Computer interface evaluation using eye movements: methods and constructs

Eye movement-based analysis can enhance traditional performance, protocol, and walk-through evaluations of computer interfaces. Despite a substantial history of eye movement data collection in tasks, there is still a great need for an organized definition and evaluation of appropriate measures. Several measures based upon eye movement locations and scanpaths were evaluated here, to assess their validity for assessment of interface quality. Good and poor interfaces for a drawing tool selection program were developed by manipulating the grouping of tool icons. These were subsequently evaluated by a collection of 50 interface designers and typical users. Twelve subjects used the interfaces while their eye movements were collected. Compared with a randomly organized set of component buttons, well-organized functional grouping resulted in shorter scanpaths, covering smaller areas. The poorer interface resulted in more, but similar duration, fixations than the better interface. Whereas the poor interface produced less efficient search behavior, the layout of component representations did not influence their interpretability. Overall, data obtained from eye movements can significantly enhance the observation of users' strategies while using computer interfaces, which can subsequently improve the precision of computer interface evaluations.

Relevance to industry

The software development industry requires improved methods for the objective analysis and design of software interfaces. This study provides a foundation for using eye movement analysis as part of an objective evaluation tool for many phases of interface analysis. The present approach is instructional in its definition of eye movement-based measures, and is evaluative with respect to the utility of these measures.     

Object-oriented program tracing and visualization

Conventional program analysis and presentation techniques are insufficient when dealing with object oriented concepts, but tool developers have nevertheless found a way to obtain and visualize OO traces. The approach presented combines static information with actual execution information to produce views that summarize the relevant computation. In developing this approach, the authors focused on reducing the search space for extracting dynamic program information and on creating visualizations that may improve a programmer's understanding of object behaviour in real world OO systems. They applied the research prototype, Program Explorer, to a real project outside IBM. Although Program Explorer was originally designed for C++, a version for IBM's System Object Model (SOM) has demonstrated that the concepts are applicable to OO languages in general     

The impact of multimedia effect on science learning: Evidence from eye movements

This study examined how middle school students constructed their understanding of the mitosis and meiosis processes at a molecular level through multimedia learning materials presented in different interaction and sensory modality modes. A two (interaction modes: animation/simulation) by two (sensory modality modes: narration/on-screen text) factorial design was employed. The dependent variables included subjects’ pre-test, post-test, and retention-test scores, showing their understanding of mitosis and meiosis process at molecular level, as well as data of subjects’ eye-movement behavior. Results showed the group that received animation with narration allocated a greater amount of visual attention (number of fixations, total inspection time, and mean fixation duration) than the group that received animation with on-screen text, in both pictorial area and area of interest, which is consistent with students’ immediate and long-term retained learning of the processes of mitosis and meiosis. The group that received simulation with on-screen text allocated a greater amount of visual attention than the group that received simulation with narration, consistent with students’ immediate and retained learning. The group that received simulation with on-screen text also allocated a greater amount of visual attention than the group that received animation with on-screen text, consistent with students’ immediate and retained learning. This study adds empirical evidence of a direct correlation between the length of eye fixation behavior and the depth of learning. Moreover, it provides insight into the multimedia effect on students’ cognitive process through the use of eye fixation behavior evidence.     

Using eye movements to evaluate a PC-based risk awareness and perception training program on a driving simulator

OBJECTIVE: Evaluation of the effects of a PC-based training program on risk perception in a driving simulator. BACKGROUND: Novice drivers have a fatality rate some eight times higher than that of the most experienced group of drivers, primarily because of the novice driver's inability to predict ahead of time the risks that will appear in the roadway. Current driver education programs, at least those in the United States, do not emphasize the teaching of risk awareness skills to novice drivers. METHOD: A PC-based risk awareness and perception training program was developed and evaluated. The training involved using plan (top-down) views of 10 risky scenarios that helped novice drivers identify where potential risks were located and what information should be attended. Both the 24 trained novice drivers and 24 untrained novice drivers were evaluated on an advanced driving simulator. The eye movements of both groups of drivers were measured. The evaluation on the driving simulator included both scenarios used in the training and others not used in training. RESULTS: The set of trained novice drivers were almost twice as likely as untrained drivers to fixate appropriately either on the regions where potential risks might appear or on signs that warned of potentially risky situations ahead, both for the scenarios they had encountered in training and for novel scenarios. APPLICATION: The PC training program developed, which is portable and can be widely used, has great promise in improving risk perception for novice drivers on the road.     

Fault management in process control: eye movements and action

Operators controlled a simulated thermal hydraulic system based on Crossman's waterbath task. They were required to keep the system at set points for temperature, level and flow rates. The system was subjected to disturbances and to failures, which the operators were required to manage. Behavioural data were collected in the form of keystroke commands, and in addition eye movements were measured. Evidence for 'cognitive lockup' and for a preference for serial fault management were found. Fixation durations do not change, but faulty subsystems are examined more frequently. During lockup other subsystems may be examined but action on them is delayed. Eye movements give considerable additional insight into the nature of process control information processing compared with traditional measures of operator performance.     

Fault management in process control: eye movements and action

Operators controlled a simulated thermal hydraulic system based on Crossman's waterbath task. They were required to keep the system at set points for temperature, level and flow rates. The system was subjected to disturbances and to failures, which the operators were required to manage. Behavioural data were collected in the form of keystroke commands, and in addition eye movements were measured. Evidence for ‘cognitive lockup’ and for a preference for serial fault management were found. Fixation durations do not change, but faulty subsystems are examined more frequently. During lockup other subsystems may be examined but action on them is delayed. Eye movements give considerable additional insight into the nature of process control information processing compared with traditional measures of operator performance.     

Identification of eye movements from non-frontal face images for eye-controlled systems

The novel eye-based human-computer interaction(HCI) system aims to provide people, especially, disabled persons,a new way of communication with surroundings. It adopts a series of continual eye movements as input to perform simple control activities. Identification of eye movements is the crucial technology in these eye-based HCI systems. At present, researches on eye movement identification mainly focus on frontal face images. In fact, acquisition of non-frontal face images is more reasonable in real applications. In this paper, we discuss the identification process of eye movements from non-frontal face images. Firstly, the original head-shoulder images of 0?–±60?azimuths are sampled without any auxiliary light source. Secondly, the non-frontal face region is detected by using the Adaboost cascade classifiers. After that, we roughly extract eye windows by the integral projection function.Then, we propose a new method to calculate the x- y coordinates of the pupil center point by searching the minimal intensity value in the eye windows. According to the trajectory of the pupil center points, different eye movements(eye moving left, right, up or down)are successfully identified. A set of experiments is presented.     

The impacts of banner format and animation speed on banner effectiveness: Evidence from eye movements

Given that banner ad investment is huge and keeps increasing, the effectiveness of banners is important for advertising practitioners and is worth attention from academics. Banner properties (e.g. format and animation) may influence the overall effectiveness of banners. However, research on how banner formats (e.g. location and orientation) affect banner effectiveness is still in its early stage and studies on how animation influences banner effectiveness have also found controversial results. By conducting an experiment using eye-tracking technology, this study investigated the impacts of banner properties, especially animation speed and format, on users' attention, recall, and attitudes towards banners. In terms of attention, both the main effects and the interaction effect were significant and the patterns varied across time. However, no significant effects were found on recall and attitudes.     

Medical students' cognitive load in volumetric image interpretation: Insights from human-computer interaction and eye movements

Medical image interpretation is moving from using 2D- to volumetric images, thereby changing the cognitive and perceptual processes involved. This is expected to affect medical students' experienced cognitive load, while learning image interpretation skills. With two studies this explorative research investigated whether measures inherent to image interpretation, i.e. human-computer interaction and eye tracking, relate to cognitive load. Subsequently, it investigated effects of volumetric image interpretation on second-year medical students' cognitive load. Study 1 measured human-computer interactions of participants during two volumetric image interpretation tasks. Using structural equation modelling, the latent variable ‘volumetric image information’ was identified from the data, which significantly predicted self-reported mental effort as a measure of cognitive load. Study 2 measured participants' eye movements during multiple 2D and volumetric image interpretation tasks. Multilevel analysis showed that time to locate a relevant structure in an image was significantly related to pupil dilation, as a proxy for cognitive load. It is discussed how combining human-computer interaction and eye tracking allows for comprehensive measurement of cognitive load. Combining such measures in a single model would allow for disentangling unique sources of cognitive load, leading to recommendations for implementation of volumetric image interpretation in the medical education curriculum.     

Virtual Eye: retinal image visualization of the human eye

In computer graphics, ray tracing produces realistic images of 3D scenes. Most work in the field has focused on modeling reflection to account for the interaction of light with different materials, deriving illumination algorithms to simulate light transport throughout the environment, and designing new optimization techniques. Additional work by (Cook et al., 1984) targeted simulation of depth of field and motion blur. Kolb and Hanrahan (1995) presented a realistic camera model that simulates aberration and radiation and produces images showing a variety of optical effects. Our challenge is to combine these two well-developed scientific fields to simulate human vision. We have begun to do so with the development of the Virtual Eye, a method to visualize retinal images. This article describes how the Virtual Eye simulates retinal perception and discusses its potential value in clinical applications such as planning and evaluating surgical techniques or new lens combinations     

Stream 3D: Computer graphics program for streamline visualization

The present streamline visualization program is based on the technique of mapping the physical domain to a rectangular block. The streamline computation proceeds by integrating the mapped velocity vectors in isoparametric cells and plotting the coordinates of the streamlines thus obtained. The mapping and interpolation use multilinear functions, and the streamline equations are integrated by the classical Runge-Kutta method with a heuristic strategy for stepsize selection. An example integrating the streamlines in the solution of a vortical flowfield over a delta wing at angle of attack demonstrates the use of the program.     

Qmol: a program for molecular visualization on Windows-based PCs

With the advent of powerful, inexpensive graphics hardware, a variety of molecular modelling tools are now available for personal computers (PCs). While a host of high-quality, free visualization programs exist for Unix-like operating systems, there are relatively few available for Microsoft Windows. Most programs that do run under Windows are designed to interactively visualize experimental data and cannot read binary trajectory data generated by molecular simulations. In addition, many of these programs do not accept command line arguments, limiting their ability to serve as a “helper” application to be run by other applications. To fill this gap in functionality, we present Qmol—a program designed for viewing the output of simulations and theoretical calculations of peptides and small molecules.     

Differences between beginning and advanced design students in analogical reasoning during idea generation: evidence from eye movements

Cognition, Technology & Work - In existing studies about analogical reasoning during idea generation in design, there is lack in quantitative and objective evidences showing the relationship...     

基于图形化热工水力测控程序的解释性加载设计

在热工水力测控系统中,常采用图形化编程的方式构建编程控件之间逻辑关系,形成所需的系统功能。程序的部署和运行时,若采用程序实时编译的模式,会带来编译时间长、编译环境复杂等问题。为了提高测控程序的开发效率,采用控件组件化的思想,进行图形化程序逻辑关系的分解与重构机制设计;提出程序模板+轻量级配置交件的模式,利用程序模板对配置交件进行解释性加载。在热工水力测控系统的测试验证中,利用基于解释性加载机制的图形化编程平台完成了其中测控软件的开发及运行,功能及数据结果准确无误。该解释性加载机制真实、有效,可实现图形化热工水力测控程序的快速部署与加载运行。     

基于网络的对称度误差评定及其可视化

以面对面对称度误差为例,讨论了网络环境下零件形位误差评定结果可视 化的具体方法,阐述了VRML 与Java 之间的通信机制与交互原理,并通过实例实现了以 VRML 作为三维展示平台、以Java Applet 作为控制核心的面对面对称度误差的评定及其结 果可视化。用户通过屏幕可直观观察到基准中心平面位置和各测点分布特征,为不合格零件 的修正和后续工艺的改进提供了依据。     

基于AOP的程序状态可视化方法研究与实现

论述了面向方面的编程（AOP）概念及其在处理横切关注点方面的优势,研究了其在程序状态可视化方面的应用,并利用AOP技术实现了一个表达式求值时的程序状态可视化的实例。程序状态可视化功能常常表现为一种横切关注点,相比利用面向对象的编程（OOP）来实现程序状态可视化功能,AOP技术提供了一种更加松耦合且更具模块性的实现方式。     

Dynamic analysis of Java program concepts for visualization and profiling

Concept assignment identifies units of source code that are functionally related, even if this is not apparent from a syntactic point of view. Until now, the results of concept assignment have only been used for static analysis, mostly of program source code. This paper investigates the possibility of using concept information within a framework for dynamic analysis of programs. The paper presents two case studies involving a small Java program used in a previous research exercise, and a large Java virtual machine (the popular Jikes RVM system). These studies investigate two applications of dynamic concept information: visualization and profiling. The paper demonstrates two different styles of concept visualization, which show the proportion of overall time spent in each concept and the sequence of concept execution, respectively. The profiling study concerns the interaction between runtime compilation and garbage collection in Jikes RVM. For some benchmark cases, we are able to obtain a significant reduction in garbage collection time. We discuss how this phenomenon might be harnessed to optimize the scheduling of garbage collection in Jikes RVM.     

Visual and memory search in complex environments: determinants of eye movements and search performance

Previous research on visual and memory search revealed various top down and bottom up factors influencing performance. However, utilising abstract stimuli (e.g. geometrical shapes or letters) and focussing on individual factors has often limited the applicability of research findings. Two experiments were designed to analyse which attributes of a product facilitate search in an applied environment. Participants scanned displays containing juice packages while their eye movements were recorded. The familiarity, saliency, and position of search targets were systematically varied. Experiment 1 involved a visual search task, whereas Experiment 2 focussed on memory search. The results showed that bottom up (target saliency) and top down (target familiarity) factors strongly interacted. Overt visual attention was influenced by cultural habits, purposes, and current task demands. The results provide a solid database for assessing the impact and interplay of fundamental top down and bottom up determinants of search processes in applied fields of psychology. Practitioner Summary: Our study demonstrates how a product (or a visual item in general) needs to be designed and placed to ensure that it can be found effectively and efficiently within complex environments. Corresponding product design should result in faster and more accurate visual and memory based search processes.