In order to assess outdoor comfort of individuals, this paper discusses the results of an expanded non-linear model using Box-Cox transformation. Instead of thermal sensation, individuals’ comfort assessment was used as the dependent variable. Further, a flexible non-linear model that allows for decreasing or increasing marginal effects of the explanatory variables on the ratings of outdoor comfort was specified. Apart from the physical microclimatic and environmental attributes, the variables related to the socio-demographics, emotional status, expectations, preference, perceptions and behavioral aspects were also incorporated in the model. To reduce the potential dependency of results on the sampled locations, a stated choice experiment was designed to systematically vary the conditions with different combinations of spatial attributes. The data was collected through a structured questionnaire and physical measurements of the surrounding environment from eight public spaces in Eindhoven, The Netherlands. Results show that the influence of non-physical factors, such as socio-demographics, behavioral and psychological attributes, on outdoor comfort are substantial and significant.