problems being looked at. For example, factors that reduce feelings of crowding within buildings include: Windows – particularly ones that can be opened and ones that provide a view as well as light High ceilings Doors to divide spaces (Baum and Davies) and provide access control Room shape – square rooms feel less crowded than rectangular ones (Dresor) Using partitions to create smaller, personalized spaces within an open plan office or larger work space. Providing increases in cognitive control over aspects of the internal environment, such as ventilation, light, privacy, etc. Conducting a cognitive appraisal of an environment and feelings of crowding in different settings. For example, one might be comfortable with crowding at a concert but not in school corridors. Creating a defensible space (Calhoun) Personal space and territory Proxemics is known as the study of human space. It also studies the effects that population has on human behavior, communication, and social interaction. Having an area of personal territory in a public space, e.g., at the office, is a key feature of many architectural designs. Having such a 'defensible space' can reduce the negative effects of crowding in urban environments. The term, coined by John B. Calhoun in 1947, is the result of multiple environmental experiments conducted on rats. Originally beginning as an experiment to measure how many rats could be accommodated in a given space, it expanded into determining how rats, given the proper food, shelter and bedding would behave under a confined environment. Under these circumstances, the males became aggressive, some exclusively homosexual. Others became pansexual and hypersexual, seeking every chance to mount any rat they encountered. As a result, mating behaviors were upset with an increase in infant mortalities. With parents failing to provide proper nests, thoughtlessly ditching their young and even attacking them, infant mortality rose as high as 96% in certain sections. Calhoun published the results as "Population Density and Social Pathology" in a 1962 edition of Scientific American. Creating barriers and customizing the space are ways of creating personal space, e.g., using pictures of one's family in an office setting. This increases cognitive control as one sees oneself as having control over the competitors to the personal space and therefore able to control the level of density and crowding in the space. Personal space can be both good and bad. It is good when it is used as stated above. Creating "personal space"