Investigating subjective comfort with aircraft seat via ordinal regression model

In the scientific literature, the debate about how define and evaluate seat comfort is still open, but three points are not in question [1]: 1. comfort is a construct of a subjective nature; 2. comfort is affected by factors of various nature (physical, physiological, psychological); 3.comfort is a reaction to the environment. The subjective nature of the comfort experience is universally recognized; any comfort analysis cannot disregard subjective methods (‘directly asking people about how comfortable they are’), which can be regarded as the most direct way to detect subjective feelings of comfort and/or discomfort. This paper focuses on the assessment of aircraft seating comfort based on subjective comfort responses collected during laboratory experiments. During each experimental session, participants were asked to express their overall seat comfort perception and to evaluate specific seat design features. Comfort responses were analyzed with the aim to relate the perceived overall seat comfort to some design features, as well as to the user anthropometrical characteristics and feelings. The adopted statistical modeling approach is based on generalized linear mixed models. Differently from the traditional strategies used for the analysis of subjective sitting comfort data (e.g. correlation analysis, non-parametric hypothesis tests), the model-based approach allows to investigate and quantify the relationship between overall seat comfort and specific seat/user characteristics. The results show that the overall comfort perception is significantly influenced by age, lumbar support, height of seat pan and reclining.