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.     

'Be Map Aware: Cutting-edge…Not Close to the Edge'

Abstract

An assessment is made of the accuracy of the map and written survey, which is essentially a list of land-holders and the areas held by each, and of their mutual consistency. The geometry of the map is compared quantitatively with that of the first edition (1852) Ordnance Survey 6-inch (1 : 10 560) map. The Saxton map is found to have a scale of 1 : 5140, leading to the conclusion that the perch used in the scale bar represents 7¹/₉ yards or thereabouts. The areas quoted in the written survey are consistent with acres based on this value. The positional accuracy of points on the map is found to be ～20 m, and areas of typical plots determined from the map are uncertain by between about 4 and 12%. The relationship between these two facts can be understood through a detailed study of the statistics of the errors in separations of points on the map. The written survey is found to omit a substantial number of plots of land from its listings. The map thus appears to be more reliable overall than the written survey.     

THE CADASTRAL MAP

Abstract

In the Empire Survey Review for April 1934 (No. 12, pp. 382–4), the Editor has raised the question of the function of the cadastral map. As he remarks, the question is not simple, but it is easier to say what the function of the map is than to decide of what the map should consist in order that it may fulfil its function. Broadly speaking we may state that the function of the map is to record the boundaries of landed property in such a manner as not only to afford a pictorial representation but also to supply data for the identification of these boundaries on the ground when occasion requires. Apart from this the map should show the areas of properties, as this information may be required for taxation purposes.     

Cartography: A manufacturing industry concerned with the Processing,Transformation, Packaging and Transportation of Spatial Data

Abstract

The communication approach advocated by cartographers during the past decade appears to have provided direction but no route to improvement of the product. Much of the research in this area appears almost aimless and considerable danger is foreseen in that if a path is not quickly established and maintained the purpose of cartographic research will be lost behind ill conceived forays into 'no man's land'. The map is considered within this article as primarily a 'total product' and interdependence between its various elements seen as its strength. The current obsession with component parts detached from their operating environment appears to provide nothing of use to the manufacturer. This paper certainly is not presented as either a research or review article, but rather as a contemplative essay in which the above topics are examined and comparisons made between the cartographic and other manufacturing industries.     

Objective and Subjective Comparison in Choroplethic Mapping

Abstract

Visual map comparison can supplement statistical analysis by providing information as to where and how spatial correspondence occurs. The associations that may be discovered are influenced by the nature of the map features being compared and the criteria used for making the comparisons. In this paper the author has tried to identify the elements of visual recognition that map readers use to associate or differentiate geographical distributions represented by choropleth maps. The main components of the multivariate map reading process are pointed out, including the perceptual interactions between the actual locations of map tones and the overall similarity between map patterns.     

ON THE CLASSIFICATION OF MAP PROJECTIONS

Abstract

1. Classes and Varieties. A map projection can be considered from different points of view, each such point of view representing a “class” of projections. The classes, in their turn, are subdivided into “varieties”.     

Mastering the Niger. James MacQueen’s African Geography and the Struggle Over Atlantic Slavery

Abstract

Since the publication of the first waterway map in 1990, the Inland Waterways of Britain series has expanded to a total of twenty three individual maps, a national route planning map, the first ring atlas and a directory of the inland waterways which explores aspects of preservation, restoration and heritage. Many of the titles have featured in walking guides, directories, promotional literature and web sites. This paper outlines the development of the series from the first map, describing the maps themselves, tracking the evolution of production methodologies, defining marketing and sales strategies and discussing the decision-making processes behind the publication and introduction of new titles.     

Recent Literature - Bookcase

Abstract

Why should a specialist sport require a map of its own? Trout fishing is not dependent on map use, but a carefully researched and presented map is a useful addition to the angler's tackle bag. The sport does not require the absolute planimetric accuracy of, say, an orienteering map, but careful research and selection of features is just as important. What information is essential to the angler and what is helpful? What is background information; and what, if anything, should be left off?     

ON THE ESSENCE OF THE LANGUAGE OF THE MAP

The author continues development of his concept of cartography as the “language of the map,” an earlier paper of this subject appearing in translation in M.S.R.S., 1985, No. 1. Although the term language has been widely used to describe cartographic communication, current theory fails to incorporate aspects of the language which provide for a comprehensive understanding of its structure and function. In particular, the language of the map and its symbolic elements cannot be explained reflexively by methods and rules of symbol and map design, since these elements were developed not before but after the existence of the language. The language of the map thus is proposed as the mechanism which provides for replicability or duplication in the way a system of mapmaking-map use functions (under diverse conditions, purposes, historical periods, and levels of training of users) through its different methods, models, and norms. Translated from: Geografiya i prirodnyye resursy, 1985, No. 3, pp. 142-151.     

A MAP OF THE EMPIRE

Abstract

About sixteen years ago an apparent need of the time led the writer to consider the construction of a small-scale map of the British Empire. It was immediately obvious that such a sheet, prepared in a manner to reduce the errors of scale and bearing to figures approaching the minimum, would have to extend from the Yukon and across the Eastern Hemisphere to New Zealand_ Accordingly, it would involve an oblique projection, cutting the Equator at some angle to be investigated. Moreover, the depth of the map would necessarily be the least possible in order to conform with the desiderata above.     

Influencing the Perception of Contour Lines

Abstract

Two possible causes of the failure of map users to successfully interpret relief forms from contour maps are Gibson's texture gradient effect which may give false depth cues; and, the expectancy or prior set developed from previous experience by the map reader. In the two experiments reported attempts were made to alter subjects' expectancy by providing cues or contextural information related to the task of interpreting a number of unquantified contour patterns. Although expectancy has proved to be a dominant influence on contour interpretation, successful priming in the experiments provided subjects with a number of conflicting but valid hypotheses which were often resolved in the direction of the texture gradient.     

SURVEY OF PALESTINE: THE FIRST TWENTY YEARS

Abstract

I suppose most of you look at a map nearly every day and I expect you know a good deal more about them after following the blitzkriege of armies in Europe—and Africa. My advice is, go on learning, for a map has become the means of picturing allsorts of things closely connected with our lives ; modern methods of reproduction have made maps so picturesque and useful that they should be companions to all those who take the trouble to understand them.     

Continuity markers as an aid for children in finding the peripheral continuity of world maps

ABSTRACT

Many map readers, including both children and adults, find it difficult to determine where they would be located along the edge of a world map after crossing that edge. Different types of markers have long been drawn close to the map’s edge – for example, in an atlas – to help map readers identify the map upon which they will find themselves if that edge is passed. In this study, a method similar to that used to show the continuity between maps in an atlas has been tested to determine whether continuity markers can also be used to help map readers find a world map’s actual peripheral continuity. The study involved children between the ages of 10 and 13 years and showed that continuity markers do help children determine the map’s actual peripheral continuity, in combination with a lesson that describes how to find the actual peripheral continuity of a world map. This article, therefore, concludes that continuity markers for world maps can be a useful part of map design that clarifies how the edges of a world map fit together for children who have learned to use this tool.     

Books

Abstract

This is a summary of the problems which are involved in the apparently trivial task of measuring the length of a sinuous line on a map. It represents an extended review of the publication Cartometric Measurements, by H. Kishimoto. It is concerned with three basic problems: (1) the sorts of errors which may result from using different instruments and methods of measurement and how these may be corrected: (2) the sorts of errors which may occur in the map and how these may be corrected: 3) the fundamental problem of what is 'length'. Extensive use is made of East European literature on these subjects.     

Pictorial Navigation Displays

Abstract

A pictorial navigation display for aircraft is described, in which the aircraft's ground position and track are continuously displayed, superimposed on the projected image in colour of a topographical map stored on microfilm. The microphotographic technique developed for preparation of the map films is also described. A navigation display of this type will be incorporated in the prototype Concorde supersonic airliner.     

Visual Abstraction and Stylisation of Maps

Abstract

We explore visual map abstraction for the generation of stylized renderings of 2D map data. We employ techniques that are centred around the concept of shape simplification and graph layout and that allow iterative abstraction of 2D maps. We use data from publicly available sources and show how we can iteratively generate aesthetic renditions of these maps. These renditions do not have the goal to allow for navigation tasks, but instead show the map data in a distorted manner. The techniques used to create these images apply simplification, abstraction/generalisation, and displacement operations to the map elements in varying orders and add stylistic shading to produce aesthetic renditions for print or electronic displays. The degree of abstraction/generalisation can be individually chosen and determines the characteristics of the distorted map: whether components retain their shape, degenerate, or are processed in a manner that the abstraction becomes the focus of the image rather than the underlying map data. The renditions can be further personalized by choosing shading and colours for this shading. Together, the presented techniques allow for playful and creative exploration of aesthetic renditions of 2D map data.     

An iterative approach for inverse transformation of map projections

ABSTRACT

Map projections are given by forward transformation equations. Inverse transformation is derived from forward transformation analytically or numerically. In this paper, a numerical approach for inverse transformation of map projections is proposed, which is based on numerical differentiation and Newton–Raphson root finding method. This approach can facilitate the program developments for map projections when inverse transformation is needed. Numerical differentiation is tested with three map projections. It is seen that seven-digit precision or more can be reached. Boundary conditions and initial guess problem in inverse transformation are discussed. In terms of initial guess, map projections are divided into three categories, and appropriate initial guess values for cylindrical, pseudocylindrical, azimuthal, and conical projections in normal aspect are suggested. Newton–Raphson method with numerical differentiation is tested with 20 different map projections by using test data sets. The results show that the proposed approach is applicable if appropriate initial guess is available.     

Problems of mapping a nature reserve: Aberlady Bay LNR and SSSI

Abstract

A new five-colour map of Aberlady Bay Local Nature Reserve and Site of Special Scientific Interest at 1:7,500 scale is published as a loose insert with the June 1993 issue of The Cartographic Journal. This accompanying paper describes the problems of producing the map at minimal cost, considers some of the cartographic issues particular to the site, and provides specification details of the compilation.

Such individual map sheets, which are used for environmental planning, research and teaching, have in the past been produced mainly by universities with the support of conservancy and countryside agencies. Future production costs at universities will inevitably rise although some economies may be possible by the use of digital database methods of cartography.     

Cartography in the GIS age

Abstract

At the end of the 1980s, the computer experts who had been in the vanguard of cartographic development lost their position due to the fact that computers became democratised. This may be ascribed to the 'Macintosh' effect. This in turn led cartographic companies back to the core of their professional know-how: it is cartographers themselves who now develop the scope of their profession, utilising all the resources provided by the new computer technology. But, if cartographers want to keep playing a major role in the geographic information arena, they have to determine and develop the specific elements of their discipline: if technology mobilizes all forces to the detriment of theory, then the discipline progressively weakens and ends in being swallowed by another discipline.

It is the cartographers' task to transform the spatial information from its verbal, social and numerical form into visual form for visual thinking; this visualisation provides for cognitive functions, communication functions, decision support functions and social functions. In order for maps to perform these functions cartographers should continue, now with digital tools, to safeguard data quality by monitoring the compilation stage during which they have to see to it that the heterogeneous datasets in databases will be made comparable, both from a geometrical, semantical, updatedness and completeness point of view. This main aspect of the cartographer's job can be called its engineering part. The other main aspect will remain the map design part, that leads to proper communication of the spatial information. Both aspects will remain the cartographer's domain if he/she succeeds in providing a theoretical basis for his/her work.     

A bevy of area-preserving transforms for map projection designers

ABSTRACT

Sometimes map projection designers need to create equal-area projections to best fill the projections’ purposes. However, unlike for conformal projections, few transformations have been described that can be applied to equal-area projections to develop new equal-area projections. Here, I survey area-preserving transformations, giving examples of their applications and proposing an efficient way of deploying an equal-area system for raster-based Web mapping. Together, these transformations provide a toolbox for the map projection designer working in the area-preserving domain.