about net
neutrality contain many inaccuracies and duplicates, 2017. Last accessed 2024-06-15.
[21] M. Arana-Catania, F.-A. Lier, R. Procter, N. Tkachenko, Y. He, A. Zubiaga, M. Liakata, Citizen
participation and machine learning for a better democracy, Digital Government: Research and
Practice 2 (2021) 27:1–27:22.
[22] J. Romberg, L. Mark, T. Escher, A corpus of german citizen contributions in mobility planning:
Supporting evaluation through multidimensional classification, in: Proceedings of the Thirteenth
Language Resources and Evaluation Conference, European Language Resources Association,
Marseille, France, 2022, pp. 2874–2883.
[23] D. Susar, V. Aquaro, Artificial intelligence: Opportunities and challenges for the public sector, in:
Proceedings of the 12th International Conference on Theory and Practice of Electronic Governance,
Association for Computing Machinery, New York, NY, USA, 2019, pp. 418–426.
[24] M. Cai, Natural language processing for urban research: A systematic review, Heliyon 7 (2021)
e06322.
[25] V. Pitogo, C. Ramos, Social media enabled e-participation: a lexicon-based sentiment analysis
using unsupervised machine learning, in: Proceedings of the 13th International Conference on
Theory and Practice of Electronic Governance, Association for Computing Machinery, New York,
NY, USA, 2020, pp. 518–528.
[26] U. Fayyad, Knowledge discovery in databases: An overview, in: N. Lavrač, S. Džeroski (Eds.),</p>
      <p>Inductive Logic Programming, Springer, Berlin, Heidelberg, 1997, pp. 1–16.
[27] D. Singhal, H. Sirohi, A review on knowledge discovery from databases, 2022. Presented January 1,
2022.
[28] D. Alahakoon, R. Nawaratne, Y. Xu, D. De Silva, U. Sivarajah, B. Gupta, Self-building artificial
intelligence and machine learning to empower big data analytics in smart cities, Information
Systems Frontiers 25 (2023) 221–240.
[29] C. Poudat, H. Lüngen, L. Herzberg, Investigating Wikipedia: Linguistic corpus building, exploration
and analysis, John Benjamins Publishing Company, 2024.
[30] D. Chicco, M. Warrens, G. Jurman, The coeficient of determination r-squared is more informative
than smape, mae, mape, mse and rmse in regression analysis evaluation, PeerJ Comput. Sci. 7
(2021) e623.
[31] M. Alodadi, V. Janeja, Similarity in patient support forums using tf-idf and cosine similarity
metrics, in: 2015 International Conference on Healthcare Informatics, 2015, pp. 521–522.
[32] S. Aljuneidi, W. Heuten, L. Abdenebaoui, M. Wolters, S. Boll, Why the fine, ai? the efect of
explanation level on citizens’ fairness perception of ai-based discretion in public administrations,
in: Proceedings of the CHI Conference on Human Factors in Computing Systems, Association for
Computing Machinery, New York, NY, USA, 2024, pp. 1–18.
[33] N. Bono Rossello, A. Simonofski, A. Castiaux, Artificial intelligence for digital citizen participation:
Design principles for a collective intelligence architecture, Government Information Quarterly 42
(2025) 102020.
[34] M. Borchers, T.-B. Cao, E. Bittner, Toward the ml-based analysis of citizens’ inputs from
eparticipation in urban planning, in: PACIS 2024 Proceedings, 2024.
[35] A. Solatorio, Geoformer: Predicting human mobility using generative pre-trained transformer
(gpt), in: Proceedings of the 1st International Workshop on the Human Mobility Prediction
Challenge, Association for Computing Machinery, New York, NY, USA, 2023, pp. 11–15.</p>
    </sec>
  </body>
  <back>
    <ref-list>
      <ref id="ref1">
        <mixed-citation>
          [1]
          <string-name>
            <given-names>United</given-names>
            <surname>Nations</surname>
          </string-name>
          ,
          <source>World cities report 2022</source>
          ,
          <year>2022</year>
          . URL: https://unhabitat.org/wcr/, last accessed 2024-
          <volume>10</volume>
          -28.
        </mixed-citation>
      </ref>
      <ref id="ref2">
        <mixed-citation>
          [2]
          <string-name>
            <given-names>B. R.</given-names>
            <surname>Barricelli</surname>
          </string-name>
          ,
          <string-name>
            <given-names>G.</given-names>
            <surname>Fischer</surname>
          </string-name>
          ,
          <string-name>
            <given-names>D.</given-names>
            <surname>Fogli</surname>
          </string-name>
          ,
          <string-name>
            <given-names>A.</given-names>
            <surname>Morch</surname>
          </string-name>
          ,
          <string-name>
            <given-names>A.</given-names>
            <surname>Piccinno</surname>
          </string-name>
          ,
          <string-name>
            <given-names>S.</given-names>
            <surname>Valtolina</surname>
          </string-name>
          ,
          <article-title>Copda 2022-cultures of participation in the digital age: Ai for humans or humans for ai?</article-title>
          ,
          <source>in: Proceedings of the 2022</source>
        </mixed-citation>
      </ref>
    </ref-list>
  </back>
</article>