# Eye Tracking and Human Influence Factors' Impact on Quality of Experience of Mobile Gaming
###### Abstract  
Mobile gaming accounts for more than 50% of global online gaming revenue, surpassing console and browser-based gaming. The success of mobile gaming titles depends on optimizing applications for the specific hardware constraints of mobile devices, such as smaller displays and lower computational power, to maximize battery life. Additionally, these applications must dynamically adapt to the variations in network speed inherent in mobile environments. Ultimately, user engagement and satisfaction are critical, necessitating a favorable comparison to browser and console-based gaming experiences. While Quality of Experience (QoE) subjective evaluations through user surveys are the most reliable method for assessing user perception, various factors, termed influence factors (IFs), can affect user ratings of stimulus quality. This study examines human influence factors in mobile gaming, specifically analyzing the impact of user delight towards displayed content and the effect of gaze tracking. Using Pupil Core eye-tracking hardware, we captured user interactions with mobile devices and measured visual attention. Video stimuli from eight popular games were selected, with resolutions of 720p and 1080p and frame rates of 30 and 60 fps. Our results indicate a statistically significant impact of user delight on the MOS for most video stimuli across all games. Additionally, a trend favoring higher frame rates over screen resolution emerged in user ratings. These findings underscore the significance of optimizing mobile gaming experiences by incorporating models that estimate human influence factors to enhance user satisfaction and engagement. g 2024 16 420 10.390/616110420 10.  
quality. However, many factors can influence user ratings regarding the quality of the stimuli, ranging from human to context, etc. The term influence factor (IF) is defined as _'Any characteristic of a user, system, service, application, or context whose actual state or setting may have influence on the Quality of Experience for the user'_[8; 9]. The Mean Opinion Score (MOS), as defined by the International Telecommunication Union Standardization Sector (ITU-T) [10], was originally developed to gauge user opinions on speech quality in telecommunications. However, it has become a de facto standard due to its extensive applicability across various multimedia applications. The effectiveness of the MOS for evaluating video stimuli has been questioned in numerous studies, particularly regarding whether the distinction between \"excellent\" and \"good\" is equivalent to that between \"fair\" and \"poor\" [11; 12]. To address these concerns, alternative metrics such as %Good or Better (GoB) and %Poor or Worse (PoW) have been proposed to provide a more transparent and meaningful interpretation of user feedback [13; 14]. The objective of this article is to examine the human influence factors in mobile gaming. Specifically, we analyze the impact of user delight (liking) towards displayed content and the effect of gaze tracking on mobile gaming. Previous studies on multimedia streaming stimuli have explored various influence factors such as delight, mood, gender, and frequency of watching online videos, etc., establishing the role of delight in the user ratings [15; 16; 17; 18]. Our observations revealed that user delight towards the displayed content affects the MOS for certain stimuli, though the results were not statistically significant across the entire dataset [19; 20]. A notable finding was that the nature of content significantly influences the MOS, particularly when the same videos with minor impairments are repeatedly shown due to packet loss or jitter degradation. At high jitter levels and packet loss exceeding 1%, MOS values predominantly fell into the poor or worst range, rendering meaningful interpretation difficult.