e-Review of Tourism Research (eRTR), Vol. 18, No. 4, 2021 http://ertr.tamu.edu 591 Jan Hruška University of Hradec Králové Josef Zelenka University of Hradec Králové Success factors of airlines' YouTube videos Social media are changing the way that people consume, share, communicate and create content and thus have an important influence on tourism marketing. This paper aims to find which factors are increasing the probability of airlines' videos going viral. The analysis was done on the most successful YouTube airline accounts, which were selected by social media analytical software Socialbakers. IBM SPSS Statistics was used to analyse which factors increase the probability of airline videos going viral. The analysis was done for the ten most successful YouTube airline accounts. A correlation was found between the video length and the number of interactions per 1000 subscribers, and the optimal length of airline video to get the most user interactions. Keywords: YouTube, Airlines, Success factors, Viral Marketing, Social Media Dr. Jan Hruška Ph.D. in Information Technology and Economics University of Hradec Králové Hradec Králové, Czech Republic Phone: +420 724505354 Email: jan.hruska.3@uhk.cz prof. Josef Zelenka Professor at the Department of Recreation and Tourism University of Hradec Králové Hradec Králové, Czech Republic Phone: +420 493332337 Email: josef.zelenka@uhk.cz http://ertr.tamu.edu/ e-Review of Tourism Research (eRTR), Vol. 18, No. 4, 2021 http://ertr.tamu.edu 592 Jan Hruška is an Researcher at University of Hradec Králové. He has a PhD from information and knowledge management. His research interests are Marketing, Management, Tourism, Neural Networks, Machine Learning and Predictions. Josef Zelenka works at the University of Hradec Králové and his lectures and research are focused on carrying capacity, social responsibility in tourism, use of ICT in tourism, marketing of tourism, landscape perception and environmentalism. He is a co-founder and member of the editorial board of the Czech Journal of Tourism, a reviewer of several indexed journals and co-founder of the conference Good Practice in Tourism Sustainability. He also works as an evaluator of scientific projects. His preferred activities are travelling, teaching, sport, and chess. Introduction The Internet and social media have dramatically changed all kinds of areas; digitalization is the new standard, and business models are in constant evolution. Social media are deeply entrenched in our lives. They reached 84 % of the world's internet population aged 15+ and represented the largest portion of individual internet usage, accounting for nearly 1 of every 4 minutes spent online globally (DataReportal, 2020). In keeping with this knowledge, current marketing places increasing emphasis on its practice and gradually on its theory of flexible use of social media (e.g., Ketter, Avraham, 2012). One important issue is increasing the marketing effectiveness of social media content (Musa et al., 2016) intentionally generated by organizations and user-generated content linked to the official accounts of organizations on social media. One measure of this marketing effectiveness may be the degree of virality of the content offered, which is related (in addition to other influences, see mind map in Figure 1) to the nature of the content being offered. The key to successful marketing among social media channels is to create a trust relationship (Wu et al., 2017). Web 2.0 applications can directly engage consumers in the creative process by both producing and distributing information through collaborative writing, content sharing, social http://ertr.tamu.edu/ e-Review of Tourism Research (eRTR), Vol. 18, No. 4, 2021 http://ertr.tamu.edu 593 networking, social bookmarking, and cooperation (Thackeray et al., 2008), including consumers active incorporation in the marketing process (Ketter, Avraham, 2012; in the frame of place marketing). In the context of corporate marketing, Facebook and YouTube occupy a very important position among social media. YouTube, a video-based communication medium, has become one of the most successful ways to express feeling (Safko & Brake, 2010), communicate with friends, and advertise business messages (Ketter, Avraham, 2012). At present, most companies today constantly keep on advertising their products or services and engage with their target customers in social networking sites like Facebook, microblogging websites like Twitter, and video sharing websites like YouTube (Mukherjee, 2019). Airlines have sophisticated digital marketing, and large airlines are active daily on social media (Zelenka & Hruška, 2018b). The most common for them Facebook, Twitter, YouTube, and Instagram, but LinkedIn and some others are also used (Zelenka & Hruška, 2018b). Many airlines even post more than one contribution on Facebook, Twitter, and Instagram a day; on YouTube, that frequency is lower. Perhaps this lower frequency usage of YouTube by airlines is why the marketing of airlines on YouTube is little studied in the literature. That is why the authors decided to develop further the analysis of various aspects of the use of YouTube by airlines and follow up on their previous publications (Zelenka, Hruška, 2018a, 2018b; Pásková, Hruška & Zelenka, 2018). http://ertr.tamu.edu/ e-Review of Tourism Research (eRTR), Vol. 18, No. 4, 2021 http://ertr.tamu.edu 594 Figure 1: Factors, which influence viral potential and popularity of online videos. Source: own elaboration, based on Wang, Yu and Fesenmaier (2002), Ho and Dempsey (2010), Allocca (2011), Camarero and San José (2011), Guadagno et al. (2013). Khan and Vong (2014), Ketelaar et al. (2016), Khan (2017), Chen, Chang and Yeh (2017). Theoretical basis Over the last years, a number of assumptions appear to have risen around social media. The growth of social media has brought a series of obvious changes in how marketing is conducted, most importantly, making it interactive (Deighton & Kornfeld, 2009). Social media alone can have a massive impact when a campaign becomes viral (Macdonald & Wilson, 2012) and are increasingly http://ertr.tamu.edu/ e-Review of Tourism Research (eRTR), Vol. 18, No. 4, 2021 http://ertr.tamu.edu 595 important for brand communication (Murdough, 2009, cit. in Ashley & Tuten, 2014). It is important to keep in mind that this impact can be huge, but it is often also relatively short-term in the case of social media (see viral dynamics in France, Vaghefi, & Zhao, 2016) if other company elements and campaigns do not constantly support it. Allocca (2011) and Khan and Vong (2014) said that to be viral, three things are helpful: 1. tastemakers: many of the famous videos were uploaded even a year before they go viral, but when tastemaker posts it on social media and show it to the greater audience, it speeds up the process, 2. participation; community participates not only by watching the video but also by creating new content from the original video, 3. total unexpectedness; it is necessary to create something that nobody expects. Many studies focused on viral marketing (Wardhana & Pradana 2016, Feroz 2014, Stephen 2016) describe the critical importance of eWOM and customer recommendation. Wardhana and Pradana (2016) mention customer recommendation as to the highest priority. Viral marketing – especially when used as an integrated rather than isolated approach – can improve brand advocacy and increase mass-market brand awareness, all at an infinitely lower cost than conventional media campaigns (Kirby & Marsden, 2006). Several researchers have tried to conceptualize and establish the effects of viral marketing and how consumers as users of social networks develop their attitudes toward viral marketing (Shareef et al., 2017). In the case of videos, the dynamics of their virality are examined in connection with their virality (methodology of dynamics research France, Vaghefi, Zhao, 2016; Sachak-Patwa, Fadai, Van Gorder, 2018 examined this dynamic using http://ertr.tamu.edu/ e-Review of Tourism Research (eRTR), Vol. 18, No. 4, 2021 http://ertr.tamu.edu 596 epidemiological models), and the influences of various factors of their content (e.g., Quesenberry, Coolsen, 2019 examined the effect of embedded stories). As the marketing and communication evolve beyond their traditional forms, graduate marketing pedagogy must evolve to ensure that those charged with the creation of viral marketing campaigns and the management of consumer-generated advertisements understand the factors influencing the success of both (Handelman, 2006; Berthon, Pitt & Campbell, 2008). The notion of building strong and favorable brand associations is regarded as a highly valuable concept in business practice. Understanding and achieving brand value can result in greater loyalty, additional brand extension opportunities, improved perceptions of product performance, marketing success, and sustainable competitive advantage (Keller, 2009). The management of brands is a strategic issue that can affect the firm (Keller, 1999, Payne et al., 2011). Marketers have several options within the social media landscape for branding, including placing paid display advertising, participating in social networks as a brand persona, developing branded engagement opportunities for customer participation within social networks, and publishing branded content (known as content marketing or social publishing) in social channels (Tuten & Solomon, 2013). In connection with the virality of videos, one of the complex factors influencing the virality of these videos on Youtube - their internal factors (length, content, etc.) - was chosen for the research in the case study of airline presentation on Youtube following the authors' previous work (Zelenka, Hruška, 2018a, 2018b; Pásková, Hruška & Zelenka, 2018b). This factor is less studied than the study of viral propagation dynamics (Khan & Vong, 2014; Alhabash et al., 2015; Braun et al., 2017) and the role of influencers and tastemakers (Allocca, 2011; Khan & Vong, 2014), although it is the beginning of a chain influencing the virality of a video on Youtube among many factors (Borges-Tiago, Tiago, Cosme, 2019). At the same time, this study follows a study on http://ertr.tamu.edu/ e-Review of Tourism Research (eRTR), Vol. 18, No. 4, 2021 http://ertr.tamu.edu 597 emotions in Youtube videos (Chen, Chang & Yeh, 2017; Khan, 2017) to determine their effect on the preferences of these videos and a study by Huang, Chen, and Wang (2012), verifying the reasons for sending links on videos on Youtube as a part of the virality of videos. Methods According to the main research topic, which is the virality of airlines videos on YouTube, the following research questions were chosen: 1. What type of videos creates the most interactions in the selected sample? 2. Will people interact more with music or talkative videos in connection to airline companies? 3. What are the optimal settings of videos for the most interactions? Study Design First, the most successful YouTube airline accounts were selected by statistical and social media analytics software Socialbakers, which allows analysis and comparison of Youtube channels. Socialbakers can display daily, monthly or yearly data of interactions, most successful videos, or frequency of uploading new videos. First, airlines were selected using Socialbakers as the top 10 airlines sorted according to the most interactions per 1000 subscribers in one year (from 30.4.2017 to 1.5.2018). Then the top five or six most successful videos (with most interactions, that means most comments, shares, and likes) of every airline company were selected. Videos were analysed according to variables for videos description,.from a sample of 55 videos posted between 30.4.2017 and 1.5.2018. Great attention was paid to the role of music in videos because, as presented by Liikkanen and Salovaara (2015), music videos are the most popular genre on YouTube. As the results of previous studies (Zelenka, Hruska, 2018a, 2018b) pointed to the http://ertr.tamu.edu/ e-Review of Tourism Research (eRTR), Vol. 18, No. 4, 2021 http://ertr.tamu.edu 598 importance of video content, their qualitative analysis was performed. Videos were qualitatively organized into five groups – funny (contains mostly comedy aspects), emotional (expressing strong feelings – sad, regret, lonely, happy), educational, shocking, and others. Data Quantitative Analysis Data and variables for analysis were gathered in different types of statistical and analytical software. Pearson correlation, linear regression, and simple mean analysis were processed in statistical software IBM SPSS Statistics. These statistical correlations were computed between variables total_interactions (total number of all interactions – to like/ dislike the video, and comment on video), interactions_per_1k_subs (number of interactions per 1000 subscribers), length_sec (video length in sec), title_chars (number of characters in the video title), desc_chars (number of characters in the video description), desc_links (number of links in the video description), tag_count (the number of tags/ keywords), music_percent (amount of video filled with music), and cut_number (the number of situations where the camera switched to another screen). Social medial analytical software Socialbakers was used to measure video performance (an activity of subscribers, comments on posts, etc.) in time. The second software for gathering data was vidIQ, a freeware plugin in Google Chrome browser. In vidIQ the VidIQ_SEO_Score was calculated, which is a combination of tag count, tag volume, keywords in the title, keywords in the description, tripled keywords (same keyword used in the title, description, and tags), and ranked tags and high volume ranked tags (both by Google). http://ertr.tamu.edu/ e-Review of Tourism Research (eRTR), Vol. 18, No. 4, 2021 http://ertr.tamu.edu 599 Results The first step in the analysis was to calculate the mean values of all selected variables for all selected videos on YouTube and record minimum and maximum values (Table 1). These values were used to compare in properties of selected videos on YouTube for different airlines. Table 1. The average value of the variables for the selected videos on YouTube Variable Mean Minimum Maximum Interactions_per_1k_subs 32 1,6 471 Length_sec [s] 187 7 1477 Title_chars 46 12 89 Description_chars 470 0 1380 Description_links 3 0 12 VidIQ_SEO_score 24 0 69 Tag_count 14 0 47 Music_percent 52 0 100 Cut_number 92 0 686 http://ertr.tamu.edu/ e-Review of Tourism Research (eRTR), Vol. 18, No. 4, 2021 http://ertr.tamu.edu 600 Table 2. An overview of the interaction and the video length for the selected videos on YouTube Interactions_per_1k_subs Length_sec [s] N of videos Airline Mean value deviation from mean value Mean value deviation from mean value Air France 11 -21 155 -32 5 AirAsia 10 -22 282 +95 6 Emirates 74 +42 120 -67 6 JetBlue 7 -25 90 -97 4 KLM Royal Dutch Airlines 13 -19 171 -16 6 LATAM Airlines 3 -29 652 +465 4 Pegasus Airlines 112 +80 45 -142 6 SpiceJet 17 -15 133 -54 6 Turkish Airlines 37 +5 123 -64 6 WestJet 16 -16 214 +27 6 Total 32 0 187 0 55 The distribution of interactions per 1000 subscribers can be read from Table 2 (interactions_per_1k_subs) and the length of the video for evaluated videos. Airlines highlighted are those with the most interactions (Pegasus Airlines, Emirates, and Turkish Airlines). It is interesting to look at the average length of videos for the most successful airlines: the average video length for the most successful Pegasus Airlines is 45 seconds, and comparable are average video lengths for Emirates (120 seconds) and Turkish Airlines (123 seconds). On the other side, airlines with their average length above 200 seconds have the lowest impression per 1000 subscribers. Therefore, based on that preliminary analysis, the dependence of the number of interactions on video length for selected airlines was graphed (Figure 2). http://ertr.tamu.edu/ e-Review of Tourism Research (eRTR), Vol. 18, No. 4, 2021 http://ertr.tamu.edu 601 Figure 2. Dependence of the number of interactions on the airline's video length The image above (Figure 2) shows how users interact compared to the length of the video in seconds. The following table (Table 3) then shows how users respond to each of the areas airline companies create. Table 3. Type of videos and their interactions per 1000 subscribers for the selected videos on YouTube Type Mean (Interactions per 1000 subs) N (videos) Emotional 17 18 Funny 68 6 Educational 34 26 Others 13 3 Shocking 60 2 Total 32 55 0 20 40 60 80 100 120 0 100 200 300 400 500 600 700 In te ra ct io n s_ p e r_ 1 k_ su b s Lenght_sec [s] http://ertr.tamu.edu/ e-Review of Tourism Research (eRTR), Vol. 18, No. 4, 2021 http://ertr.tamu.edu 602 Qualitative analysis of video content has shown that the most successful airline videos are mostly educational (n=26) and emotional (n=18). From the information shown in Table 4, it can be seen that funny videos with a mean of 68 have the most interactions. The second comparable level is shocking videos, and the third are educational videos. However, this information can be misleading because the sample in the case of shocking (n=2) and funny (n=6) videos is too low and requires verification on a larger research sample. In the selected set of videos, airline companies use a mix of speech and music in their videos in a balanced distribution of 50/50. Correlation between the interactions per 1000 subscribers and the variables music_percent (Pearson Correlation -0,102), length_sec (Pearson Correlation -0,120), title_chars (Pearson Correlation 0,035), desc_chars (Pearson Correlation - 0,158), desc_links (Pearson Correlation -0,182), tag_count (Pearson Correlation -0,205), cut_number (Pearson Correlation -0,106), and VidIQ_SEO_Score (Pearson Correlation -0,089) was tested, and is not statistically significant. The study shows that almost all selected airline companies create short videos (around two minutes long or even less). It is also very common that they are trying to use video descriptions to tell more to the viewer, for example, the story behind the video, promote other websites like social networks, create a call to action elements, or promote their quality service and offers. Discussion Results in Table 2 and Figure 2 shows that the most successful airline companies increase viral potential by creating videos below two minutes long. This inspired the authors in 2019 to do more detailed research on the correlation of video length and number of interactions. For videos of http://ertr.tamu.edu/ e-Review of Tourism Research (eRTR), Vol. 18, No. 4, 2021 http://ertr.tamu.edu 603 selected airlines on YouTube, the interval of video length from 10 sec to 170 sec was chosen, and 100 videos were selected as a sample for the research. The results in Figure 3 show that the maximum number of video interactions is for approximately 70-sec video length. This greatly refined the estimate based on data analysis in Figure 2 and Table 3. At the same time, the dispersion of values confirms the influence of other factors (mind map in Figure 1) and the need to research a larger sample of videos to confirm these conclusions. The effect of the length of the video on the number of views was evaluated on the same sample to find the connection between the length of the video and its success. This analysis confirmed the same trend – shorter videos are being watched more, and there is a significant decrease in the number of views for the video length above 150 sec. However, this dependence is less pronounced in comparison to the number of interactions. Figure 3. Dependence of the number of interactions on the airline's video length. 0 5 10 15 20 25 30 35 40 10 30 50 70 90 110 130 150 170 190 In te ra ct io n s_ p e r_ 1 k_ su b s Lenght_sec [s] http://ertr.tamu.edu/ e-Review of Tourism Research (eRTR), Vol. 18, No. 4, 2021 http://ertr.tamu.edu 604 Airlines are creating the title of the video with 40-50 characters on average. The title should say as much for the potential viewer to inform him what a video is about but at the same time create a certain level of curiosity. It has been shown that the most interesting videos in the case of interactions are videos with the following topics: funny, shocking, and educational. This is in the case of funny and shocking videos in line with the results of Allocca (2011), Nelson-Field, Riebe and Newstead (2013), and Guadagno et al. (2013) that emotions and total unexpectedness (Allocca, 2011) play a vital role in sharing videos. The conclusions regarding recommendations for a higher level of user interaction on YouTube videos are summarized in the diagram in Figure 4. Figure 4. General recommendation for optimal airline video settings. http://ertr.tamu.edu/ e-Review of Tourism Research (eRTR), Vol. 18, No. 4, 2021 http://ertr.tamu.edu 605 Conclusion Except for the results presented in Figure 2 and Figure 3, there has not been proven in the selected sample convincing statistical correlation between the analyzed variables (length of the video in seconds, number of characters in the video title, number of characters in the video description, search engine optimization score by software VidIQ, number of keywords used in the video, amount of music in the video, or number how many times camera switched to another screen) and the interactions per 1000 subscribers. If the selected variables (except video length) have no great impact on the variable interactions per 1000 subscribers, what has the biggest impact on the interactions, people liking, disliking, and commenting on the video? It is the viewer's age, gender nationality, actual feelings, or "individual's integration and relationship with the network and the attitudes towards viral messages" (see model Camarero & San José, 2011)? Countless variables can influence the viral potential, and many articles across the world study it, but it seems that this question is so complex and has not been fully answered yet (see discussion in Wuebben, 2016). Companies and individuals are still learning, and guidelines need updating as frequently as a social media strategy for social media. The level of technology is increasing exponentially. Therefore, it is hard to stay aware of marketing on social media; even social media is changing, new features are being added, more options for marketers and consumers being added, and all of that creates more variables in these viral issues. Further research should focus on the increasing number of successful airline companies on YouTube and their best videos, increasing the number of variables connected to each video, which have some viral potential such as a rate of positive and negative words in videos, colors, and method of distribution to viewers. To perform a detailed analysis in the present study, only the virality and popularity of video factors were analyzed from all the factors listed in the mental map (Figure 1), which is also the http://ertr.tamu.edu/ e-Review of Tourism Research (eRTR), Vol. 18, No. 4, 2021 http://ertr.tamu.edu 606 main limitation of this study. It would be useful to analyze the factors of virality in more detail, as described below, from other points of view as well, and it would be useful to systematically analyze the influence of other factors on the viewership and positivity of YouTube videos. It is advisable to use different methods of video analysis on YouTube - monitoring the history of their use with the analysis of the behaviour of individual users and virality dynamics (Khan & Vong, 2014; Braun et al., 2017), study user's motivations to pass online content (Ho & Dempsey, 2010; Khan, 2017), study the role of influencers and tastemakers (Allocca, 2011; Khan & Vong, 2014), pay more attention to the role of emotion and unexpectedness as a virality factor (Allocca, 2011; Guadagno et al., 2013; Field, Riebe & Newstead, 2013), make more detailed classification of videos by type of emotion (Chen, Chang & Yeh, 2017), and address the dynamics of their virality using the methodology described in France, Vaghefi, and Zhao (2016). Finding the algorithm of videos going viral is a complex problem (France, Vaghefi, & Zhao, 2016). Possible extensions of this work include conducting a similar study for airlines, other tourism services (hospitality, cruises, rent a car), or even other industries (electronics, furniture, etc.). Acknowledgment: This work was supported by the FIM UHK under Grant of Specific Research Project "Information and knowledge management and cognitive science in tourism". The authors wish to express their thanks to Zuzana Kroulíková, a FIM UHK student who assisted with the graphical elements of this study. http://ertr.tamu.edu/ e-Review of Tourism Research (eRTR), Vol. 18, No. 4, 2021 http://ertr.tamu.edu 607 References Alhabash, S., Baek, J-h., Cunningham, C. and Hagerstrom, A. (2015), “To comment or not to comment?: How virality, arousal level, and commenting behavior on YouTube videos affect civic behavioral intentions,” Computers in Human Behavior, Vol. 51, Part A, pp. 520-531, https://doi.org/10.1016/j.chb.2015.05.036. Allocca K. (2011), “Why videos go viral?” TEDYouth 2011. 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