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  <front>
    <journal-meta />
    <article-meta>
      <title-group>
        <article-title>Using Sentiment Text Analysis of User Reviews in Social Media for E-Tourism Mobile Recommender Systems</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>Olga Artemenko</string-name>
          <email>olga.hapon@gmail.com</email>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Volodymyr Pasichnyk</string-name>
          <email>vpasichnyk@gmail.com</email>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Nataliia Kunanets</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Khrystyna Shunevych</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <aff id="aff0">
          <label>0</label>
          <institution>Lviv Polytechnic National University</institution>
          ,
          <addr-line>Lviv</addr-line>
          ,
          <country country="UA">Ukraine</country>
        </aff>
        <aff id="aff1">
          <label>1</label>
          <institution>PHEI “Bukovinian University”</institution>
          ,
          <addr-line>Chernivtsi</addr-line>
          ,
          <country country="UA">Ukraine</country>
        </aff>
      </contrib-group>
      <abstract>
        <p>This paper describes main modern tendencies for the design and development of e-tourism recommender systems with sentiment analysis of user generated content in social media. Main goal is to systematize and summarize knowledge about the possibilities of using tourist's user reviews in social media as a type of e-tourism big data for mobile e-tourism recommender systems. In particular, to analyze the sources and types of tourist feedback data, messages and comments generated by the tourist with his gadget that can be related to etourism big data. Developing efficient tools for e-tourism user comments and feedback in social media, combining big data technologies, NLP and smartphone services advantages, can provide e-tourism recommender systems with new better ways of creating more personalized recommendations.</p>
      </abstract>
      <kwd-group>
        <kwd>e-tourism</kwd>
        <kwd>mobile recommender systems</kwd>
        <kwd>trip support</kwd>
        <kwd>content analysis</kwd>
        <kwd>sentiment text analysis</kwd>
      </kwd-group>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>-</title>
      <p>There is an increasing interest for the use of content created by consumers of
hospitality and tourism services, in particular on social networks and video hosting. Thus, the
structure and dynamics of tourists' preferences can be tracked and analyzed,
information about the image and reputation of the tourist product can be received, as well as
about the behavior of tourists themselves when traveling. The feedback received from
the tourist is not only useful for business, but also can be used by recommender
applications as one of the sources for estimation of the alternative item. Two popular
eadvice websites Booking and TripAdvisor host users’ opinions since decades. But they
are very much moderated. Also not every user leaves feedback on tourism-related
review platforms. But every user has a profile in one or more social networks. And there
he publishes different aspects of his life, tourist experience included.</p>
      <p>Copyright © 2020 for this paper by its authors.</p>
      <p>Use permitted under Creative Commons License Attribution 4.0 International (CC BY 4.0).</p>
      <p>
        E-Tourism Recommender Systems
Recommender systems are a class of intelligent information retrieval systems
designed to filter out, in a abundance of information resources, exactly the instances of
data that best meet the interests of a particular user [
        <xref ref-type="bibr" rid="ref1">1</xref>
        ]. Diversified e-tourism
recommender systems are intensively developing and are very popular among the users. But
the problem of getting better, faster, more personalized recommendations is still on
the table. One of the resources for improvements is using tourist’s user reviews and
comments in social media as another kind of recommendation tool.
      </p>
      <p>
        E-tourism recommender systems can be classified according to different
characteristics, such as: architecture, information technology platform, target audience,
methods used for generating recommendations, main tasks to be solved, etc [
        <xref ref-type="bibr" rid="ref2">2</xref>
        ].
      </p>
    </sec>
    <sec id="sec-2">
      <title>E-tourism recommender systems</title>
    </sec>
    <sec id="sec-3">
      <title>Platform</title>
      <p>Knowledge base</p>
    </sec>
    <sec id="sec-4">
      <title>Users</title>
      <p>Methodology
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    </sec>
    <sec id="sec-6">
      <title>Potential</title>
    </sec>
    <sec id="sec-7">
      <title>Ready to go</title>
    </sec>
    <sec id="sec-8">
      <title>With special needs</title>
    </sec>
    <sec id="sec-9">
      <title>Virtual</title>
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The basis for successful operation for mobile e-tourism recommender systems is a
complete, well-timed and correct data processing. There are certain peculiarities in
dealing with input and output data and they should be taken into account when
designing tourist recommender systems, in particular mobile ones. There are three main
sources of input data for a mobile e-tourism recommender system:</p>
      <p>1) The user as an informational source – generates queries, leaves feedback,
disseminates messages about himself on social networks. All smart tourism technologies
nowadays act in the paradigms "tourist as a sensor" and "every tourist is an expert".</p>
      <sec id="sec-9-1">
        <title>Roaming data</title>
        <p>User info profile (including
feedback, reviews and
comments)</p>
      </sec>
      <sec id="sec-9-2">
        <title>Comments and messages from other users</title>
        <p>Bluetooth and other sensors data
2) The gadget of the user itself - information about the external background of the
tourist, contextual data, appearance or disappearance from the operational space of
various obstacles, etc.</p>
        <p>3) Internet content and internet of things - this is data from referential resources,
both tourist and external, work schedules, lists of tourist places and establishments,
public transport timetables, etc., including web search data, user net surfing history
and online booking data, and more.</p>
        <p>user
Internet of things</p>
        <p>Tourist services</p>
      </sec>
      <sec id="sec-9-3">
        <title>Transport services</title>
      </sec>
      <sec id="sec-9-4">
        <title>Other background information</title>
      </sec>
    </sec>
    <sec id="sec-10">
      <title>Meteorological data</title>
      <sec id="sec-10-1">
        <title>Recomendations</title>
        <p>
          The gadget user is a powerful source of information for e-tourism software products.
This data belongs to the e-tourism big data category [
          <xref ref-type="bibr" rid="ref3">3</xref>
          ]. The development of
technology and the phenomenon of social networks have led to the emergence of new
concepts, ways, rules and habits of disseminating information in the digital world.
Hashtag, emoji, geo-positioning, photo and video content, live streams and pages
complemented the classic textual content, which was the main source of tourist
feedback [
          <xref ref-type="bibr" rid="ref4">4</xref>
          ].
        </p>
        <p>
          In particular, the text message that a gatget user leaves as a review of a tourism
product consumed has changed [
          <xref ref-type="bibr" rid="ref5 ref6 ref7 ref8">5-8</xref>
          ].
        </p>
        <p>
          1. The user response has become shorter. First, there are limits to the number of
characters for a single message in different systems, such as Twitter; screen size of
the smartphone – there is an unspoken rule "what wasn’t fit on one screen will not be
read" [
          <xref ref-type="bibr" rid="ref9">9</xref>
          ].
        </p>
        <p>
          2. The space for posting reviews has also changed. Traditionally, users have left
posts on specialized sites, travel forums, travel agency blogs, and more [
          <xref ref-type="bibr" rid="ref10">10</xref>
          ]. To do
this, the user has either logged in or left an anonymous comment. But since the last
decade, a tourist with a gadget leaves a comment anywhere in the social media space
[
          <xref ref-type="bibr" rid="ref11">11</xref>
          ].
        </p>
        <p>
          3. The structure of the comment has also changed: text is now being supplemented
or even partially replaced by graphic, audio and video content. Emoji, stickers,
animated elements convey the emotional tinge of user feedback. Video stories and live
streams may contain text captions and subtitles to increase the content of the response
[
          <xref ref-type="bibr" rid="ref12 ref13">12-14</xref>
          ].
        </p>
        <p>4. The user may not plan and prepare the response text in advance, his story may
be devoted to a completely different topic, and his own impression of the consumed
tourist product will "slip through" among other things. Such reviews are the hardest to
follow, but they also create a reputation for the tourist product [15].</p>
        <p>5. Using a hashtag for text and geo-positioning for images and videos allows you
to uniquely identify the tourism product [16]. Making it easier to find and analyze
data.</p>
        <p>6. Option of personalized feedback from the author of the review. From the official
owner’s profile of the tourist product can be added in response to the tourist post a
gratitude for the positive feedback or an apology in case of complaints [17-18]. In this
way, thanks to the social media space, the product seller is able to reach the
customer's information territory and attract his (and his social environment) attention. It is
also possible to supplement user profile of the recommendation application with new
review facts.</p>
        <p>7. The language used by the tourist: in the forums and official pages of the tourist
objective (classic space for creating reviews), as a rule, one language is used, or in the
case of regional information resources, two: English and the language of the region
[19]. The social media space enables the user to express his or her thoughts in the
language best suited to them [20]. That is, it is likely that the tourism product
provided by one country will have reviews in five, ten or more different languages. Which
complicates the analysis of the text.</p>
        <p>Therefore, travel product reviews need to be collected not only on specialized
resources, but also increasingly in the social media space. Analyzing the sentimental
content of such reviews is complicated, first, by multilingualism and, second, by the
presence of such graphic elements as emoji and stickers. Consumer feedback now
needs to be maintained on users territory – on social media.</p>
        <p>Accordingly, the analysis of the sentimental filling of tourist feedback on tourist
products is not only a source of data for mobile e-tourism recommender systems, but
also transforms from the classic text-mining task to the task of analyzing big data, not
only text [21].</p>
        <p>Finding and retrieving useful information from user reviews of a tourism product
in the social media space poses a number of challenges to developers of recommender
applications. In particular:</p>
        <p>1. How to properly treat sentimental tint of an emoji in reviews? Is negative
content related to the mood of the user, the weather, the day in general or the quality of
the tourist product consumed this day? Is it possible to use for comparison as a
description of previous bad experiences with another product? Should emoji be
considered equivalent to keywords in reviews?</p>
        <p>2. How situational and implicit (no hashtag and location) reviews can be well
tracked and consolidated?
3. How to effectively extract text content from photos, videos and audio messages?
4. Should the publication a tourist photo or video related to the tourist product but
without supplementing the text message be considered as a feedback and how to
classify it: as positive, negative or neutral?</p>
        <p>These and other problems need to be solved to create efficient sentiment analysis
technologies for mobile e-tourism recommender systems.
4</p>
        <p>Using Sentiment Text Analysis for E-Tourism Technologies
Natural Language Processing (NLP) is a field of Computer Science that studies the
use of automatic ways to process natural language. Sentiment text analysis is a fast
growing element of NLP [22]. Automatic processing of e-tourism text data due to the
large amount of content generated by users every minute is becoming more
complicated.
The keys to solve it lie in combining big data technologies, NLP and smartphone
services advantages [23].</p>
        <p>Different domains and types of texts have different information extraction
requirements and thus require different NLP tasks and tools [24]. Developing efficient
tools for sentiment analysis of specific type of text – e-tourism user comments and
feedback in social media can provide e-tourism recommender systems with new better
ways of creating more personalized recommendations.</p>
        <p>There are researches and discussions on the mechanisms behind reviewing tourists
behavior and it’s connection with the data of the reputation sites, hotels, attractions
and destinations have online, and how this affects tourist behavior and purchasing
decisions. Social media feedback data bring new context and new challenges to this
topic. But also they bring new perspectives and resources.
5</p>
        <p>Sentiment Text Analysis of E-Tourism User Reviews
In the first stage, a list of key components of the response was compiled: keywords,
hashtags, emoji, and the order of punctuation was drawn. The keywords were divided
into classes, as well as Ukrainian, English and Romanian, since these three languages
are used by tourists to provide feedback on Bukovina tourist services, as shown in
Tables 1, 2 and 3.
Since Protégé cannot write hashtags via "#", we wrote them using the letter "h". The
hashtags were divided into "Very Positive", "Positive" and "Neutral" as well as being
Ukrainian, English and Romanian as shown in the tables. 4, 5 and. 6.
Дуже позитивні
h_дуже
h_дужесмачно
h_дужевесело
a</p>
        <p>Foarte pozitive
h_foartegustos
h_foartevesel
h_foarteieftin
h_foarte_frumos
h_foarte_tare
h_foarte_amuzant
h_foartefoarte
h_vesel
h_divin
h_perfect
h_perfectazi
h_perfectadimineata
h_perfecta_zi
h_perfectaseara
h_perfecta_dimineat
h_pefecta_seara
h_мандрівки
h_мандрівник
h_мандрівниця
h_мандрівники
h_мандруйдешевше
h_мандруй_сміливо
h_мандруємоукраїною
h_мандрівникиукраїною
h_мандруюукраїною
h_мандриподорожі
h_мандруватилегко
h_мандруй_з_нами
h_мандруй_активно
h_подорож
h_подорожі
h_подорожіукраїною
h_подорожуйукраїною
h_подорожі_україною
h_подорожуємо
h_подорожуйзнами
h_подорожувати
h_подорожуєморазом
h_подорожуй_україною
h_подорожуючиукраїною
Since we can't add emoji to Protégé, we wrote them through the letter "e". Emoji were divided
into "Very Positive," "Positive," "Neutral," "Negative," and "Very Negative." Table 7.</p>
        <p>Emoji
Punctuation marks are used to denote such a dismemberment of a written language
that cannot be transmitted either by morphological means or by the order of the words
in the sentence.</p>
        <p>An exclamation point (!) Is a punctuation mark that is placed at the end of a
sentence to express outrage, a call for strong feelings, anxiety, and more. It can also be
doubled, tripled or used many times to express greater expression and emotionality in
grammatical abuse.</p>
        <p>Question mark (?) Is a punctuation mark, usually placed at the end of a sentence to
express a question or doubt.</p>
        <p>In user reviews, punctuation marks such as question mark (?) And exclamation
mark (!) Are very common, they can be for positive feedback as well as negative
feedback, it all depends on the words found before punctuation marks, positive
keywords or negative .</p>
        <p>Users use punctuation to express or displease tourist services. If after a positive
keyword there are three exclamation marks then the keyword refers to very positive
feedback, but if after a positive keyword there are three question marks then the
keyword refers to very negative feedback. A single exclamation mark after neutral
keywords means that the keyword refers to positive responses, but if one question mark
after a negative keyword means the keyword refers to neutral responses. For example,
a user posted the following comment: Like it! this keyword is not a positive but a very
positive one, because there are three exclamation points after it, or the user left a
"Dear !!!" this keyword refers not to negative but very negative feedback, or the user
left a response: "Why is it so expensive?", the keyword here is "expensive", since
after the keyword one question mark, the response refers to neutral feedback.</p>
        <p>According to the keyword tables, hashtags and emoji built a hierarchy of ontology
classes and subclasses with Protege software. The classes in Protege are displayed as
a class hierarchy (Class Hierarchy). Initially, they created base classes according to
the hierarchy. Instances were created for each class as shown in Figure 4.
The ontology properties were created, corresponding to the areas of definition and
areas of value of the hierarchical ontology. Figure 5.</p>
        <p>Conclusions</p>
        <p>This study is an attempt to systematize and summarize knowledge about the
possibilities of using tourist’s user reviews in social media as a type of e-tourism big data
for mobile e-tourism recommender systems. In particular, to analyze the sources and
types of tourist feedback data, messages and comments generated by the tourist with
his gadget, that can be related to e-tourism big data.
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