Cox et al. in 2006 (Cox, 2006) concluded that the perception of crowding in passenger rail is created from an "interplay of cognitive, social and environmental factors, whereas density refers to objective physical characteristics of the situation ". Likewise, there is sufficient literature available establishing the fact that crowding depends not only on physical density but also on various physical backgrounds, interpersonal factors, individual characteristics, and modifiers (Sundstorm, 1978). Culture also plays a role in the perception or tolerance of crowding. Evans et al. (2000) found that residential overcrowding has a negative effect in terms of psychological distress in different cultures; Mexican and Vietnamese Americans perceive their homes as less crowded (based on a given number of people per room) compared to African Americans or Anglo Americans (Zheng Li, 2013). In 2006, Cox et al. developed a theoretical model that describes the relationship between overcrowding and its impact on health. The figure below shows this model. Figure 5- Relationship between overcrowding and health (Source: (Cox, 2006)(Zheng Li, 2013)) “In Australia, researchers Hirsch and Thompson (2011) identified eight factors that can influence the perception of rail congestion: (1) expectations based on previous travel experiences. (2) The environment, which includes weather conditions (for example, perceived crowding would be excessive in the event of rain) and transportation, such as the quality of the air conditioning system, air circulation inside the wagon, the presence and design of handles for standing passengers. , the layout and arrangement of seats, the cleanliness of the car. (3) Communication – poor quality of information provided... middle of document ......t stress and feelings of exhaustion; and (3) Assessments of psychosocial aspects of the crowded situation and its surrounding environment as well as passenger density do not directly predict stress and feelings of exhaustion (Zheng Li, 2013). Regularly capturing subjective perceptions of overpopulation can be a tedious and expensive exercise. Thus, it can be used as a means of identifying discrepancies between objective standards and subjective public perceptions. Additionally, it can be used to identify the cost of overcrowding using the estimation of users' willingness to pay for a less congested and more comfortable public transport system. The economic method used to calculate and value encumbrance is known as the contingent valuation method, which has its roots in environmental economics and the valuation of non-market goods. It is discussed in detail in the following section.