Understanding competing web application platforms : An extended theory of planned behavior and its relative model

Despite many competing software systems being offered by different vendors, studies in information technology (IT) adoption rarely look at the adoption of competing products. We develop an extended theory of planned behavior (TPB), drawn from social psychology and marketing theories, to predict choice intention and subsequently the choice of two products. The extended TPB is used to compare the two products in a single analysis using relative values. The study is set in the context of two web application platforms: Microsoft and Java. A survey shows that the relative model can explain a high percentage of the variance in choice intention and actual choice. The results suggest that each product may have its own forte, with a different set of important factors. Applying the relative model to examine competing products can capture different dimensions and strengths to differentiate impacts on choice of alternative products. Factors that appear to be important for single-product analyses may not be important in a relative analysis. This highlights the importance of having a relative model study over separate single-product studies. © 2006 IEEE.