A Usability Evaluating Method For Website Based On Users’ Affective Experience

Usability is an important index to measure the quality of products. The level of usability directly impact on product’s quality. How to evaluate the usability of a product is also a significant link of product designing. At present, both at home and abroad researches on usability evaluation methods for websites are mostly examining users’ subjective assessments from a qualitative point of view, or considering error rate, completion time and other performance indicators to assess from a quantitative point of view. These assessment methods are single, lack of theoretical basis and technical support. Meanwhile, the traditional usability evaluating methods are all take the overall website as the research object. They are unable to pinpoint the factors what affect the level of usability.To solve the above problems, a new usability evaluating method for website based on users’ affective experience which combined traditional usability evaluating methods, eye tracking technology and physiological techniques was put forward.Firstly, in order to determine the usability evaluation node, the CTT model was used to split the experiment task. Secondly, a usability evaluation scale was proposed considering the characteristics of the website. Thirdly, the eye movement data, physical data and the usability evaluation scale date for each node of 18 subjects was collected through experiment study. And then the eye movement indexes and the physiological indexes which can reflect the level of usability were selected through ANVOA. Finally a relation model about eye movement indexes, physiological index model and usability was established by PLS and SVR. And the two models were tested, analyzed and interpreted.The results showed that fixation count, saccade count, pupil size, count fixation dispersion total, heart rate and other indicators all can reflect the usability level of the website. In addition to the size of the pupil diameter had a positive impact on usability, the other indicators were all negative. Because users’ pupil diameter sizes reflected the level of interest in which they observed. When the size of the pupil diameter was larger, users were more interested in the content of the website which can reflect a high level of website usability. While other indicators higher the value indicated the users’ visual search efficiency was lower. Namely it was unable to find what they want in a short time, which can show that website usability was low.In this paper, we proposed a new objective method to evaluate website usability considering the users’ affective experience, which can accurately locate bottlenecks affecting the level of usability. It can provide useful advice to product designers to improve product’s usability, which has a strong application value.