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  <front>
    <journal-meta>
      <journal-title-group>
        <journal-title>M. Spano);</journal-title>
      </journal-title-group>
    </journal-meta>
    <article-meta>
      <title-group>
        <article-title>TAll: a new Shiny app of Text Analysis for All</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>Massimo Aria</string-name>
          <email>massimo.aria@unina.it</email>
          <xref ref-type="aff" rid="aff0">0</xref>
          <xref ref-type="aff" rid="aff3">3</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Corrado Cuccurullo</string-name>
          <email>corrado.cuccurullo@unicampania.it</email>
          <xref ref-type="aff" rid="aff0">0</xref>
          <xref ref-type="aff" rid="aff2">2</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Luca D'Aniello</string-name>
          <email>luca.daniello@unina.it</email>
          <xref ref-type="aff" rid="aff0">0</xref>
          <xref ref-type="aff" rid="aff3">3</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Michelangelo Misuraca</string-name>
          <email>michelangelo.misuraca@unical.it</email>
          <xref ref-type="aff" rid="aff0">0</xref>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Maria Spano</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
          <xref ref-type="aff" rid="aff3">3</xref>
        </contrib>
        <aff id="aff0">
          <label>0</label>
          <institution>K-Synth spin-off, University of Naples Federico II</institution>
          ,
          <addr-line>80126 Napoli</addr-line>
          ,
          <country country="IT">Italy</country>
        </aff>
        <aff id="aff1">
          <label>1</label>
          <institution>University of Calabria</institution>
          ,
          <addr-line>87036 Arcavacata di Rende (CS)</addr-line>
          ,
          <country country="IT">Italy</country>
        </aff>
        <aff id="aff2">
          <label>2</label>
          <institution>University of Campania “Luigi Vanvitelli”</institution>
          ,
          <addr-line>81043 Capua (CE)</addr-line>
          ,
          <country country="IT">Italy</country>
        </aff>
        <aff id="aff3">
          <label>3</label>
          <institution>University of Naples Federico II</institution>
          ,
          <addr-line>80126 Napoli</addr-line>
          ,
          <country country="IT">Italy</country>
        </aff>
      </contrib-group>
      <pub-date>
        <year>2023</year>
      </pub-date>
      <volume>000</volume>
      <fpage>0</fpage>
      <lpage>0002</lpage>
      <abstract>
        <p>The rapid technological advancements in recent years allowed to process different kinds of data to study several real-world phenomena. Within this context, textual data has emerged as a crucial resource in numerous research domains, opening avenues for new research questions and insights. However, many researchers lack the necessary programming skills to effectively analyze textual data, creating a demand for user-friendly text analysis tools. While languages such as R and python provide powerful capabilities, researchers often face constraints in terms of time and resources required to become proficient in these languages. This paper introduces TAll - Text Analysis for All, an R Shiny app that includes a wide set of methodologies specifically tailored for various text analysis tasks. It aims to address the needs of researchers without extensive programming skills, providing a versatile and general-purpose tool for analyzing textual data. With TAll, researchers can leverage a wide range of text analysis techniques without the burden of extensive programming knowledge, enabling them to extract valuable insights from textual data in a more efficient and accessible manner.</p>
      </abstract>
      <kwd-group>
        <kwd>text analysis</kwd>
        <kwd>shiny app</kwd>
        <kwd>web app1</kwd>
      </kwd-group>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>1. Introduction</title>
      <p>In the era of big data, researchers across various
disciplines are increasingly faced with the challenge of
analyzing vast amounts of textual data.</p>
      <p>Textual data, such as research articles, social media
posts, customer reviews, and survey responses, hold
valuable insights that can contribute to the
advancement of knowledge in fields ranging from
social sciences to healthcare and beyond.</p>
      <p>Researchers seek to analyze textual data to
uncover patterns, identify trends, extract meaningful
information, and gain deeper insights into various
phenomena. By employing advanced natural language
processing (NLP) techniques and machine learning
algorithms, researchers can explore the semantic and
syntactic structures of texts, perform topic detection,
polarity detection, and text summarization among
other analyses. Moreover, the advent of digital
platforms and the proliferation of online content have
generated vast amounts of textual data that were
previously inaccessible or challenging to obtain.</p>
      <p>This paper presents the first version of TAll - Text
analysis for All - a new R Shiny app that brings
together all the major advancements in text analysis
developed in recent years. For researchers who lack
programming skills, TAll offers a viable solution,
providing an intuitive interface that allow researchers
to interact with data and perform analyses without the
need for extensive programming knowledge.</p>
      <p>TAll offers a comprehensive workflow for data
cleaning, pre-processing, statistical analysis, and
visualization of textual data, by combining
state-ofthe-art text analysis techniques into an R Shiny app.
2. Discovering TAll workflow</p>
      <p>First TAll combines the functionality of a set of R
packages developed for NLP tasks (see:
https://cran.rproject.org/web/views/NaturalLanguageProcessing.
html) with the ease of use of web apps using the Shiny
package environment. TAll workflow aims to facilitate
the discovery and analysis of text data by
systematically processing and exploring the content.</p>
      <p>Figure 1 shows the three main steps of a TAll
workflow.
annotation process (i.e., tokenization, PoS tagging, and
lemmatization).</p>
      <p>TAll utilizes pre-trained models provided by Universal
Dependencies Treebanks. Universal Dependencies
(https://universaldependencies.org) is a framework
for consistent annotation of grammar (Part-of-Speech,
morphological features, and syntactic dependencies)
across different human languages. UD is an open
community effort with over 500 contributors
producing over 200 treebanks in over 100 languages.
By using these models TAll supports the analysis of
texts written in 60 different languages.</p>
      <p>Each text is parsed into individual tokens (words) and
tagged with its respective Part-of-Speech (PoS) label to
better understand word usage patterns. All the
subsequent statistical analyses could be performed
alternatively on tokens or lemmas. Moreover, users
can define and load custom lists of words for various
research purposes (e.g., to substitute synonyms,
remove domain stopwords, and semantically tag</p>
      <p>The first step Import and Manipulation involves
importing one or multiple text files in various formats,
such as txt, csv, xlsx, and pdf, allowing easy loading of
a diverse range of textual data. Subsequently, texts
could be subjected to several editing actions, including
the division into smaller segments, such as chapters or
paragraphs, or the selection of texts' subsets for
sampling or random analysis purposes. Users can
supplement the imported texts with additional
external information (e.g., author, publication date,
rating) attached to the texts or added during the
analysis. Concerning both the aim of analysis and the
availability of external variables, texts could be
filtered, enabling to focus on specific subsets or
grouped for comparison purposes.</p>
      <p>Before beginning the Pre-processing and
Cleaning step, a language model was necessary for the
specialized lexicons'terms).</p>
      <p>
        A crucial aspect when we deal with text analysis is
to identify and handle multi-word expressions and
collocations. To face this issue, TAll performs Rapid
Automatic Keyword Extraction (RAKE) algorithm [
        <xref ref-type="bibr" rid="ref1">1</xref>
        ]
that uses a delimiter-based approach to identify
candidate keywords and scores them using word
cooccurrences that appear in the candidate keywords.
At the end of pre-processing and cleaning phase, users
can select specific PoS tags to focus their analyses
considering only content-bearing words (e.g., nouns,
adjectives, verbs, collocations).
      </p>
      <p>Statistical analysis and Visualization step opens
the opportunity of exploring cleaned texts by
performing one or more approaches as listed in Figure
1. Descriptive statistics (e.g., number of tokens, types,
sentences, lexical measures), word frequency
distribution, and wordclouds provide an initial
overview of the text corpus. TAll tabs are then
organized by considering two levels of analysis: words
and documents.
•
•
•
•
•
•
The documents tab includes a set of statistical methods
to cope with specific tasks where the focus is properly
on the entire documents:</p>
      <sec id="sec-1-1">
        <title>Topic Modeling to identify both prominent</title>
        <p>
          topics and their distribution within
documents using the well-known Latent
Dirichlet Allocation (LDA) algorithm [
          <xref ref-type="bibr" rid="ref11">11</xref>
          ].
Moreover, TAll estimates the number of
topics automatically through the measures
proposed in [
          <xref ref-type="bibr" rid="ref12 ref13 ref14 ref15">12, 13, 14, 15</xref>
          ], but users can
also explore different solutions by setting the
number of the desired topics;
Polarity Detection to determine the polarity
(positive, negative, neutral) of documents by
choosing among different lexicons (i.e., Hu &amp;
Liu [
          <xref ref-type="bibr" rid="ref16">16</xref>
          ], Loughran &amp; McDonald [
          <xref ref-type="bibr" rid="ref17">17</xref>
          ], nrc
[
          <xref ref-type="bibr" rid="ref18">18</xref>
          ]);
Summarization to concisely summarize each
text to capture key insights rapidly. TAll
performs TextRank algorithm [
          <xref ref-type="bibr" rid="ref19">19</xref>
          ], based on
applying Google’s PageRank [
          <xref ref-type="bibr" rid="ref20">20</xref>
          ] to the
network of sentences for extracting the most
relevant ones.
        </p>
        <p>This comprehensive workflow provides users with
the statistical methods to process texts efficiently and
share their results and workflows with collaborators
by downloading plots and reports from TAll,
facilitating and speeding up all analysis steps.
paragraph in every section does not have first-line
indent. Use only styles embedded in the document.</p>
      </sec>
    </sec>
    <sec id="sec-2">
      <title>3. Conclusion and remarks</title>
      <p>
        Detailed analysis of words includes a set of
statistical methods mainly devoted to topic detection.
The most intuitive approach is to identify and visualize
through dynamic plots the most frequently used words
for each PoS tag, looking obviously at their absolute
frequency but also considering more complex
weighting schemes as term frequency/inverse
document frequency (TF-IDF) [
        <xref ref-type="bibr" rid="ref2">2</xref>
        ] to uncover words
with the highest discriminative power. Despite the
simplicity, often analyzing the frequency distribution
of words gives a general idea of the contents in the text
collection, but it is not enough to identify topics. A
topic can be represented as a set of meaningful words
with syntagmatic relatedness [
        <xref ref-type="bibr" rid="ref3">3</xref>
        ].
      </p>
      <p>
        Following this definition, the three methods most
widely shared in the literature [
        <xref ref-type="bibr" rid="ref4">4</xref>
        ] are implemented in
TAll:
      </p>
      <sec id="sec-2-1">
        <title>Clustering [5, 6] to group similar words based</title>
        <p>
          on their usage patterns or context;
Correspondence Analysis [
          <xref ref-type="bibr" rid="ref7 ref8">7, 8</xref>
          ] to explore
semantic relationships among words,
identifying the latent structure of the text
collection;
Network (Co-word analysis and Grako) [
          <xref ref-type="bibr" rid="ref9">9</xref>
          ] to
analyze co-occurrence patterns of words
within texts, highlighting subsets of words
strictly related through community detection
algorithms [
          <xref ref-type="bibr" rid="ref10">10</xref>
          ].
        </p>
        <p>This paper presented a brief overview of the first
version of TAll, a new shiny app for importing,
preprocessing, and analyzing textual data.</p>
        <p>Our idea stems from the now growing need to analyze
textual content to today's ever-increasing number,
offering the opportunity to explore it quickly and
efficiently, even for those without programming skills.
Using a user-friendly text analysis tool, researchers
can focus more on their domain expertise and research
questions rather than spend significant time learning
programming languages or writing complex code.
Tools like TAll democratize text analysis, making it
accessible to a broader audience and promoting
interdisciplinary collaboration.</p>
        <p>Moreover, general-purpose software can be used in
every research field and encourages reproducibility
and transparency in research. paragraph in every
section does not have first-line indent. Use only styles
embedded in the document.</p>
      </sec>
    </sec>
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