Searching for the ‘Right’ Legend: The Impact of Legend Position on Legend Decoding in a Cartographic Memory Task

ABSTRACT

Map legends are key elements of thematic maps and cartographic communication. The question of how to style map legends is a topic which has often been addressed by cartographic academics and practitioners. Nevertheless, the question of where to position a map legend has only hardly been discussed. Principles of cognitive sciences allow the assumption that a legend positioned to the right of a map field can be read and decoded faster than a legend on the left side. This study investigates the impact of legend positioning on legend decoding. It involves an experiment based on a recognition memory paradigm and the registration of eye-movements. The results show that, in less time, a legend positioned to the right of the map field (compared to a left legend) can be decoded faster. The same accuracy of a cognitive representation of geographic space can be achieved in spatial memory.     

Map Libraries

Colour distortion, which is caused by the unavoidable mismatch between a map’s gamut and a device’s gamut, negatively affects the semiotic quality of maps. Cartographic communication often suffers from undesirable colour inconsistency. This method models cartographic colour reproduction as a constrained transform problem, namely, adapting a map’s gamut to fit a device’s gamut while preserving the semiotic quality. First, the characteristics of the map’s gamut are investigated by considering cartographic principles, and the fundamental concerns of preserving semiotic quality are proposed. Then, the self-organizing map method is introduced to iteratively optimize the cartographic colour reproduction. We implement this method and evaluate it based on a series of thematic maps. The results indicate that the proposed algorithm offers better results than two alternatives in terms of facilitating cartographic colour reproduction.     

增强地图服务,做大地理信息板块

回顾了北京市测绘设计研究院二十多年地理信息产业的发展历史,分析了所面临的机遇与挑战,认为空间数据的可视化输出-地图生产是地理信息产业的主要任务之一。搞好这项工作应建立GIS数据库到地图数据库的双向通道;扩展地图数据库的地图制图和桌面出版功能;编制好系列基础底图和社会公众普遍需要的普通地图、政区图、地名图、交通旅游图,逐步实现编制导航地图,争取导航电子地图资质;做好用户需求调查,编制若干专题地图产品;开发影像地图、三维地图、实景地图等地理信息新品种;跟踪国家开展的各类普查或调查项目,编制高科技含量的地图集。     

地图信息论:从狭义到广义的发展回顾

地图是人类认识客观世界的有力工具。地图的核心功能是传输空间信息。自20世纪60年代源自通信领域的信息论被引入地图信息度量.现代地图学已经发展了一个崭新的研究领域——地图信息论。本文旨在对近50年来地图信息论的发展历程进行回顾,论述从狭义到广义地图信息论的基本概念、研究进展及应用领域,最后对地图信息论的发展进行了展望。     

论ICT时代的泛地图表达

信息通信技术的发展,赋予了地图表达极大的自由度,地图学的复兴促进了泛地图的发展。本文系统分析了地图定义的演变,适时论述了泛地图的概念,将传统的标准地图与各种创新形式的类地图纳入统一的泛地图框架下,提出并剖析了泛地图表达的标准地图、写实地图和写意地图分类体系,讨论了泛地图类型、风格化、连续性表示对泛地图表达的作用。     

Generating and mapping population density surfaces within a geographical information system

Abstract

The spatially discontinuous choropleth map is a poor representation of the underlying continuous distribution of population density. A possible alternative is to derive dasymetric maps at a fine spatial resolution by making use of satellite imagery in a geographical information system. However, there are cartographic problems when these maps are displayed and further processing is needed in order to obtain approximations to a continuous density surface. Isarithmic maps of these density surfaces retain a high degree of spatial accuracy while providing pleasing and highly adaptable presentations.

The methods used to generate dasymetric and isarithmic maps are readily implemented in most raster based geographical information systems. For example, the classification of remotely sensed imagery, the subsequent processing and integration of data, and most of the cartographic display, were all undertaken in this work using the low cost IDRISI GIS that operates on standard IBM PC compatible hardware.     

地图语言信息传输方式研究

地图语言是地图制图学理论的常用术语,多种地图产品如多媒体地图、电子导航地图等的出现使得传统地图信息传输方式的研究需要进一步扩展。分析地图语言和自然语言的概念,分别从视觉、听觉及触觉方面讨论两种语言在信息传输方式上的异同点。借鉴自然语言的多通道传输方式,探讨地图信息传输的多感知表现形式,为地图符号设计提供新的思路。     

Representation and its Relationship with Cartographic Visualization

A research agenda is presented which addresses the current role and potential of map displays. By considering the geospatial data used in visualization, the form and design of maps, the purposes for which map displays are created, the nature of the map user community, and the technology employed to visualize geospatial data, a thorough overview of the nature of cartographic visualization is given. Under the same themes, and sourced in cartographic tradition, cartographic practice and technological opportunities, a series of possible research avenues are highlighted. The important links between representation and the user interface, map user cognition and the geospatial database are stressed.     

地图数学定义的研究

在地图内容和形式数学表示的基础上研究了地图的数学定义。由于引入隐式地图和变换条件,故所有储存地图信息的载体均可属于地图的范围,从而使地图定义获得了广义的解释和精确的表达。     

Hexagon Mosaic Maps for Display of Univariate and Bivariate Geographical Data

This paper presents concepts that motivate the use of hexagon mosaic maps and hexagon-based ray-glyph maps. The phrase "hexagon mosaic map" refers to maps that use hexagons to tessellate major areas of a map, such as land masses. Hexagon mosaic maps are similar to color-contour (isarithm) maps and show broad regional patterns. The ray glyph, an oriented line segment with a dot at the base, provides a convenient symbol for representing information within a hexagon cell. Ray angle encodes the local estimate for the hexagon. A simple extension adds upper- and lower-confidence bounds as a shaded arc bounded by two rays. Another extension, the bivariate ray glyph, provides a continuous representation for showing the local correlation of two variables. The theme of integrating statistical analysis and cartographic methods appears throughout this paper. Example maps show statistical summaries of acidic deposition data for the eastern United States. These maps provide useful templates for a wide range of statistical summarization and exploration tasks. Correspondingly, the concepts in this paper address the incorporation of statistical information, visual appeal, representational accuracy, and map interpretation.     

A Cognitive Map Experiment: Mental Representations and the Encoding Process

Researchers have long debated the mental representation of knowledge. The theories initially spawned by this debate were propositional theoty, imagery theory, and dual-coding theory. Related research further suggests that knowledge encoding processes such as landmark-based and path-based learning may also affect these representations. Such theories form a basis from which cartographers can begin to explore the mental representations of spatial knowledge. The purpose of this study was to assess the mental organization of spatial information and to examine the effect of varying the encoding process. An experiment was conducted in which subjects studied a map presented to them using one of three encoding processes and one of two grid conditions. Subjects then examined a series of test maps and determined whether each map was the same as or different from the original studied map. Test maps that differed from the original map studied were modified by either replacing, displacing, or reversing the perspective of a map object. Results of the study indicated that the type of encoding process, type of map modification, and type of spatial object manipulated all significantly affected the accuracy with which subjects completed the tasks.     

The design and composition of persuasive maps

Persuasive maps are ubiquitous in society, yet cartographers have largely neglected to conduct serious, holistic research on them. Persuasive maps represent a form of visual communication that differs markedly from scientific geovisualization. First, many of these maps' communicative goals are anathema to those of scientific representation. Second, many persuasive maps ignore and defy established cartographic conventions. This article argues two things. First, the cartographic discipline can gain insight about how maps communicate information from the longitudinal and holistic analysis of persuasive maps. By comparing the differences and similarities of persuasive maps to scientific geovisualizations, researchers can begin to understand how persuasive maps communicate differently than scientific ones. Second, breaking persuasive maps down into composite parts may make it possible to identify persuasive map norms (i.e., methods of design that are embraced by producers of persuasive maps). The results of a content analysis of 256 persuasive maps are discussed. The article concludes that it may be possible to take the most statistically significant results from this study to begin identifying different rhetorical styles of persuasive maps.     

论中小比例尺政区形式地图的更新编辑

更新编辑中小比例尺政区形式地图主要是在现有数据的基础上,充分利用现势性较好的相关资料对已有数据进行修改、补充、完善,并且在色彩和地图表现形式上进行新颖的加工处理。更新编辑过程中,涉及地图要素内容比较复杂,需要有丰富的制图经验和多层面的色彩设计理念,将地图的视觉效果和艺术价值达到较高水平[1]。更新编辑中要保证成图数学精度,还要进行制图综合,表达合理各要素关系。下面以更新编制1∶550 000辽宁省地图为例详细地介绍一下中小比例尺政区形式地图的更新编辑过程。     

大数据时代综合性城市地图集设计的思考

大数据时代,数据要素和信息通信技术变革给综合性城市地图集的设计带来一系列新挑战,包括制图对象拓展到城市三元空间,制图内容聚焦大数据揭示的"城市性格",地图符号表达融合信息图表设计,地图阅读方式趋向"线上线下"融合等。城市地图集设计亟需适应时代特征,从科学、技术、设计、文化、媒体和产业6个维度寻求创新突破。以2020版的《深圳市地图集》为例,分析其空间、时间和属性3条设计主线,以及在内容体系、地图表达和工艺集成等方面的创新。     

地图集认知功能设计实践——以《中国市售水果蔬菜农药残留水平地图集》为例

地图可视化设计常包含地图认知功能设计、信息传输功效设计、地图视觉效果设计。其中地图认知功能设计是地图集的设计中最基本且最重要的环节。在此环节中,原始数据经过数据形态分析、数据处理与转化、制图模型的建立等过程,形成制图数据以及地图集的内容体系结构。本文以《中国市售水果蔬菜农药残留水平地图集》的设计为例,展示了地图集的地图认知功能设计过程。这个过程体现了地图信息论、地图模型论和地图空间认知论的思想,蕴含了地图的思想美、科学美、技术美和功能美。     

可视化与地图普及教育

现代可视化使地图的功能发生了根本的变化,地图作者的数量在可视化的兴起中迅速增长。这种现象不仅具有一定的理论基础,而且可以从可视化实践中得到论证。中国学术期刊数据库中与地图相关的论文统计结果证明地图应用具有越来越广泛的趋势。地图普及教育是十分必要的。以普及性教育为出发点,作者对地图学课程从理论、实践和教学方法等方面提出了具体的教改建议,并进一步提出为地学以外的所有专业开设地图通识课和建设地图知识普及网站等措施。     

三元空间下的泛地图可视化维度

信息通信时代促生地图的对象空间与表达空间发生了巨大变化,地图可视化理论面临空前挑战。针对泛地图的表达特点,构建泛地图可视化维度体系,给出了三元空间下泛地图可视化的研究框架,分析了泛地图可视化维度的层次、类型和特征,以具体的表达手段、状态、读图者视角、可视范围、变形、空间变换、空间参考等11个维度解构三元空间下的泛地图可视化模型,详细列出了其中6个可视化维度,并以迁徙地图、虚拟地图为例,分析不同维度组合下的泛地图可视化特征,拓展现有地图学理论框架。     

泛地图学理论研究框架

信息与通信技术的快速发展带动人类进入地理空间、人文社会空间和信息空间相融合的三元空间。地图制图的目的、人员、对象和环境等均发生巨大变化,地图的类型、空间对象、表达维度、地图角色等呈现出显著泛化特征,现有地图学理论无法引领和指导当代的地图实践。地图学理论亟待"突围"。从地图学研究的角度出发,重新梳理泛地图的对象空间理论、表达维度模型,以及表达机制与方法,构建适应新环境背景,满足地图新视角、新思维、新制图需求的泛地图学理论框架,以适应地图学在新时期发展的需要。