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  <front>
    <journal-meta>
      <journal-title-group>
        <journal-title>Lviv, Ukraine, November</journal-title>
      </journal-title-group>
    </journal-meta>
    <article-meta>
      <title-group>
        <article-title>Generation of Memes to Engage Audience in Social Media</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>Andrew Kurochkin</string-name>
          <email>kurochkin@ucu.edu.ua</email>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Kostiantyn Bokhan</string-name>
          <email>k.bokhan@whirl.sg</email>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <aff id="aff0">
          <label>0</label>
          <institution>Ukrainian Catholic University, Applied Sciences Faculty</institution>
          ,
          <addr-line>Lviv</addr-line>
          ,
          <country country="UA">Ukraine</country>
        </aff>
        <aff id="aff1">
          <label>1</label>
          <institution>Whirl Software</institution>
          ,
          <addr-line>Kyiv</addr-line>
          ,
          <country country="UA">Ukraine</country>
        </aff>
      </contrib-group>
      <pub-date>
        <year>2019</year>
      </pub-date>
      <volume>1</volume>
      <fpage>5</fpage>
      <lpage>16</lpage>
      <abstract>
        <p>In digital marketing, memes have become an attractive tool for engaging online audience. Memes have an impact on buyers and sellers online behavior and information spreading processes. Thus, the technology of generating memes is a significant tool for social media engagement. The primary purpose of the project is to develop a new approach and compare it to the existing baselines in the field of social media content generation, more precisely - meme generation. A meme is an image superimposed with text, which has humoristic or sarcastic sense; a meme is just another type of visual online content. This project is aimed at applying state of the art Deep Learning techniques as Transformer architecture to the meme generation problem. To achieve project objectives, we are going to collect dataset; create a model for generation of memes and titles based on the input text; create a model for defining optimal time to make a post; measure and analyze system performance in terms of social network audience engagement.</p>
      </abstract>
      <kwd-group>
        <kwd>Meme generation</kwd>
        <kwd>Social network</kwd>
        <kwd>Computational social science</kwd>
        <kwd>Social media interaction</kwd>
        <kwd>Memetics</kwd>
        <kwd>Content generation</kwd>
        <kwd>Reddit</kwd>
      </kwd-group>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>-</title>
      <p>
        Social networks are mass media; they are information hubs. In 2018, digital consumers
spent an average of 2 hours 22 minutes per day on social networks and messaging [
        <xref ref-type="bibr" rid="ref1">1</xref>
        ].
People get information about the news and events from across the world on social
networks every day. Being present on social media is crucially important for an
organization, which provides all kinds of services, products, and information. Organizations put
in great effort to be properly presented in social networks and to run massive
information campaigns.
      </p>
      <p>
        One of the primary purposes of this activity is to engage their audience. Different
kinds and forms of information spread in social networks. Information can be in the
form of text, video, audio or image. Image superimposed with sarcastic or humoristic
text is one of the most common form of the internet meme [
        <xref ref-type="bibr" rid="ref2">2</xref>
        ]. A simple form of the
internet meme is called image macro shown in Fig. 1.
People, who are involved in social media management (SMM), track trending topics
on a regular basis. Keeping an eye on the trends is only part of work; another part is
audience engagement by posting, including meme posts.
      </p>
      <p>To create a meme on the relevant topic, an author of the meme has to come up with
a caption, which will cause emotions in the audience, as well as select the image to
supplement the meme. Once meme has been composed, an author creates a title or
description (it depends on the specifics of a social network). On top of that, when the post
is ready to be published the right choice of the posting time is essential. This whole
process is time-consuming.</p>
      <p>Thus, a solution, which is designed to automate the creation of posts with the image
macro to engage the audience, is important. Even though the solution is limited to
generation of only one type of content, it can be applied to generate other types of internet
memes with some modification.</p>
      <p>
        Engagement is a widely used metric of success for content in social media. Different
actions can be used for the measurement of people engagement and its power [
        <xref ref-type="bibr" rid="ref4">4</xref>
        ]: views,
likes, comments, shares, and reposts. In the scope of this research, we use a number of
comments and score (upvotes - downvotes) to measure engagement. We use Reddit as
the target social network in this research. Our motivation for this choice is introduced
in Section 4.
      </p>
      <p>
        Generation of memes, which engage the audience in the social media, using an image
superimposed with English sentences, can be treated as machine learning in
computational creativity. This set of problems is not investigated as well as classification or
regression tasks. The goal of computational creativity is to model, simulate, or enhance
creativity using computational methods [
        <xref ref-type="bibr" rid="ref5">5</xref>
        ]. Our scientific interest is to investigate how
modern Deep Learning approaches for natural language processing will cope with our
task. In particularly we are going to apply a technique for natural language modeling
Transformer architecture [
        <xref ref-type="bibr" rid="ref6">6</xref>
        ] in solving a creativity problem, which traditionally is a
prerogative of a human.
      </p>
      <p>We are going to create a neural network, which generates memes based on the users’
comments. We use historical data for model training. For modeling of new memes, we
use comments from posts related to news or events, which had not been seen by neural
network (NN) before.</p>
      <p>
        We were faced with a lack of justification to choose evaluation metric to
measurement the humoristic text generated by NN as memes caption. There is no clear answer
which metric to use. Own metrics [
        <xref ref-type="bibr" rid="ref7">7</xref>
        ], BLEU [
        <xref ref-type="bibr" rid="ref8">8</xref>
        ] or perplexity [
        <xref ref-type="bibr" rid="ref9">9</xref>
        ] are used as loss
functions. However, some studies illuminate why one of the most common metric in the
sequence-to-sequence (seq2seq) tasks – BLEU [
        <xref ref-type="bibr" rid="ref10">10</xref>
        ] is a wrong solution in many cases
[
        <xref ref-type="bibr" rid="ref11 ref12 ref13 ref14">11–14</xref>
        ]. Due to this fact, one of the contribution of this work is the experiments to
justify which metric to use for evaluation of humoristic text.
      </p>
      <p>
        The main contributions of the proposed work should be:
1. Create a unique memes dataset based on the Reddit submissions data collected by
pushshift.io [
        <xref ref-type="bibr" rid="ref15">15</xref>
        ]
2. Investigate and justify the choice of the performance metric for the humoristic or
sarcastic text generation
3. Develop a pipeline for memes generation based on the input text using Transformers
architecture
2
      </p>
    </sec>
    <sec id="sec-2">
      <title>Related work</title>
      <p>Our paper relates mainly to three research topics: story generation and image
captioning, meme generation, engagement, and virality in social networks. They are briefly
reviewed in this section.
2.1</p>
      <sec id="sec-2-1">
        <title>Story Generation and Image Captioning</title>
        <p>
          The problem of generating memes caption from input text (comments) can be
approached as a task to produce a short story based on the tags, which set the storyline. In
[
          <xref ref-type="bibr" rid="ref16">16</xref>
          ], the authors approached the problem of hierarchical story generation where the
model first generates a premise and then transforms it into a passage of text [
          <xref ref-type="bibr" rid="ref16">16</xref>
          ].
Researchers used sequence-to-sequence (seq2seq) models [
          <xref ref-type="bibr" rid="ref17">17</xref>
          ] with the usage of a fusion
mechanism [
          <xref ref-type="bibr" rid="ref18">18</xref>
          ], as it had been shown that fusion mechanisms could help seq2seq
models build dependencies between their input and output [
          <xref ref-type="bibr" rid="ref16">16</xref>
          ]. In the scope of this work
an open-source sequence modeling toolkit was used FAIRSEQ [
          <xref ref-type="bibr" rid="ref19">19</xref>
          ].
        </p>
        <p>
          The problem of generating natural language descriptions from the image has been
studied in [
          <xref ref-type="bibr" rid="ref20">20</xref>
          ]. The approach to encode images with Convolutional Neural Network
(CNN) into vector embeddings was proposed. The decoder uses the embeddings to
generate sentences based on the Long-Short Term Memory (LSTM) network. The LSTM
was chosen due to its ability to deal with vanishing and exploding gradients, which are
a common problem in Recurrent Neural Networks (RNN) [
          <xref ref-type="bibr" rid="ref21">21</xref>
          ].
        </p>
        <p>
          In the other work [
          <xref ref-type="bibr" rid="ref22">22</xref>
          ], the authors concentrated on generating captions for images
and videos with different styles. In this work, the authors utilized the FlickrStyle10K
dataset and aimed it at the generation of humoristic or romantic image caption. Here
the model architecture is also based on encoder-decoder design. The solution
architecture was based on the encoder-decoder design with the modifications. The most
valuable of which is the factored LSTM, it automatically distills the style factors in the
monolingual text corpus [
          <xref ref-type="bibr" rid="ref22">22</xref>
          ]. A meme image can be the image with a penguin in the center,
but the main message or subject of the joke can be related to the awkward social
situation [
          <xref ref-type="bibr" rid="ref23">23</xref>
          ]. Since the scene presented in the image can have different meaning than the
whole meme with its cultural background, an image caption does not solve our problem,
as the image is not the right source of information for memes caption.
2.2
        </p>
      </sec>
      <sec id="sec-2-2">
        <title>Meme Generation</title>
        <p>
          The language of Internet memes was modeled in [
          <xref ref-type="bibr" rid="ref8">8</xref>
          ], where an approach which is
common in the economic modeling – copula methods [
          <xref ref-type="bibr" rid="ref24 ref25">24, 25</xref>
          ] – was applied. The authors
claim that the predictive power of copula models could be used for joint modeling of
raw images, text descriptions, and popular votes [
          <xref ref-type="bibr" rid="ref8">8</xref>
          ]. They employed reverse image
search to get text information about the input image.
        </p>
        <p>
          In [
          <xref ref-type="bibr" rid="ref7">7</xref>
          ], the results from [
          <xref ref-type="bibr" rid="ref20">20</xref>
          ] were adopted, however, with ResNet-152 replaced CNN
as a feature extraction method. In this work, authors proposed Funny Score that was
used as a loss function. Funny Score metric is based on the stars from the BoketeDB,
which display the degree of funniness of a caption evaluated by users of the Bokete
[
          <xref ref-type="bibr" rid="ref26">26</xref>
          ].
        </p>
        <p>
          The authors of [
          <xref ref-type="bibr" rid="ref9">9</xref>
          ] based their solution on the approach of [
          <xref ref-type="bibr" rid="ref20">20</xref>
          ]. In order to create
image encoding, the system utilized a pre-trained Inception-v3 network. An important
contribution of the work was a new beam search implementation in order to encourage
diversity in the captions [
          <xref ref-type="bibr" rid="ref9">9</xref>
          ]. For the evaluation, perplexity and human assessment were
used. Images or a combination of image and its name served as input data. The same
image template can have various memes text related to it. Due to this fact, we claim
that memes names have insufficient descriptive power. The authors mention that the
separators between the text at the top and bottom can improve training results.
Therefore, we take into account this observation in our work.
2.3
        </p>
      </sec>
      <sec id="sec-2-3">
        <title>Engagement and Virality in Social Network</title>
        <p>
          In [
          <xref ref-type="bibr" rid="ref4">4</xref>
          ], a 4-level system of engagement classification based on human actions was
proposed: from Level 1 - views, less public and more private expressions of engagement,
Level 2 is like action, Level 3 - comment or share, to Level 4 external posting, the most
public level of engagement. The model for predicting Level 4 engagement was
provided.
        </p>
        <p>
          The study of memes propagation, evolution, and influence across the Web was done
in the [
          <xref ref-type="bibr" rid="ref27">27</xref>
          ]. The authors used a processing pipeline based on perceptual hashing,
clustering techniques, and a dataset of 160M images from 2.6B posts [
          <xref ref-type="bibr" rid="ref27">27</xref>
          ]. The researchers
performed collection of the memes description based on the site Know Your Meme
[
          <xref ref-type="bibr" rid="ref28">28</xref>
          ], which gives information about the memes concepts. This information was used
for the cluster analysis of memes and the creation of their embeddings.
        </p>
        <p>
          In [
          <xref ref-type="bibr" rid="ref29">29</xref>
          ], the authors analyze how post popularity depends on the way the content is
presented (the title), the community it is posted to, whether it has been seen before, and
the time it was posted. The unique contribution of this work is the dataset, which
contains 132K submissions, only 16.7K of which were unique, whereas the others were
resubmissions. These specifics make it possible to determine the influence of the title,
community, and posting time, regarding a submission. In [
          <xref ref-type="bibr" rid="ref29">29</xref>
          ], community and
language models, which help target social media audience, were developed. In this paper,
research focus was on viral content, in the form of republished submissions.
        </p>
        <p>
          In [
          <xref ref-type="bibr" rid="ref30">30</xref>
          ], the phenomenon of image virality was investigated from a computer vision
perspective. Virality score based on the image resubmission was proposed. The neural
network for image virality prediction was created. The results show that in the task of
image virality prediction, based on the high-level image description (capturing
semantic information), a machine performs better than a human. The model shows 68.10%
accuracy relative to 60.12% of human performance.
3
        </p>
      </sec>
    </sec>
    <sec id="sec-3">
      <title>Research Objectives</title>
      <p>
        The main objective of this work is to evaluate how the State-of-the-Art Deep Learning
approaches perform the task of engageable content generation. On top of that, we claim
the following objectives:
1. Even though a few approaches of humoristic text generation were proposed
previously, such as [
        <xref ref-type="bibr" rid="ref31 ref32 ref33 ref34">31–34</xref>
        ], we aim to evaluate a data-driven approach for this task
2. To check whether the neural network trained on the memes which caused
engagement (comments or votes), will be able to produce memes which trigger people
engagement
3. To find out which metric should be used for memes caption evaluation
4
      </p>
    </sec>
    <sec id="sec-4">
      <title>Approach</title>
      <p>In this section, we define the approach to achieve objectives: collection and preparation
of the dataset, model training, plan to choose optimal loss function and overall result
evaluation.
4.1</p>
      <sec id="sec-4-1">
        <title>Dataset</title>
        <p>
          To achieve our objectives, we need a large dataset, which is unavailable. The dataset
must contain unique combinations of meme templates, separated image captions with
top section (also called a set-up) and bottom section (known as punch line), score and
comments. We chose Reddit since, according to the official blog [
          <xref ref-type="bibr" rid="ref35">35</xref>
          ], it has 330 million
of users, 850 000 communities, who generate 58 million votes and 2.8 million
comments daily. It is a common practice in computational social science and social network
analysis to use this platform.
        </p>
        <p>
          Our dataset is based on the data collected by Jason Baumgartner [
          <xref ref-type="bibr" rid="ref15">15</xref>
          ] including all
Reddit posts and comments since 2005. We use 3.5 years of the information,
particularly the timeframe from January 2016 to August 2019. However, our pipeline can be
used to extract information from the whole Reddit dataset since 2005.
        </p>
        <p>
          Source data is split into the batches by months. To use computer storage efficiently,
we are going to process data in batches by erasing all the information irrelevant to our
further research - posts and metadata, which are not related to image macro. Data
collection pipeline includes:
1. Filtering out memes. We extract posts with predefined characteristics from the whole
batch to apply meme information retrieval techniques based on them.
2. Filtering out comments for the posts from the previous step.
3. Downloading images from the posts.
4. Optical character recognition (OCR) to extract top and bottom pieces of text from
the meme. We intend to use Tesseract [
          <xref ref-type="bibr" rid="ref30">30</xref>
          ], which is one of the most common
opensource tools for OCR.
5. Template recognition. We detect which template meme is based on. Each meme will
be presented as an image template id and text extracted in the previous step.
6. Removing the downloaded memes images.
        </p>
        <p>We plan to publish the code of the pipeline and final dataset at a public repository
so these will be parts of our contribution.
4.2</p>
      </sec>
      <sec id="sec-4-2">
        <title>Experiment Pipeline</title>
        <p>
          The key problem in our work is language modeling. Language modeling is usually
framed as unsupervised distribution estimation from a set of examples ( 1,  2, … ,   )
each composed of variable length sequences of symbols ( 1,  2, … ,   ) [
          <xref ref-type="bibr" rid="ref37">37</xref>
          ]. In [
          <xref ref-type="bibr" rid="ref37">37</xref>
          ],
GPT-2 – text generation model based on the Transformer architecture was presented.
This NN shows the State-of- the-Art results on a few datasets without any fine-tuning;
it was trained on a huge variety of Internet texts, including Reddit. Due to this fact, we
use GPT-2 as NN for our approach.
        </p>
        <p>We are going to use GPT-2 355M model as it is more complex than the small 124M,
hence it catches text nature better and is still allows fine-tuning at the machines with
GPU. We are going to do additional training where our dataset of short texts having
specific nature will be used as input.</p>
        <p>To create post titles, we use the same approach as for meme caption, but with a
model pre-trained for title generation. Finally, the image (meme template) that reflects
the idea of the generated text should be chosen. We embed each image in the memes
space based on the encoding of the memes description. We are going to train a neural
network to match the meme caption with the right meme template based on the patterns
that are present in our dataset.</p>
        <p>To define optimal time to make a post we intend to use historical information, once
we achieve that we will use the information to schedule posting.
4.3</p>
      </sec>
      <sec id="sec-4-3">
        <title>Evaluation</title>
        <p>Evaluation includes two phases, first phase - is loss function which estimates the result
of the generated text, second phase is human engagement measurement.</p>
        <p>Even though the absolute value of the loss function could not be treated as a clear
metric of how good the result is, it gives the model a tool to estimate the quality of the
results. It is important to choose the right sense of humor for the neural network so it
can better distinguish good memes from bad ones. We are going to train a few models
based on different loss functions and generate a batch of 50 images from each of them.
Estimating the quality of humor is impossible, as it is a very subjective matter. In this
work, we are bounded to our target audience, so we are going to ask the English
speaking audience which memes they prefer more. The loss function from the model, which
outperformed the other models, will be used for the final model training.</p>
        <p>The second part is the engagement measurement, which is the key metric in our
problem. Proposed evaluation pipeline is depicted in Fig. 2. The essence of the
evaluation process is to measure user interaction with the content. Metrics of engagement will
be the number of comments and post overall score, which are statistics to measure the
power of people engagement.
5
5.1</p>
      </sec>
    </sec>
    <sec id="sec-5">
      <title>Research Plan</title>
      <sec id="sec-5-1">
        <title>Dataset Collection</title>
        <p>It takes weeks to process our input data to build the dataset. To minimize risks of failure,
we have found a limited dataset, which can be used in our project to check the claimed
hypothesis and answer the stated research questions. We intend to finish data
preprocessing by the end of October.
5.2</p>
      </sec>
      <sec id="sec-5-2">
        <title>Pipeline</title>
        <p>We plan to use the Transformer architecture, GPT-2 model with minor modifications
to adopt it to specifics of our problem. This task should be done while the data
collection pipeline is working on the clusters.</p>
        <p>
          During the first iteration, the models using different loss functions should be trained.
At the time when the outcome of the model will be acceptable from our point of view,
they will be evaluated with using independent experts (crowdsourcing service, Amazon
Mturk [
          <xref ref-type="bibr" rid="ref38">38</xref>
          ]). The loss function, which yields the best results based on people opinions,
will be used for future iterations.
During the model training process, we are going to build pipelines for posting on social
networks and for feedback collection. We plan to finish this by the middle of
November.
5.4
        </p>
      </sec>
      <sec id="sec-5-3">
        <title>Pipeline Revision and Refinement</title>
        <p>The pipelines used in this project are strongly dependent on a bunch of the third party
applications. This is an additional risk factor, so we have planned some time to resolve
potential issues. When the right metric has been found, the model training pipeline
should be refined.
5.5</p>
      </sec>
      <sec id="sec-5-4">
        <title>Supporting Activity</title>
        <p>We use agile with weekly sprints, so we can fix all the problems and tasks in the week
log. We store all ideas, hypothesis, and insights in the experiments documentation. All
these materials will be used as a basis for the thesis manuscript.</p>
      </sec>
    </sec>
    <sec id="sec-6">
      <title>Conclusion</title>
      <p>The considered problem is relatively new, and it involves different disciplines and
scientific areas. There have been studies on the engagement analyses, social media
influence, modeling of information spreading, even memes generation already have been
done, however, the combination of factors which we set as the project objectives makes
this work unique.</p>
      <p>The result of this project will be evaluation of the current progress of Deep Learning
in natural language modelling. It will show how it performs for content generation task.
In the future, it can be used as a base for generating more complex scenes. In the scope
of the project, we aim to find a metric, which properly captures the specific nature of
the memes captions based on human opinions. This knowledge is a part of our
contribution as well as unique memes dataset.</p>
      <p>We described motivation and importance of approaching meme generation problem,
made an overview of works, which are related to the current study from different sides,
defined clear and achievable project objectives, proposed an approach to achieve stated
goals and briefly described plan of the project work.</p>
    </sec>
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