ScanGraph: A Novel Scanpath Comparison Method Using Visualisation of Graph Cliques

The article describes a new tool for analyses of eye-movement data. Many different approaches to scanpath comparison exist. One of the most frequently used approaches is String Edit Distance, where the gaze trajectories are replaced by the sequences of visited Areas of Interest. In cartographic literature, the most commonly used software for scanpath comparison is eyePatterns. During the analysis of eyePatterns functionality, we have found that tree-graph visualization of its results is not reliable. Thus, we decided to develop a new tool called ScanGraph. Its computational algorithms are modified to work better with the sequences with different lengths. The output is visualized as a simple graph, and similar groups of sequences are displayed as cliques of this graph. The article describes ScanGraph’s functionality on the example of a simple cartographic eye-tracking study. Differences of the reading strategy of a simple map between cartographic experts and novices were investigated. The paper should serve to the researchers who would like to analyze differences between groups of participants, and who would like to use our tool - ScanGraph, available at www.eyetracking.upol.cz/scangraph

Hypermobility of the first metatarsal bone in patients with Rheumatoid arthritis treated by lapidus procedure

BACKGROUND: Foot deformities and related problems of the forefoot are very common in patients with rheumatoid arthritis. The laxity of the medial cuneometatarsal joint and its synovitis are important factors in the development of forefoot deformity. The impaired joint causes the first metatarsal bone to become unstable in the frontal and sagittal planes. In this retrospective study we evaluated data of patients with rheumatoid arthritis who underwent Lapidus procedure. We evaluated the role of the instability in a group of patients, focusing mainly on the clinical symptoms and X-ray signs of the instability. METHODS: The study group included 125 patients with rheumatoid arthritis. The indications of the Lapidus procedure were a hallux valgus deformity greater than 15 degrees and varus deformity of the first metatarsal bone with the intermetatarsal angle greater than 15 degrees on anterio-posterior weight-bearing X-ray. RESULTS: Data of 143 Lapidus procedures of 125 patients with rheumatoid arthritis, who underwent surgery between 2004 and 2010 was evaluated. Signs and symptoms of the first metatarsal bone instability was found in 92 feet (64.3%) in our group. The AOFAS score was 48.6 before and 87.6 six months after the foot reconstruction. Nonunion of the medial cuneometatarsal joint arthrodesis on X-rays occurred in seven feet (4.9%). CONCLUSION: The Lapidus procedure provides the possibility to correct the first metatarsal bone varus position and its instability, as well as providing the possibility to achieve a painless foot for walking. We recommend using the procedure as a preventive surgery in poorly symptomatic patients with rheumatoid arthritis in case of the first metatarsal bone hypermobility

Eye-tracking Analysis of Interactive 3D Geovisualization

This paper describes a new tool for eye-tracking data and their analysis with the use of interactive 3D models. This tool helps to analyse interactive 3D models easier than by time-consuming, frame-by-frame investigation of captured screen recordings with superimposed scanpaths. The main function of this tool, called 3DgazeR, is to calculate 3D coordinates (X, Y, Z coordinates of the 3D scene) for individual points of view. These 3D coordinates can be calculated from the values of the position and orientation of a virtual camera and the 2D coordinates of the gaze upon the screen. The functionality of 3DgazeR is introduced in a case study example using Digital Elevation Models as stimuli. The purpose of the case study was to verify the functionality of the tool and discover the most suitable visualization methods for geographic 3D models. Five selected methods are presented in the results section of the paper. Most of the output was created in a Geographic Information System. 3DgazeR works with generic CSV files, SMI eye-tracker, and the low-cost EyeTribe tracker connected with open source application OGAMA. It can compute 3D coordinates from raw data and fixations

Accuracy and precision of fixation locations recorded with the low-cost Eye Tribe tracker in different experimental set-ups

This article compares the accuracy and precision of the low-cost Eye Tribe tracker and a well-established comparable eye tracker: SMI RED 250. Participants were instructed to fixate on predefined point locations on a screen. The accuracy is measured by the distance between the recorded fixation locations and the actual location. Precision is represented by the standard deviation of these measurements. Furthermore, the temporal precision of both eye tracking devices (sampling rate) is evaluated as well. The obtained results illustrate that a correct set-up and selection of software to record and process the data are of utmost importance to obtain acceptable results with the low-cost device. Nevertheless, with careful selections in each of these steps, the quality (accuracy and precision) of the recorded data can be considered comparable

Tvorba nástrojů pro analýzu dat z ET2Spatial v prostředí GIS

Grantová podpora: Identifikace bariér v procesu komunikace prosto rových sociálně-demografických informací (23-06

EyeTribe Tracker Data Accuracy Evaluation and Its Interconnection with Hypothesis Software for Cartographic Purposes

The mixed research design is a progressive methodological discourse that combines the advantages of quantitative and qualitative methods. Its possibilities of application are, however, dependent on the efficiency with which the particular research techniques are used and combined. The aim of the paper is to introduce the possible combination of Hypothesis with EyeTribe tracker. The Hypothesis is intended for quantitative data acquisition and the EyeTribe is intended for qualitative (eye-tracking) data recording. In the first part of the paper, Hypothesis software is described. The Hypothesis platform provides an environment for web-based computerized experiment design and mass data collection. Then, evaluation of the accuracy of data recorded by EyeTribe tracker was performed with the use of concurrent recording together with the SMI RED 250 eye-tracker. Both qualitative and quantitative results showed that data accuracy is sufficient for cartographic research. In the third part of the paper, a system for connecting EyeTribe tracker and Hypothesis software is presented. The interconnection was performed with the help of developed web application HypOgama. The created system uses open-source software OGAMA for recording the eye-movements of participants together with quantitative data from Hypothesis. The final part of the paper describes the integrated research system combining Hypothesis and EyeTribe