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  <front>
    <journal-meta />
    <article-meta>
      <title-group>
        <article-title>Predictive Modeling of Instagram User Engagement with tourist photos based on Visual Attributes: The case of Taquile Island - Peru</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>Samantha Ciriaco</string-name>
          <email>samantha.ciriaco@usil.pe</email>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Diana Garayar</string-name>
          <email>diana.garayar@usil.pe</email>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Sandra Sotomayor</string-name>
          <email>sandra.sotomayor@usil.pe</email>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Klinge Villalba</string-name>
          <email>kvillalba@usil.edu.pe</email>
        </contrib>
      </contrib-group>
      <abstract>
        <p>In the tourism sector, photography has evolved from capturing memories to be-coming a tourism digital marketing strategy. The goal of this study is to identify the most important visual attributes that increase Instagram Engagement of the tourist destination Taquile Island (Peru). A predictive model that relates visual attributes and Engagement was developed using 439 photos of Taquile Island extracted from Instagram. These attributes were quantified using Image Analy-sis tools. Neural networks were used for the predictive model construction. This research shows that the most important visual attributes to increase the en-gagement on Instagram are lifestyle and natural landscape.</p>
      </abstract>
      <kwd-group>
        <kwd>1 Predictive model</kwd>
        <kwd>engagement</kwd>
        <kwd>neural networks</kwd>
        <kwd>visual destination image</kwd>
        <kwd>visual content analysis</kwd>
      </kwd-group>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>1. Introduction</title>
    </sec>
    <sec id="sec-2">
      <title>2. Literature Review</title>
      <p>The perception of a tourist destination is not only related to information, but also transmitted through
images; DMOs and DMCs use photos as part of their digital marketing strategy to promote tourist
destinations. As a result, tourists build an image of the tourist destination in their brain (Millet, 2011)
[2], therefore, image plays an important role in tourism (Diez &amp; Crespo, 2020) [3] given that for tourists
who have not visited the destination, it becomes a fundamental reference and a key factor when selecting
a tourist destination which reflects what they expect to see at the tourist destination (Fakeye &amp;
Crompton, 1991) [4]. In the case of tourism, as there is no physical movement of products and services
from where the offer is located to where the demand is found, an effective destination advertising that
provides a good image and encourages the desire to visit the place is very important. Fatanti and
Suyadnya (2015) [5] pointed out that Instagram has developed as a mean of tourist destination
promotion that goes from being a tool for organizations to promote and position tourism destination
brands around the world to spread user-generated content through tourist photos.</p>
      <p>
        There are several attributes in a photo, not all of them can be described as indicators associated with
tourism. Likewise, previous research in tourism has tried to categorize the visual attributes that are
present in a photo (Fahmy et al. 2014) [6]. For example, in the Peruvian context, the visual attributes of
a photo were studied by Stepchenkova and Zhan (2013) [7] in their work Visual destination images of
Peru: Comparative content analysis of DMO and user-generated photography. These researchers
identified ten visual attributes in the photos taken by travelers in the Peruvian territory: (
        <xref ref-type="bibr" rid="ref1">1</xref>
        ) natural
landscape, (
        <xref ref-type="bibr" rid="ref2">2</xref>
        ) people, (
        <xref ref-type="bibr" rid="ref3">3</xref>
        ) archaeological sites, (
        <xref ref-type="bibr" rid="ref4">4</xref>
        ) life style, (5) traditional clothing, (6) architecture, (7)
wild life, (8) adventure, (9) art object, (10) tourist facilities.
      </p>
      <p>Predictive modeling is a process that consists in discovering relationships among data to predict
some desired outcomes in the future using historical data (Mitchell, 2019) [8]. To do so, a set of
predictors or relevant variables are used through the study of both present and historical data (Bhavya
&amp; Pillai, 2020). In the field of Data Science, a sector of the academy has embarked on building models
that can predict the engagement of publications on social networks using different algorithms such as
neural networks (De et al., 2017) [1]
2.1.</p>
    </sec>
    <sec id="sec-3">
      <title>Study Site</title>
      <p>The Southern Route of Peru is one of the most demanded among foreign tourists for including the visit
to Machupicchu. Lake Titicaca, the highest navigable lake in the world, is one of the most important
attractions in this route (MINCETUR, 2020) [9].</p>
      <p>Among the habitable islands in this lake lays Taquile Island, the object of study in this research, that
has 3 essential elements: natural; cultural and human element; which allow to identify and quantify the
largest number of visual attributes.
3</p>
    </sec>
    <sec id="sec-4">
      <title>Materials and Methods 3.1.</title>
    </sec>
    <sec id="sec-5">
      <title>Population Sample</title>
      <p>
        The population of this study consists of the total set of photos of Taquile Island on Instagram which
exceeds 100,000 units. The type of sampling used was non-probabilistic for convenience. Inclusion
criteria consisted of: (
        <xref ref-type="bibr" rid="ref1">1</xref>
        ) photos obtained using the geotag “Taquile Island-Puno” on Instagram; (
        <xref ref-type="bibr" rid="ref2">2</xref>
        ) clear
and non-fragmented photos; (
        <xref ref-type="bibr" rid="ref3">3</xref>
        ) photos of public profiles due to Instagram’s privacy policy; (
        <xref ref-type="bibr" rid="ref4">4</xref>
        ) photos
posted from May 2015 to September 2019; (5) photos of unique posts (with a single photograph). The
sample size included 439 photos, being the most representative sample as compared to similar previous
scientific research.
3.2
      </p>
    </sec>
    <sec id="sec-6">
      <title>Construction of the Model</title>
      <p>For the construction of the predictive model, 17 study variables from different research articles were
defined, and different tools were used to measure such variables. These variables and their
corresponding descriptions are shown in Table 1. Regarding the variable “likes”, Almgren, Lee, and
Kim (2016) [10] found that likes can predict the future popularity of images on social networks. Also,
the variable “awesome” was used by Deng and Li (2018) [11] to create a machine learning-based model
to help DMOs at the moment of selecting photos. The importance of aesthetic characteristics of a
destination is determinant in tourism literature as natural beauty plays a critical role in the destination
choice process (Kirillova, Fu, Lehto, &amp; Cai, 2014) [12]</p>
      <p>The following tools were used:
Downloader for Instagram: Used to download Instagram photos in “.jpeg” format
applying the inclusion criteria detailed in the point 3.1.
•
•
•
•
•</p>
      <p>Google Vision AI: Used to measure the 10 independent variables, proposed by Stepchenkova
and Zhan (2013) [7]. Immediate results were obtained; JSON file was needed to visualize them
completely.</p>
      <p>EyeEm Vision: Used to measure the variable “beauty”.</p>
      <p>
        Everypixel: Used to determine the level in which a photo can be qualified as “awesome”.
SPSS Statistics: The steps followed for the modeling process of the white canvas
were:(
        <xref ref-type="bibr" rid="ref1">1</xref>
        )assigning a type (i.e., dependent or independent variable) in the data of
origin (i.e., dataset) (
        <xref ref-type="bibr" rid="ref2">2</xref>
        ) dividing the data from the model of neural networks into
training and testing data.
3.3
      </p>
    </sec>
    <sec id="sec-7">
      <title>Data Collection and Analysis</title>
      <p>Data collection involved a series of stages. Initially, photographs were obtained by applying the
inclusion criteria explained in “Population and Sample”, using the geotag “Taquile Island-Puno” on
Instagram. Then, data taken by direct observation was registered (e.g., date of publication, date of
collection, followers, likes, comments, user type, presence of text, hashtags). Photos were downloaded
using the Instagram Downloader application, and then they were stored for further analysis with the
instruments of Image Analysis (i.e., Google Vision AI, EyeEm Vision and EveryPixel). This action was
carried out in parallel with data recording. Next, data derived from direct observation and the results of
the analysis with Image Analysis instruments explained in previous steps were consolidated into an
SPSS spreadsheet. Finally, the SPSS Statistics software for automatic analysis of data was used, the
consolidated dataset was imported, and the construction of the prediction model using Neural Networks
was performed, and its accuracy was measured (SPSS output).
4</p>
    </sec>
    <sec id="sec-8">
      <title>Results</title>
      <p>The interrelationships between input nodes (predictor variables), hidden variables (10 of them in two
hidden layers), and the output node (Engagement) are illustrated in Figure 1. The independent variables
(i.e., visual attributes) were combined using two functions: hyperbolic tangent in the two hidden layers
and identity in the output layer.
Fig. 1. Artificial neural network output diagram with insets for each layer. Output figure generated by
IBM SPSS Statistics for Windows, Version 22.0. (Armonk, NY, USA)</p>
      <p>The parameters of the neural network are also shown (Table 3). Regarding the general results of the
neural networks model, it was observed that the model reached an accuracy of 70.20%. (Table 4)</p>
    </sec>
    <sec id="sec-9">
      <title>Discussion</title>
      <p>This study offers several insights into the role of visual attributes present in a photo that enable predicting the
Engagement on Instagram. Now we can find an enormous quantity of visual attributes present on a photo such as
the presence of animals, persons, natural landscape and even the symmetry, balance, contrasts, colours and golden
ratios of the photo are taken into consideration as visual attributes (Thömmes &amp; Hübner, 2018) [18]. Nevertheless,
not all of them are relevant to predict the engagement on Instagram (De, Maity, Goel, Shitole, &amp; Bhattacharya,
2017) [1]. This study fills this gap in tourism literature, by building a ranking of the most important visual attributes
present in a photo of a given tourist destination using neural network which allow DMCs, DMOs and tourism
professionals to elaborate accurate online marketing strategies for tourism destinations on Instagram.</p>
      <p>Visual destination images have been studied in different researches. However, Stepchenkova and Zhan’s
(2013) [7] were the only ones that compared the content-analysis of DMO and user-generated photographs taken
in Peru. They considered that a photo can be fragmented in different visual attributes denominated as categories.
In their study they identified ten main categories associated with photographs taken in Peru. These categories were
identified as a point of reference for the methodology of this study, they were measured using different image
analysis tools. Moreover, a ranking for the most and least important visual image attributes according to different
mathematics techniques was elaborated.</p>
      <p>When a photo is perceived as beautiful, it increases the number of likes and comments on Instagram posts
(Colliander &amp; Marder, 2018) [19]. In this study, we found out that the variable “beauty” has a direct relationship
with the Engagement on Instagram Moreover, Scott et al. (2017) [16] found in their research the importance of
using beautiful photos in tourism marketing to capture tourist attention, using an eye-tracking software and the
Likert-type scale surveys. For this study, the variable “beauty” was also measured using a specialized software
but for image analysis, which means that traditional tools such Likert-type scale surveys - like the one used by
Thömmes and Hübner (2018) [18] to measure the “beauty” of architectural photos - can be replaced with artificial
software for image analyses which contributes to bias reduction or can be used as a complement tool.</p>
      <p>Whereas, Deng and Lin (2018) [11] used the attribute “awesome” as a part of a machine learning model which
enabled DMO to find the right photo for their marketing campaigns. They extracted emotional keywords
comments from UGC, 20,000 photos on Flickr to create this machine learning model. In contrast, in this study the
attribute “awesome” was measured with the tool EveryPixel using instead of words, image analysis.</p>
      <p>Moreover, Belk and Hsiu‐yen Yeh (2011) [20] indicated that the level of human activity has a direct bearing
on the fact that a photograph is captured. However, taking a photograph does not necessarily mean it will be shared
on social media networks. This study suggests that in traditional and rural destinations like Taquile Island, when
a photo shows human activity performed by the local population as a way to show their “lifestyle”, it generates
better reactions (likes and comments) in social media networks.</p>
      <p>Some attributes have a greater impact to predict the Engagement on Instagram than others. Ferwerda, Schedl,
and Tkalcic (2015) [21], Bakhshi, Shamma, and Gilbert (2014) [22] and Araujo, Damilton Correa, Couto Da Silva,
Prates, and Meira (2014) [23], all of them pointed out that the presence of people in a photo generates likes. On
the other hand, the findings of this study revealed that the variable “people” is one of the least important to predict
the Engagement on Instagram.</p>
      <p>Finally, Hausmann et al. (2017) [24] collected geotagged photos from tourists on Instagram to find out what
tourists would particularly like to see or experience when visiting a National Park. They agreed that tourists are
interested in big animals and to experience nature through biodiversity-related activities. However, in this study it
was found out that the variable “wildlife” is not meaningful to predict engagement on Instagram. This can be
explained by the fact that travelers perceived Taquile Island as a rural tourism destination, whereas Kruger
National Park stands out due to its large fauna
5.1</p>
    </sec>
    <sec id="sec-10">
      <title>Conclusions</title>
      <p>This research developed a predictive model which allows us to quantify the visual attributes of tourist
destination photos, as well as to measure the level of Engagement on Instagram combining different
visual attributes. Additionally, in the present research, the most important variables were “number of
followers”, followed by “lifestyle” and “natural landscape”, which are the two most important visual
image attributes to increase the engagement on Instagram. The variable that contributes least is
“awesome”.</p>
      <p>Finally, although the neural network model is more complex than other prediction models it did not
present bias, and it registered a high accuracy (70.20%), which means that through the neural network
model it is feasible to approach the prediction of engagement on Instagram from visual attributes.
5.2</p>
    </sec>
    <sec id="sec-11">
      <title>Theoretical and Practical Implications</title>
      <p>The present research makes a meaningful contribution to the tourism industry literature in relation
to Instagram. First, this study expands the knowledge about destination images regarding the most
important visual attributes of user-generator content (UGC) on Instagram based on a rural destination
in relation to the use of Instagram as a tourism promotion tool. Moreover, this study can be considered
as a point of reference for DMOs, DMCs, tourism marketing professionals or those who want to analyze
photo records in tourism related research, taking advantage that UGC provides credible and
easy-toobtain data for tourism image research (Xiao, Fang, &amp; Lin, 2020) [25] in a context where travelers
themselves freely share photos of their trips on social media. Furthermore, it is useful for them in order
to achieve cost-effective tourism promotions campaigns on Instagram and effective digital marketing
KPIs. It provides insights for DMOs, DMCs and tourism marketing professionals to reduce resources,
increase efficiency at the moment of choosing the right photo according to their needs, select the
appropriate destination marketing strategies and increase the level of engagement on this social network.
The competitiveness of the tourism destination increases with a right tourism image, which improves
the satisfaction and loyalty of tourists (Kim &amp; Stepchenkova, 2015) [26]. In fact, the methodology from
this study can be replicated and/or adapted to other tourism destinations to determine which are the most
important attributes based on the destination characteristics. Also, this methodology can be replicated
in studies of exotic or urban destinations, in order to obtain other types of visual attributes different from
those found on Taquile Island, as a rural destination. Additionally, although there are many studies
based on visual content analysis in the field of tourism, this study is one of the first ones that measures
the visual attributes of a photographics and its influence on Instagram Engagement. This study allows
creating a new approach to tourism promotion using specialized software in a way that allows it to be a
reference for future research and provide valuable insights for tourism professionals.</p>
    </sec>
    <sec id="sec-12">
      <title>5.3 Limitations and Recommendations for future research</title>
      <p>This study makes a significant contribution to tourism literature to understand the Engagement on
Instagram, but it has some limitations. First, in the methodology of this study, a convenience sampling
was used. This does not mean that the results lack validity, but it is necessary to clarify that the model
is significant for the sample analyzed; and it is probably that they should have similarities with a
population-based study.</p>
      <p>Second, the instruments used (e.g., EyeEm Vision, Everypixel) were provided by third parties and
are constantly being updated using algorithms based on the perceptions of professional photographers
so what is considered beautiful or amazing may vary over time. Further, there are people who consider
that computers’ perception of meaning is far from the perception of the human brain. In photographs,
not all the content is literal and an example of this are the “memes”, which are representations with
other meanings that differ from the literal one. In tourism, unstructured data such as the photos shared
by tourists in their social media networks can be quantitatively studied with specialized software.</p>
      <p>This study did not analyze posts in the “carousel” format, it was considered unique posts (a single
photograph), due to the appreciation of users regarding the set of photos it is subjective. In that sense,
metrics such as likes and comments are not precise. For instance, if a user gives a "like" this would not
imply that they like all the photos in a carousel post. Also, it affects the SOR framework proposed by
Mehrabian and Russell (1974) [27] by not being able to break down the photographs individually, and
could not be able to identify and quantify their respective attributes that generated greater engagement
(likes and comments). It should be noted that according to Duangkae (2018) [28] influencers prefer to
publish single posts rather than carousel posts, because single posts obtain a higher average engagement
rate. Moreover, Stine (2020) [29] and Duangkae (2018) [28] pointed out that the engagement generated
by carousel posts goes against nature on Instagram. The reason is that carousel posts consist of many
cards, whereby a user has to swipe right to left to see the other photos. However, Instagram users are
accustomed to swipe up to view the next piece of content.</p>
      <p>Finally, this study intends to explore the visual attributes of a photograph using instruments that can
obtain image patterns, which can hopefully lead to expand this topic in future research, since there are
few similar academic studies related to the tourism sector. Thus, it is recommended to continue using
these tools as well as to replicate the model in other destinations comparable to Taquile Island in order
to identify differences and similarities in the modeling. It is also suggested to keep a record of the
observed and predicted values and to adjust the indicators of the model in order to update its parameters,
since preferences may vary over time. The photographic content is the greatest determinant of
engagement; however, in case that two photos have a similar content, the publication of the one that has
more aesthetics or has the capacity to cause amazement is recommended. This can be controlled with
elements such as effects and color balance, among others. Moreover, this research can be complemented
with qualitative studies with the aim of comparing similarities and differences. Also, for future research,
there is the possibility of building models in which travelers are segmented according to personal
characteristics (e.g., gender, national or foreign origin, etc.).
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