ABSTRACT
An important assumption underlying the inclusion of aesthetic factors through visual impact assessment (VIA) systems in the decision-making process is that they will foster more effective, judicious decisions. The ability of any VIA methodology to stand up to such legal tests is strongly related to the methodological properties of reliability, validity, and generalizability. The quality and utility of a measurement method is largely a function of three properties: reliability, validity, and generalizability. Two components of observer-based VIA methods were under examination: the descriptive and evaluative dimensions which serve as the basis for landscape ratings; and the rating procedure. In the context of VIA, reliability represents the degree to which a measure accurately reflects variations among landscape and land use conditions. The chapter describes the development of a landscape classification and the selection of scenes and preparation of visual simulations for use in the psychometric analysis.
