Emoji and Self-Identity in T witter Bios (2020)

Abstract: Emoji are widely used to express emotions and concepts on social media, and prior work has shown that users’ choice of emoji reflects the way that they wish to present themselves to the world. Emoji usage is typically studied in the context of posts made by users, and this view has provided important insights into phenomena such as emotional expression and self-representation. In addition to making posts, however, social media platforms like Twitter allow for users to provide a short bio, which is an opportunity to briefly describe their account as a whole. In this work, we focus on the use of emoji in these bio statements. We explore the ways in which users include emoji in these self-descriptions, finding different patterns than those observed around emoji usage in tweets. We examine the relationships between emoji used in bios and the content of users’ tweets, showing that the topics and even the average sentiment of tweets varies for users with different emoji in their bios. Lastly, we confirm that homophily effects exist with respect to the types of emoji that are included in bios of users and their followers.

## introduction with the rise of social media usage and online textbased communication, emoji, a simple but powerfully expressive set of visual characters @xcite , have become a hugely popular means to express emotions, moods, and feelings over computermediated communication @xcite . in the era of big data, with more and more people engaging with social media, researchers have begun to study the ways in which social media users include emoji in their posts, finding that emoji usage is associated with things like personality @xcite , culture @xcite ), * authors contributed equally. and socio-geographical differences @xcite . prior work has typically focused on how people use emoji within the posts that they make online @xcite , or the way that they can be used as reactions to other content @xcite . however, emoji are also commonly used within user's self-created profiles. in this work, we specifically examine the inclusion of emoji in twitter bios, which are short (160 characters maximum) texts describing a twitter account. these bios are featured prominently on a user's profile page, and given their limited length, users often use this space succinctly express the essential information about their accounts. therefore, we expect that the choice of emoji used in these bios will have a strong connection to a user's online self-identity, or the way that they seek to portray themselves to others on a social media platform. the goal of this paper is to give an overview of how emoji are used in twitter bios from a computational linguistics perspective, that is, we treat emoji as a special category of tokens and make use of natural language processing methods to understand the major trends in the ways that people use emoji in their bios and what this says about both the things they tweet about and their follower network. our results provides insights into the variety of ways in which people choose to present themselves online in their twitter bios that may be overlooked when only considering non-emoji word tokens or only considering the ways that people use emoji in the content of tweets. more specifically, we ask, and subsequently describe the work done to answer, the following research questions: rq1. how are emoji used in twitter bios? as a first step, we seek to characterize the ways in which users use emoji in their bios. we look at the types of emoji that most commonly used in twitter bios, and the position within the bios that emoji appear. we compare our findings to trends from the usage of emoji in tweets by the same set of users and note the differences. rq2. what is the relationships between the emoji in a user's bio and the content that the user posts? next, we explore the correlations that exist between the choice of emoji to be included in a user's bio and the content that that user tweets about. we consider this from the perspectives of word-level patterns, topic usage, and overall tweet sentiment. rq3. do users and their followers use emoji in their bios in a similar way? last, we investigate the homophily of emoji usage with bios by studying the follower networks of our core set of users. we look at the similarities in both the absence or presence of emoji in users' bios as well as particular choices of emoji used. ## data for our study, we sampled users from twitter who tweeted between april and july 2020. using the twitter streaming api, we began collecting tweets and storing all user-level information available for as our dataset contains text written in many langauges, we first used the pre-trained fasttext language identification model @xcite to detect the language that each tweet or bio was written in. the most common languages in our datasets were english, japanese, spanish, and portuguese, followed by others. after identifying the langauges, we tokenized the english-language texts using the nltk @xcite tweettokenizer 1 and the texts detected as being written in other languages using the polyglot multilingual tokenizer. 2 4 emoji usage in bios first, we sought to characterize the use of emoji in users' bios, so we turn to just the emojibio dataset. 1 https://www.nltk.org/api/nltk.tokenize.html 2 https://polyglot.readthedocs.io/ group name num. emojis in bios user ratio examples people & body 2485 745 20.0% symbols 301 229 15.4% objects 299 219 15.9% flags 275 215 16.5% travel & places 264 206 14.9% smileys & emotion 162 151 44.3% animals & nature 147 132 18.9% food & drink 131 117 5.5% activities 95 82 15.2% we contrast the most commonly used emoji foot_0 in bios and in tweets in the users who use at least one emoji from each group, we noticed that most users used emoji from the smileys & emotion group in bios, with a total of 44.3% of the 20,000 users, followed by the people & body group with 20% of users including at least one emoji from that group. on the contrary, the number of users who used the emoji of the food & drink group is the least, accounting for only 5% of the total users. this suggests that users choose to represent themselves with more facial expressions, people-centric emoji, and emotions, which are connected to aspects of self-identity. we also found that many users use their bios to present their interests to others -some users use these types of emoji to express their love for certain singers or sports clubs. next, we examine the relationships between sets of emoji that users include in their bios. we selected the top 20 emoji used in bios and computed the mutual information between the presence of these emoji in a user's bio and the presence of any other emoji. the emoji with the highest mutual information scores are presented in and have patterns in the ways that they co-occur with other emoji. another finding is that emoji which are similar to the original emoji have high scores. this finding suggests that similar or the same types of emoji are more likely to be used together. for example, in row 10, four types of ball emoji: basketball ' ', baseball ' ', tennis ' ', and american football ' ', appear in the ten emoji that provide the most mutual information for soccer ball emoji ' '. people who like football may also enjoy other ball sports, and using these ball emoji in the bios at the same time indicates that they are ball sports enthusiasts (either as players or spectators). another example is that in the 14th row, there are eight national flag emoji out of the ten emoji that have the highest mutual information with the american flag emoji ' '. people may use multiple flags in the bios to imply their residences and national origin. finally, we noticed that users tend to use emoji together that fit a specific context. for example, for the ring emoji ' ' in row 18, the most relevant emoji are kiss ' ', person with veil ' ', man in tuxedo ' ', and pregnant woman ' '. people may use these emoji in the bios to express their relationship status, potentially indicating whether they are engaged, married, or expecting a child. we also calculated the mutual information score of non-emoji tokens and the top 20 emoji, as shown in in terms of the quantity of words and hashtags, there are no significant differences between the emojibio and nonemojibio datasets. in the emo-jibio dataset, we noticed that there is increased usage of emoji in bios compared to tweets (3.05 emoji in bios compared to 0.73 in tweets). the fact that the character limit for tweets is more flexible than the limit for bios makes this result even more impressive. in the nonemojibio dataset, the average number of emoji that appear in tweets drops to 0.39, which is roughly half the rate of emoji usage in tweets found in the emojibio group. in terms of hashtags, there is again an increased usage in bios which is similar between the two datasets. in terms of words, users who do not have emoji in their bios tend to use a slightly higher amount of words in their bios and tweets. specifically, the users in the nonemojibio group used roughly 1 more word, on average, than their emojibio counterparts, in both tweets and bios. in addition to differences in the number of words, hashtags, and emoji used, we expect that aspects of a user's identity that are revealed through emoji in their bios will be reflected in measurable ways in the content that they choose to tweet about. we perform a case study in which we select two particular interesting emoji that were common in users' bios, and compare the content of the tweets from users who had these emoji in their bios using both topic modeling and sentiment analysis. the emoji that we focus on for this case study are the rainbow emoji ' ', and the american flag emoji ' '. these emoji are both used with similar frequencies, but are rarely used together and represent distinct groups of users which we seek to understand through the lens of the twitter content that they generate. in our emojibio dataset, the number users using these in bios are close at 324 (' ') and 302 (' '), while only two of the users use both emoji at the same time in their bios, so these two emoji can distinguish users well. these emoji also belong to different emoji subgroups within unicode emoji 13.0: the rainbow ' ' belongs to the sky & weather subgroup under the travel & places group, and the american flag ' ' belongs to the country-flag subgroup under the flags group. among the 324 users who use rainbow emoji ' ', 155 users use english in the bios, 46 japanese, 33 portuguese, and 31 spanish. for comparison, among the 302 users who use the american flag ' ', 245 use english as the language in bios, 15 spanish, 12 japanese, and 9 portuguese. the tweets involved also are multilingual, but are mostly written in english. for the analyses in this section, we first translated all non-english tweets into english using the google translate api. 5 considering that the topic modeling and sentiment analysis methods that we use mostly rely on bag-ofwords representations of the text, issues with the grammatical accuracy of translated tweets will not have as large of an impact. after the translation, we have two sets of tweets corresponding to the two groups of users who used the emoji of ' ' and ' '. the number of tweets for each group are 61,239 and 58,376, respectively. we performed topic modeling using latent dirichlet allocation @xcite on the tweets of users who used the emoji ' ' and ' ' in their bios. we used the coherence score provided by the gensim python library foot_3 to select the number of topics. we train a separate topic model for each group of users, and select four topics for each model. in figure 1 , we visualize the process of inferring topics by zooming in on the most relevant tokens for each of the topics within the set of tweets written by each group of users. the weights between topics are unequal, decreasing from top to bottom as presented in the figure. the topics of tweets from users who use rainbow emoji ' ' in the bios include words related to concepts like life, community, entertainment, and society. we notice some topics that contain more pleasant words, some related to gender identity, others to life and pets. the fourth topic appears to be related to issues of police brutality. however, on the whole, the tweets posted by users who use the american flag emoji ' ' in the bios are more heavy and serious. they are more concerned about topics related to police, president, and current affairs. because of the massive surge in the #blacklivesmatter movement, caused by the death of george floyd in the united states, broke out at the end of may 2020, and we downloaded user tweets during this time, there is a clear topic for this current affair. besides, other current affairs discussed include antifa and covid, but these were part of the same topic. comparing the two sets of different topics, we found that the different emoji included by the users in their bios are related to distinct topics, which also may reflect the self-identities of the users who used these emoji. the rainbow emoji ' ' often represents gay pride, as well as happiness and peace in general, so the corresponding tweets also mostly reflect the love of these users for life and others. in contrast, users who use the american flag ' ' are more concerned about national politics and current affairs within the united states. we also conducted a sentiment analysis on these two sets of tweets, using the vader sentiment analysis tool (hutto and gilbert, 2014), giving the results presented in figure 2 . according to the figure, for the two datasets, the distribution of sentiment is fairly consistent overall, with more positive content than negative. while the amount of neutral sentiment in the two datasets is almost the same, the users with rainbow emoji ' ' in their bios tweeted more positive content overall, compared the the users with the us flag emoji ' ' in their bios. close to 40% of the tweets from users who use rainbow emoji ' ' in bios are positive, and less than 25% are negative. in contrast, less than 35% of tweets sent by users using the american flag ' ' in bios are positive, and close to 30% are negative. these sentiment analysis results are mostly consistent with the results of the topic modeling. the tweets sent by users who use rainbow emoji ' ' are more happy and light than those sent by users who use the american flag emoji ' ' in the bios. this case study suggests that users using different emoji in bios can reflect aspects of both their national identity and their personality. more specifically, this analysis shows that groups using some emoji in the bios generate more positive content than groups using other emoji. ## homophily effects in emoji usage in bios for our final set of analyses, we explored the extent to which users and their followers use emoji in their bios in similar ways. the green heart ' ' and the american flag ' ' are the emoji that are used most frequently by followers of users who also include these emoji. the soccer ball emoji ' ' ranks third, and the dog face emoji ' ' ranks fifth, only with several highfrequency emoji in front of them. there is a strong homophily relationship that indicates that the users use the same emoji with their followers in bios. using the same emoji also reflects that emoji in the bios can reflect the users' self-identity in terms of group belonging, or their social identity. as an illustration, users using dog face emoji in bios may want to signal that they are dog lovers, and they common emoji appearances similar emoji appearances emoji percentage (%) emoji percentage (%) 14.75 34.77 13.72 34.31 13.33 33.91 10.46 33.81 10.4 30.32 in addition to the focused study on these four emoji, we also examined whether the emoji used in bios of twitter users are either the same, or generally similar to those used by their followers in the entire dataset. to assess similarity we trained our own emoji embeddings with a skip-gram model @xcite using the tweets and bios of the emojibio dataset, and subsequently we created a similarity lexicon of emoji based on the cosine similarity between the vectors, considering one emoji to be similar to another if it was within the top ten nearest neighbors in the learned embeddings space. we found that the average percentages for common (i.e., exact matches) and similar emoji appearances between the users of the emo-jibio dataset and their followers are 3.45% and 13.30%, respectively. the respective distributions of the percentage for common and similar emoji appearances are presented in figure 3 . we used permutation tests to confirm that the difference between these two values was statistically significant, and therefore conclude that the followers of a given user seem to have a considerably high probability to use the same, or similar emoji in their bios as the users they follow. ## discussion we now give answers to our original research questions based on our results: rq1. how are emoji used in twitter bios? our results showed that emoji are used in unique ways within users' bios on twitter, even compared to the ways in which they are used in tweets. in general, emoji are positioned earlier in bios than in tweets, while there is a higher percentage of bios that start with an emoji compared to tweets. also, it is more common for an emoji to be the only content of a bio than the only content of a tweet. moreover, facial expression emoji are the dominant type of emoji in tweets, while different variations of heart emoji are dominant in bios. specifically, the most popular emoji in bios are from the smileys & emotion group, while the least frequently used emoji are from the food & drink group. furthermore, we noted that the most frequently used emoji in bios have a high mutual information with other emoji that are similar to them, or from the same category (e.g. hearts, balls, flags), or related to the same concept (e.g. relationship status). in their bios, people tend to use emoji to show their support for musical groups or sports teams (or sports in general), as well as things like countries that they come from or are currently living in. rq2. what is the relationships between the emoji in a user's bio and the content that the user posts? compared to users who do not have any emoji in their bios, users with emoji in their bios use about twice as many emoji in their tweets, on average. they also use less words in both their tweets and bios. in our case study, topic models built from the tweets of the users that use the rainbow ' ' and the american flag ' ' emoji in their bios showed that users who have the rainbow emoji ' ' in their bios tweet about life, community, entertainment, and society, whereas users who have the rainbow emoji ' ' in their bios tweet about police, president, and current affairs. also, it was shown that tweets of users that have the rainbow emoji ' ' in bios convey a more positive sentiment on average compared to users that use the american flag ' ' in their bios. this is just one example to showcase the fact that the types of emoji that people choose to include in their bios reflect larger views, opinions, and sentiments that are expressed in the content of their tweets. rq3. do users and their followers use emoji in their bios in a similar way? the usage of emoji in bios also led us to some conclusions related to homophily effects in twitter. first, our results indicate that followers of users who have emoji in their bios, are more likely to have emoji in their bios as well. we also found that users tend to use the same, or similar emoji in their bios as the users they follow. for example, followers of users with the green heart emoji in their bios also had other colored hearts in their bios, with the green heart being the most common used by the followers. these findings suggest that there are indeed similarities within user networks in the ways in which emoji are used in twitter bios. ## conclusion we have presented an overview of the ways in which twitter users include emoji in their bios, and what kinds of things we can learn about those users from the particular emoji that they use. using a range of approaches, we have shown that emoji are an important component to consider when examining the ways in which users present themselves to others in online settings like twitter. the emoji that users choose to include reveal important aspects of their self-identities, such as the teams and musicians that they support, the activities they enjoy, their national and political identities, and show their similarities with their followers in these same aspects. at the same time, we have only brushed the surface of the types of in-depth analyses that could be performed by consider specific sets of emoji and examining how these relate to the identities of the users who include them in their bios. this work can provide an important complementary view to other work on online-self identity that mainly focuses only on the plain text content. the positioning analysis distribution for bios and tweets is presented in figure 5 . the results of the positioning analysis indicate that emoji appear earlier in bios than in tweets. for each emoji, its positional value was calculated by computing its distance from the first character of the text and dividing it by the overall length of the text. therefore, emoji that were used at the beginning of the text had a positional value of 0, whereas emoji that were used at the end of the text had a positional value of 1.