## 2 Theoretical background
### Research Model  
The study reported in [53] was identified as one of the few works that apply the U&G theory in an online game environment. Based on this work, a research model composed of eight constructs related to hedonic, social and utilitarian gratifications was defined (Figure 2). First, hedonic gratification is captured by: (1) enjoyment (ENJ), (2) fantasy (FAN) and (3) escapism (ESC). Second, it is assumed that (4) social interaction (SINT) and (5) social presence (SPRE) describe social gratification. Finally, (6) achievement (ACH) and (7) self-presentation (SELFP) are proposed as capturing utilitarian gratification. All these constructs in turn influence (8) the continuance intention (CI) to use the Pokemon Go game. Considering this proposal, the present study contributes to an increase the points of view that identify the motivations of the users of Pokemon Go. In fact, the model provides a different perspective when compared with similar studies. For example, [21] analysed the motivations of those continuing to use Pokemon Go, applying the Motives for Online Gaming Questionnaire. In addition, [4] analysed the continued use of Pokemon Go by adopting the Theory of U&G, although the applied model focused on risks and social norms. Finally, [8] analysed the use of Pokemon Go as a tool that drives cognitive performance and emotional intelligence. In a general way, online games are one type of hedonic ICT [23; 53; 56; 57; 58; 59]. Users can alleviate boredom by playing games linked with mobile phones [60]. In this way, enjoyment is considered as a hedonic gratification [61], inasmuch as it is related to activities which are interesting or enjoyable [62]. Indeed, Prior ICT studies identify enjoyment as the main hedonic motivation [63]. In addition, [64] shows that continuance intention is predicted by enjoyment [64; 65; 66; 67]. Based on the above reasoning, enjoyment should exert an influence on continuance intention, and the following hypothesis is posited:  
**Hypothesis 1 (H1)**. : _Enjoyment impacts positively on continuance intention to play the Pokemon Go game._  
Moreover, the ICT literature identifies fantasy as one of the dominant dimensions of video game use [68; 69] and it has been shown to be a strong predictor in determining user behaviour for online communities and gamers using the U&G approach [43; 47; 53; 70; 71]. According to [72] (p. 4), fantasy \"refers to themes that engage users in a creative, imaginative, or even fantasized world of play\". Thus, fantasy could be seen in online games as allowing players to do things that they would not normally be able to do in real life [47; 53; 73], such as building cities or in this case, choosing an avatar with which to catch Pokemon. Hence, in this study, it is expected that fantasy obtained when playing Pokemon Go will increase the continuance intention to play it. Thereby, a hypothesis was established:  
Figure 2: Proposed research model. **Hypothesis 2 (H2). **_Fantasy impacts positively on continuance intention to play the Pokemon Go game._  
Escapism is another hedonic dimension related to the Internet [40, 44, 53] and mobile communications [74]. Augmented reality mobile games allow players to escape by removing themselves from the worries of everyday life [75, 76, 77]. In addition, many authors identified escapism gratification as one of the most consistent predictors of consumption behaviour [78, 79, 80, 81, 82, 83]. Therefore, a hypothesis was suggested:  
**Hypothesis 3 (H3). **_Escapism impacts positively on continuance intention to play the Pokemon Go game._  
Social interaction is a classical gratification in U&G studies [84, 85]. This dimension includes meeting people with similar interests or keeping up with what is going on [86]. In particular, social interaction helps to sustain social gratification for players and relationships with friends [63, 87]. When people socialize, they expect to increase their emotional satisfaction.