# Analysis of Traffic Organisation in the Kiss-and-Fly Zone of Krakow Airport: Eye-Tracking Study
## 2 Prior Related Works
### Eye-Tracking Technique and Road Signage  
The general motivation for choosing, for assessment and verification, an eye-tracking technique as a method to search and estimate the confusion points and problems of drivers was the following: driving a vehicle by its nature may be attributed to cognitive processes, which is founded mostly on visual input and consequently may be measured by the movements of driver's eyes [4]; this statement could be extended to other types of road users. For instance, when working in the system '_driver-vehicle-road-environment_', proper scanning of the road environment is of the utmost importance and, in case of failure, may be considered a root of the prevalence of accidents [22].  
As it was declared above, the analysis of the K&F zone was focused on its traffic organisation including road signage--road signs and markings--as its key and integral parts. Therefore, it should be pointed out that road signage as well as its elements should be readable and understandable for drivers; at the same time, it must be kept in mind that the detection and comprehension of road signs depends on such factors as the characteristics of road users, environmental conditions and the characteristics of the road signage itself [23]. There are studies confirming problems and differences among drivers when understanding road signs [24; 25]. The same could theoretically be applied to road markings, although appropriate research works were not found.  
Although there is quite a large amount of eye-tracking studies concerning road signs' perception in laboratories [26; 27; 28; 29; 30], eye-tracking field tests focused directly on road signs and markings, which try to solve different issues, are not common. First of all, it should be pointed out the number of studies carried out by one research team, which confirmed that the eye-tracking technique returns valuable outputs when analysing road signs' perception by drivers, which will be discussed below [31; 32; 33]. A systematic review concerning road marking and its influence on drivers' behaviour and road safety mentioned only two studies, which used eye-tracking tools (both carried out in the field) [34]. Additionally, there are research works describing the usage of the same technology to assess the perception of horizontal road marking by drivers ahead of intersections, which also return sensible outcomes [35; 36]. These studies used similar theoretical eye-tracking background and metrics, but all of them were oriented to the general assessment of certain signs without the estimation of traffic organisation itself, although this could be conducted applying the same standard approach.  
Taking into account all the above-mentioned points, it should be repeated that this study is addressed first of all to cover the following research gap: to assess and verify the suitability of eye-tracking tools to search and analyse confusion points, obvious and non-obvious problems and challenges encountered by drivers while performing standard activities in such a complex infrastructure object as the K&F zone as well as their possible reasons. There are also two additional aspects captured by this research work, which could be considered as added values: (1) an assessment on how drivers perceive standardised and unstandardised signage in the K&F zone and (2) a comparison of drivers' behaviour relating to their familiarity with an investigated area. To the best of our knowledge, there is no research work concerning K&F zones conducted from the perspective of drivers' perception; also, this is the first of such a study carried out in Poland. Only standard eye-tracking measures were applied within the scope of this study--the reasons for such a decision will be discussed below.