Investigating the effectiveness of an efficient label placement method using eye movement data

This paper focuses on improving the efficiency and effectiveness of dynamic and interactive maps in relation to the user. A label placement method with an improved algorithmic efficiency is presented. Since this algorithm has an influence on the actual placement of the name labels on the map, it is tested if this efficient algorithms also creates more effective maps: how well is the information processed by the user. We tested 30 participants while they were working on a dynamic and interactive map display. Their task was to locate geographical names on each of the presented maps. Their eye movements were registered together with the time at which a given label was found. The gathered data reveal no difference in the user's response times, neither in the number and the duration of the fixations between both map designs. The results of this study show that the efficiency of label placement algorithms can be improved without disturbing the user's cognitive map. Consequently, we created a more efficient map without affecting its effectiveness towards the user

Mixed labeling: Integration of internal and external labeling

Tato diplomová práce se zabývá automatickým rozmístěním popisků. Popisky mohou být umístěny přes daný objekt (angl. Internal Labelig) či vedle daného objektu (angl. External Labeling), přičemž jsou s ním spojeny čárou. V této práci se pokouším zkombinovat tyto dva přístupy a popisky umísťovat smíšeně. Zároveň se snažím popisky umístěné vně objektu umístit tak, aby k jejich asociaci s ním nebyla čára potřebná. V textu práce nejprve uvádím existující přístupy k této problematice. Následně analyzuji problémy spojené se smíšeným umísťováním popisků a na základně analýzy provádím implementaci. Funkčnost algoritmu je otestována na šesti modelech. Se třemi z nich je provedena uživatelská studie.This master thesis focuses on automatic label placement. Labels can be positioned over a given object (Internal Labeling) or next to it and connected by a line (External Labeling). I attempt to combine the two methods and position the labels in a mixed fashion. When I place the label next to the object, I try to pick such a position, that the line to connect it is not necessary. First, I present existing methods in the text. Subsequently, I analyze the problems related to mixed label placement. I carry out the implementation based on the analysis and test it with six models of various complexity. I evaluate with users in the end

Offline-Speicherung und Darstellung von Geodaten auf Mobilgeräten

Die Visualisierung von großen Mengen geographischer Basisdaten, wie Stadtnamen und Verwaltungsgebieten, ist mit verschiedenen Problemen verbunden. Werden zu viele Daten und Details auf zu kleinem Raum dargestellt, kann die Übersichtlichkeit der Darstellung leiden oder Überdeckung die Wahrnehmbarkeit einzelner Objekte stören. Ist eine Interaktion mit der Visualisierung möglich (beispielsweise durch verschieben, rotieren und zoomen des betrachteten Ausschnitts), kann eine große Menge an darzustellenden Daten Performanceprobleme verursachen und eine verzögerungsfreie Interaktion verhindern. Die vorliegende Diplomarbeit beschäftigt sich mit der Visualisierung von Ortslagen und Grenzsegmenten von Verwaltungsgebieten der Bundesrepublik Deutschland. In der Arbeit werden zwei Methoden entwickelt, um die entsprechenden Daten zu strukturieren und zu speichern. Die entwickelten Datenstrukturen ermöglichen eine einfache Ableitung von Teilmengen der gespeicherten Daten, die in einer Visualisierung konfliktfrei und gut wahrnehmbar dargestellt werden können. Für die Speicherung der Daten wird ein binäres Dateiformat entwickelt, das eine kompakte Speicherung der Datenstrukturen ermöglicht. Die Grenzsegmente der Verwaltungsgebiete können abhängig von ihrer Zugehörigkeit zu verschiedenen Verwaltungsebenen abgefragt werden. Um den Aufwand für das Zeichnen der Segmente zu verringern, können sie in verschiedenen Generalisierungsstufen abgefragt werden. Im Rahmen der Diplomarbeit wurden, basierend auf den entwickelten Datenstrukturen, zwei Visualisierungen der Daten entwickelt. Sie ermöglichen ein interaktives Erkunden der Datensätze mittels Verschiebung, Rotation und Zoom des dargestellten Datenausschnitts in Echtzeit auf einem PC und einem Android Gerät

Empirical evaluation of alternative cartographic solutions for the user interface of Abisko GIS

Over the last 15 years there has been a rapid increase in the development and usage of digital maps. Methods for assessing the quality of systems for communicating digital geographical information are frequently described in the literature, but few methods have been empirically evaluated. The quality of cartographic products is especially important for resources management and environmental planning, although it may be important in all application areas where spatial information is used. When designing digital communicative systems, it is crucially important to base system development on empirical interactions with potential users. In this thesis, empirical methods were used to develop a geographic information system (GIS) for environmental research and monitoring in the Arctic – the Abisko GIS. Approximately 30 potential users were interviewed via a questionnaire while testing a number of alternative interfaces to Abisko GIS. This allowed the qualities of alternative cartographic solutions to be evaluated and the optimal combination of cartographic objects to be implemented in Abisko GIS. Through statistical inference of the questionnaires, it was concluded that Map Design had the greatest effect on subjects during their evaluation. Gender and the Time spent with evaluation had no significant effect, although Time appeared to play some role for experts and those with experience of GIS. On average, the response to questions asked regarding particular aspects of maps varied diminutively across subjects. Other observations are discussed in the text

Label-EZ ™-- Software for Automated Cartographic Text Placement

The most time-consuming task of producing a map − after data collection − is that of labeling the point, line, and area features depicted on it. It is a task that has been performed by skilled human cartographers for centuries but one that has proven remarkably resistant to automation. The paper describes a research and development effort extending over nearly 25 years to develop a software system that would automate this task. The software now available – MapText’s Label-EZ – embodies the cartographer's rules and conventions and places the text for each feature according to a user-specified scenario, resolving pla cement conflicts and ambiguities over all feature layers in accordance with set placement priorities. Placement alternatives are automatically explored if the initial placement choice is not available because of lack of space, in a manner analogous to what a human cartographer could be expected to do under the same circumstances. The paper reviews the issues posed by the text placement problem and describes the solution for it that is now available.