Multidimensional model to measure quality in e-commerce websites using item response theory

Abstract The goal of this article is to propose a multidimensional modeling to measure the quality of commercial websites with the use of Item Response Theory (IRT). The quality of a website encompasses technical characteristics (usability-navigability, presentation of information and interactivity) and non-technical characteristics (design, aesthetics, visual appeal, reliability, hedonism, image), theoretically configuring a multidimensional context. The initial hypothesis of the dimensions and the elaboration of the items were based on a bibliographic analysis about the theme of e-commerce website quality. A set of 75 items was prepared and submitted to a sample of 441 e-commerce websites from a wide variety of sectors. The treatment and analysis of data was conducted using IRT. In this step, questions related to dimensionality and the choice of the most suitable model was discussed. Finally, a multidimensional model with four dimensions was adjusted.摘要 本文旨在提出一种基于项目反应理论（Item Response Theory，IRT）的多维建模方法，以测评商业网站质量。网站质量涵盖技术特征与非技术特征：技术特征包括可用性与可导航性、信息呈现及交互性；非技术特征涵盖设计、美学、视觉吸引力、可靠性、享乐性与网站形象，从理论层面构建了多维研究情境。维度的初始假设与测评条目的编制，均基于针对电子商务网站质量主题开展的文献分析。研究共编制75条测评条目，并将其应用于覆盖多行业的441家电子商务网站样本。数据处理与分析环节采用IRT开展，在此过程中，研究人员围绕维度结构与最优模型选择等问题进行了探讨。最终，研究拟合得到包含四个维度的多维模型。