Frank Dickmann

Grids in Topographic Maps Reduce Distortions in the Recall of Learned Object Locations

To date, it has been shown that cognitive map representations based on cartographic visualisations are systematically distorted. The grid is a traditional element of map graphics that has rarely been considered in research on perception-based spatial distortions. Grids do not only support the map reader in finding coordinates or locations of objects, they also provide a systematic structure for clustering visual map information (“spatial chunks”). The aim of this study was to examine whether different cartographic kinds of grids reduce spatial distortions and improve recall memory for object locations. Recall performance was measured as both the percentage of correctly recalled objects (hit rate) and the mean distance errors of correctly recalled objects (spatial accuracy). Different kinds of grids (continuous lines, dashed lines, crosses) were applied to topographic maps. These maps were also varied in their type of characteristic areas (LANDSCAPE) and different information layer compositions (DENSITY) to examine the effects of map complexity. The study involving 144 participants shows that all experimental cartographic factors (GRID, LANDSCAPE, DENSITY) improve recall performance and spatial accuracy of learned object locations. Overlaying a topographic map with a grid significantly reduces the mean distance errors of correctly recalled map objects. The paper includes a discussion of a square grids usefulness concerning object location memory, independent of whether the grid is clearly visible (continuous or dashed lines) or only indicated by crosses.

True-3D Accentuating of Grids and Streets in Urban Topographic Maps Enhances Human Object Location Memory

Cognitive representations of learned map information are subject to systematic distortion errors. Map elements that divide a map surface into regions, such as content-related linear symbols (e.g. streets, rivers, railway systems) or additional artificial layers (coordinate grids), provide an orientation pattern that can help users to reduce distortions in their mental representations. In recent years, the television industry has started to establish True-3D (autostereoscopic) displays as mass media. These modern displays make it possible to watch dynamic and static images including depth illusions without additional devices, such as 3D glasses. In these images, visual details can be distributed over different positions along the depth axis. Some empirical studies of vision research provided first evidence that 3D stereoscopic content attracts higher attention and is processed faster. So far, the impact of True-3D accentuating has not yet been explored concerning spatial memory tasks and cartography. This paper reports the results of two empirical studies that focus on investigations whether True-3D accentuating of artificial, regular overlaying line features (i.e. grids) and content-related, irregular line features (i.e. highways and main streets) in official urban topographic maps (scale 1/10,000) further improves human object location memory performance. The memory performance is measured as both the percentage of correctly recalled object locations (hit rate) and the mean distances of correctly recalled objects (spatial accuracy). It is shown that the True-3D accentuating of grids (depth offset: 5 cm) significantly enhances the spatial accuracy of recalled map object locations, whereas the True-3D emphasis of streets significantly improves the hit rate of recalled map object locations. These results show the potential of True-3D displays for an improvement of the cognitive representation of learned cartographic information.

City Maps Versus Map-Based Navigation Systems - An Empirical Approach to Building Mental Representations

Abstract Navigation systems are increasingly taking on the role of classic print maps for orientation in traffic. These electronic aids help to find the right route, but they hardly seem to contribute to spatial learning and thus the formation of long-term orientation knowledge. A practice-oriented efficiency comparison of a print map in form of a conventional city map and a navigation device provides first insights. The empirical results show that taking propositional and analogue spatial information from navigation systems leads to much weaker effects on cognitive mapping.

The Potential of the Lenticular Foil Technique for Thematic Cartography

Abstract title/> Lenticular visualisation methods are innovative advancements of modern presentation media in cartography. Owing to the mainly three-dimensional perception of people, this technique, in print as well as on screen, offers the possibility to introduce autostereoscopic, i.e. three-dimensional views in cartography. On the basis of true 3D, it has already found its way into the visualisation of relief relations. Moreover, it also opens perspectives for the more widespread products of thematic cartography (thematic maps). Multi-layered representation becomes possible on the basis of three-dimensional or sequentially differentiated depictions of spatial phenomena. Thus, several parameters or dimensions of cartographic content can be displayed at the same time. This essay discusses some potential applications of the lenticular foil technique for thematic cartography on a theoretical basis.

The Effects of Grid Line Separation in Topographic Maps for Object Location Memory

Research from the field of cognitive psychology provides evidence that cognitive representations of space based on maps or map-like sketches are subject to systematic distortion tendencies. These distortions influence the orientation capacity as they represent errors in spatial memory. Map grids are a traditional feature of map graphics that has rarely been considered in research on spatial distortions in cognitive maps. Grids traditionally assist the map reader in finding coordinates and objects, but they also provide a systematic and homogeneous structure for dividing up map information into smaller units supporting perception and spatial memory. In a previous study it was shown that grids improve object location memory. The aim of this study was to determine whether different sizes of grid cells have an effect on the quality of object location memory. Therefore, an empirical study including the test performances of 33 participants was carried out: the memory performance was measured as both the percentage of correctly recalled object locations (hit rate) and the mean distance errors of correctly recalled objects (spatial accuracy). Three different intervals of grid line spacing (Separation) were applied to topographic maps. These maps varied in their type of characteristic geographical areas, accompanied by three different levels of map complexity (Landscape). The results of this study show that both factors have an impact on object location memory in topographic maps. La recherche sur la psychologie cognitive démontre que les représentations cognitives de l’espace fondées sur des cartes ou des croquis ont tendance à faire l’objet de distorsion systématique. Ces distorsions influencent la capacité d’orientation puisqu’elles représentent des erreurs dans la mémoire spatiale. On a rarement tenu compte des grilles cartographiques, une caractéristique traditionnelle des représentations graphiques de cartes, lors des recherches sur les distorsions spatiales dans les cartes cognitives. Par tradition, les grilles aident le lecteur d’une carte à trouver les coordonnées et les objets, mais elles fournissent également une structure systématique et homogène qui permet de diviser les renseignements contenus sur une carte en de plus petites unités, facilitant ainsi la perception et la mémoire spatiale. Une étude réalisée antérieurement a démontré que les grilles améliorent la mémoire servant à localiser les objets; cet article décrit une expérience conçue pour déterminer si les différentes dimensions des cellules des grilles ont un effet sur la qualité de ce type de mémoire. Dans une étude empirique des performances réalisées par 33 participants à un test, la performance de la mémoire a été mesurée à la fois selon le pourcentage d’objets correctement localisés(taux de succès) et selon les erreurs de distance moyennes des objets correctement localisés(exactitude spatiale). Le test utilisait trois différents intervalles d’espacements des lignes des grilles (séparation), intervalles appliqués à des cartes topographiques de diverses régions géographiques selon trois différents niveaux de complexité cartographique (topographie). Les résultats ont révélé que les facteurs pour la séparation et la topographie ont tous deux des effets sur la mémoire servant à localiser les objets sur les cartes topographiques.

Z-axis Based Visualization of Map Elements – Cartographic Experiences with 3D Monitors Using Lenticular Foil Technology

Abstract The current advent of autostereoscopic monitors and TV screens using lenticular foil technology proves the increasing desire to visualize movies, pictures, graphics or even maps in true-3D. These techniques could expand the cartographic ‘tool box’ drastically, implying that 3D is no longer limited to the well-known representation of landform characteristics. Major map design aspects of multi-image models have been analyzed and evaluated regarding their use in thematic cartography. For map design using lenticular foil technology empirical findings are necessary to position layers adequately along the z-axis of a 3D depiction. Hovering layers may generate additional information values, which seem to be able to compensate the shortcomings in 2D maps. Several parameters or dimensions of cartographic contents can be displayed simultaneously. True-3D display techniques must be implemented in a differentiated manner to achieve positive impacts on cartographic communication. However, lenticular foil technique opens perspectives for more diverse products in thematic cartography.

Spreading Map Information over Different Depth Layers - An Improvement for Map-Reading Efficiency?

In recent years, True-3D representations such as lenticular visualization have entered the stage of analogue and, especially, digital cartography. The increase of 3D displays as products of mass media raises some fundamental questions about a new generation of 3D maps. Auto-stereoscopic displays allow cartographers to design 3D maps covering several information layers located at different positions along the depth axis. However, it remains unclear whether the opportunity to spread map information over different information depth layers can improve cartographic communication by helping to increase the duration and accuracy of map reading. This article presents the results of an empirical study, based on the test results achieved by 83 geography students who counted different map symbols in a series of 2D or 3D thematic maps of differing complexity.Au cours des dernières années, les représentations tridimensionnelles vraies comme la visualisation lenticulaire ont atteint le stade de l’analogie et particulièrement la cartographie numérique. L’augmentation des affichages 3D dans les médias de masse soulève quelques questions fondamentales relatives à une nouvelle génération de cartes 3D. Les affichages auto-stéréoscopiques permettent aux cartographes de dessiner des cartes 3D couvrant plusieurs couches d’informations se trouvant à différentes positions sur l’axe de la profondeur. Toutefois, on ne sait toujours pas avec certitude si la possibilité d’étaler les renseignements cartographiques sur différentes couches de profondeur peut améliorer la communication cartographique en contribuant à l’augmentation de la durée et de l’exactitude de la lecture de la carte. Cet article présente les résultats d’une étude empirique réalisée par 83 étudiants en géographie qui ont compté les résultats de différents tests dans une série de cartes thématiques 2D ou 3D de complexité différente.

Audiovisual communication of object-names improves the spatial accuracy of recalled object-locations in topographic maps

Knowing the correct location of a specific object learned from a (topographic) map is fundamental for orientation and navigation tasks. Spatial reference systems, such as coordinates or cardinal directions, are helpful tools for any geometric localization of positions that aims to be as exact as possible. Considering modern visualization techniques of multimedia cartography, map elements transferred through the auditory channel can be added easily. Audiovisual approaches have been discussed in the cartographic community for many years. However, the effectiveness of audiovisual map elements for map use has hardly been explored so far. Within an interdisciplinary (cartography-cognitive psychology) research project, it is examined whether map users remember object-locations better if they do not just read the corresponding place names, but also listen to them as voice recordings. This approach is based on the idea that learning object-identities influences learning object-locations, which is crucial for map-reading tasks. The results of an empirical study show that the additional auditory communication of object names not only improves memory for the names (object-identities), but also for the spatial accuracy of their corresponding object-locations. The audiovisual communication of semantic attribute information of a spatial object seems to improve the binding of object-identity and object-location, which enhances the spatial accuracy of object-location memory.

Exploiting Illusory Grid Lines for Object-Location Memory Performance in Urban Topographic Maps

In order to be successful in spatial orientation tasks, people need to recall locations and configurations of spatial objects from their memory. This understanding of geographic space often arises from experience with cartographic media representing topographic and topological information by graphic symbols. Learning spatial information from graphic media is influenced by different perception-based grouping effects distorting the accuracy of spatial object-positions and their relations. Such geometric inaccuracies can be softened by adding a grid layer, which regionalizes the map and can be used as an additional orientation pattern. This grid layer usually consists of solid lines and overlays semantic information. The present paper reports the results of two empirical studies on object-location memory (OLM) performance. In these studies, the amount of visual detail of the grid layer was reduced. By positioning the grid layer below specific urban topographic objects (study 1), the grid pattern was graphically interrupted. These interrupted grid lines were completed by cognitive completion mechanisms (illusory grid lines) described in the Gestalt principles of closure and continuation. The second experiment examined the maximum grid line gap that is closed by cognitive line completion and keeps an advantage for OLM (study 2).

Hexagonal map grids – an experimental study on the performance in memory of object locations

ABSTRACT In various every day contexts, maps are used as media supporting orientation, wayfinding, and navigation tasks. To create highly accurate and reliable maps, cartographers must be aware of cognitive effects that occur when people process map information. Interdisciplinary research from cognitive psychologists showed that map graphics lead to spatial distortions in human spatial memory. These distortions can influence human orientation capacities. Recently, it was discovered that grid structures overlaid on maps help to correct spatial distortions in cognitive representations of geographic space. Square grids chunk a map into smaller units (regions). They guide map-viewing behavior, and their regular structure helps map users to recall learned locations of objects more accurately. The effects caused by square grids may also occur when overlaying other common kinds of geometries, such as hexagonal structures. The effects of hexagonal grid structures on memory of object locations were investigated in this map-experimental study. The study design is based on a recall-memory-paradigm, an established method of experimental psychology to measure performance in memory. The results show that hexagonal grid patterns can improve the performance.