Abstract: Information available for mapping continuous soil attributes often includes point field data and choropleth maps (e.g. soil or geological maps) that model the spatial distribution of soil attributes as the juxtaposition of polygons (areas) with constant values. This paper presents two approaches to incorporate both point and areal data in the spatial interpolation of continuous soil attributes. In the first instance, area-to-point kriging is used to map the variability within soil units while ensuring the coherence of the prediction so that the average of disaggregated estimates is equal to the original areal datum. The resulting estimates are then used as local means in residual kriging. The second approach proceeds in one step and capitalizes on: 1) a general formulation of kriging that allows the combination of both point and areal data through the use of area-to-area, area-to-point, and point-to-point covariances in the kriging system, 2) the availability of GIS to discretize polygons of irregular shape and size, and 3) knowledge of the point-support variogram model that can be inferred directly from point measurements, thereby eliminating the need for deconvolution procedures. The two approaches are illustrated using the geological map and heavy metal concentrations recorded in the topsoil of the Swiss Jura. Sensitivity analysis indicates that the new procedures improve prediction over ordinary kriging and traditional residual kriging based on the assumption that the local mean is constant within each mapping unit.

Abstract: The study reported here investigated the design and legibility of tactile thematic maps, focusing on symbolization and the comprehension of spatial patterns on the maps. The results indicate that discriminable and effective tactile thematic maps can be produced using classed data with a microcapsule paper production method. The participants demonstrated that they could describe the spatial data patterns that were displayed. ********** Thematic maps are cartographic representations of themes, such as population or income. These types of maps can show information about specific locations, give general information about spatial patterns, and be used to compare the patterns on two or more maps (Slocum, McMaster, Kessler, & Howard, 2005). The importance of this cartographic method is evident in the sheer volume of scholarly papers and books on thematic mapping that provide guidelines that inform both the theoretical and design components of making these types of maps for sighted map users. Research has focused on creating tactile map symbols and formalizing the techniques in tactile mapping, including the articulation of good practices (Tatham, 2003). However, the development and use of symbols for static tactile thematic maps has not been studied extensively. The lack of attention is not due to the absence of need, however; researchers and practitioners have expressed a clear need for the development of effective tactile thematic maps (Lobben, 2005). Even though thematic mapping has been a popular cartographic method for nearly 200 years, we cannot directly apply knowledge of the design of symbols for printed thematic maps as a guide for the creation of tactile symbols, given that it is often inappropriate to translate print map symbols into a tactile map format (James, 1982; Klatzky & Lederman, 1987). But, as we discuss later, several principles of cartographic design may be shared between the thematic design of tactile and visual symbols, such as max-contrast symbolization (Cromley, 2005; Dougenik & Sheehan, 1975; Gilmartin & Shelton, 1989), half-toning (Slocum, 1999), and nonlinear assumption (Kimerling, 1985). In the study presented here, we borrowed and applied these guidelines for making traditional print thematic maps to the design and subsequent evaluation of tactile thematic maps. A primary goal of the research was to identify effective symbols for tactile thematic maps. An effective symbology is based on discriminability and the extent to which the symbols foster spatial understanding. The two research questions that drove the experimental design and data analysis were these: 1. Can the tactile map user discriminate among the different fill patterns that are used to represent distinct classes of maps? 2. Can these symbols be used to create a classed quantitative choropleth tactile map that facilitates the recognition and overall understanding of spatial patterns, such as the population distribution of a state? Symbolization and use of tactile maps A critical area of research in tactile mapping involves the legibility and meaningfulness of tactile symbologies (Lambert & Lederman, 1989). The reading of tactile maps consists of a series of processes, beginning with the discrimination and identification of symbols (Perkins, 2002). Early studies of legibility included those on the effect of noise in detecting point symbols (Berla & Murr, 1975); minimum sizes for areal and point tactile symbols (Nolan & Morris, 1971); and the identification of one symbol among a series of symbols of the same class, either points, lines, or area (Barth, 1982). Barth, along with others (Gill & James, 1973; Lambert & Lederman, 1989), used a matching task or a paired comparison task in which a single symbol was identified among a set. These studies are relevant because they mimicked behavior that would be performed with a map legend. …

Abstract: Advantages of dasymetric map over traditional choropleth map have been well documented in many cartographic journals. Dasymetric uses ancillary dataset to create smaller geographical unit of population. In fact, the smaller geographical unit of population data is required for effective disaster management, emergency preparedness, retail market competition, health and disease studies, crime analysis and other population data analysis at micro-scale level. In this chapter, we discuss new dasymetric mapping technique based on GIS estimated building population which was computed from building footprints, census tract and LIDAR derived Digital Volume Model DVM.

Abstract: In recent years, geocomputational technologies hav e emerged as useful tools in diverse range of application traditionally catered for by soil surveys. These are used to record, store, manipulate and retrieve data from many soil observations including their location and elevation on the ground. The purpose of this study is to produce a digital soil map and to develop an interactive geodatabase with cropland s uitability analysis on the growth and production requirement of oil palm, cassava, and citrus in the study area. Also, to develop a choropleth map that is able to provide a visual view of all potential areas within the district study area where the selected crops can be grown. A geodatabase for crop land suitability analysis (Crop Mapper) was developed with the combination of ESRI ArcGIS and Microsoft SQL Server. The attribute data of the soils are effective depth, texture, drainage, pH, course fragments, slope, base saturation and climatic conditions such as rainfall, temperature and length of dry season. These attributes which were linked with spatial data to develop the soil geodatabase model, were considered as important criteria to determine the crop land suitability. The developed Crop Mapper has the ability to upload a soil map of the study area, perform spatial queries by attribute or using a query builder, and perfumes suitability analysis on three different soil series for three selected crops. Also, it is user friendly, fast and gives more accurate results.

Abstract: This paper presents possibilities of applying the geographically weighted regression method in mapping population change index. During the last decade, this contemporary spatial modeling method has been increasingly used in geographical analyses. On the example of the researched region of Timocka Krajina (defined for the needs of elaborating the Regional Spatial Plan), the possibilities for applying this method in disaggregation of traditional models of population density, which are created using the choropleth maps at the level of statistical spatial units, are shown. The applied method is based on the use of ancillary spatial predictors which are in correlation with a targeted variable, the population change index. For this purpose, spatial databases have been used such as digital terrain model, distances from the network of I and II category state roads, as well as soil sealing databases. Spatial model has been developed in the GIS software environment using commercial GIS applications, as well as open source GIS software. Population change indexes for the period 1961-2002 have been mapped based on population census data, while the data on planned population forecast have been used for the period 2002-2027.

Abstract: This small study evaluates the effectiveness of selected sets of colour schemes used in ESRI‟s ArcMap and ColorBrewer in communicating information on choropleth maps. Subjects conducted map reading tasks using online questionnaires and their performance was captured. The results did not show significant differences in performance associated with colour scheme - subjects were highly successful in direct acquisition tasks irrespective of the set(s) of scheme used. However, performances were consistently poor for „distribution‟ tasks. The results suggest limited spatial capabilities in the sample and highlight the need to test for general spatial ability in such experiments.

Abstract: This study aimed to inquire into possibilities of the web-based representation of thematic maps by geo-information mashup in the geoweb platform. In the Web2.0, Google platform leads the geoweb by offering effective mashup functions for geo-information. Geo-information mashup is opening a new horizon of map applications in fusion with a great of data in the Internet. Geo-information mashup by the available data method can be classified as two type; one is linkage of sources of platform 2011년 2월 7일 접수 Received on February 7, 2011 / 2011년 3월 18일 수정 Revised on March 18, 2011 / 2011년 3월 22일 심사완료 Accepted on March 22, 2011 * 본 논문은 2010년 5월 27-28일 대한지리학회 연례학술대회에서 발표한 내용을 수정·보완하여 투고한 것임. 1 전남대학교 지리교육과 Dept. of Geography Education, Chonnam National University 2 연변대학교, 지리학과 Dept. of Geogrpahy, Yanbian University, China ※ 연락저자 E-mail: jinsz@hanmail.net A Study on the Web-Based Representation of Thematic Maps Using GeoWeb Platform 108 itself(satellite images) and external data, the other is linkage of platform itself and user created contents. This study made heatmap, proportional map, and choropleth map based on Google satellite images by the linkage of platform itself and external data. As a result, thematic map of Google mashup expected to give us to a flexibility for difference interpretations of geographical distribution by representing overlap with satellite images.

Abstract: This study investigated the effectiveness of multivariate mapping in displaying functional relationships using a case example of social and political data from Bolivia. The effectiveness of four approaches to multivariate mapping (combined sequential schemes, separable graduated circles, choropleth/proportional symbols, and pair of sequential schemes) in communicating these relationships was evaluated. A paper map survey in English and Spanish was administered to thirty-four participants in the United States and thirty in Bolivia using four multivariate maps and one control (separate maps). Significant results showed that viewing the datasets displayed in separate maps best transmitted the map message. The pair of sequential schemes approach received the highest scores when considering the multivariate mapping methods only. This approach also yielded higher scores from the Bolivian sample, suggesting that readers lacking map experience can benefit from this form of multivariate mapping. Cultural differences revealed among the two sample groups shows that when creating a study using a map based evaluation, it is best to fully investigate cultural characteristics that surround map reading prior to creating the evaluation tool. While this study did reveal benefits of certain approaches to multivariate mapping, these approaches should be further investigated based on regional and characteristic differences among groups.

Abstract: Spatial variability in risk due to disease and mortality usually is displayed by choropleth maps. Often these maps are accompanied by displaying information if observed results are non‐randomly lower or larger than a threshold using classical statistical tests. In this work we study a statistical error which is seldom recognized when applying statistical tests: the Type III error. This kind of error may be undesirably large when the power of the statistical test is low.

Abstract: Background: Regionally partitioned health indicator values are commonly presented in choropleth maps. Policymakers and health authorities use them among others for health reporting, demand planning and quality assessment. Quite often there are concerns whether the health situation in certain areas can be considered different or equivalent to a reference value. Results: Highlighting statistically significant areas enables the statement that these areas differ from the reference value. However, this approach does not allow conclusions which areas are sufficiently close to the reference value, although these are crucial for health policy making as well. In order to overcome this weakness a combined integration of statistical difference and equivalence tests into choropleth maps is suggested and the approach is exemplified with health data of Austrian newborns. Conclusions: The suggested method will improve the interpretability of choropleth maps for policymakers and health authorities.

Abstract: In generating and exploring hypotheses, analysts often want to know about the relationship between data values across time and space. Often, the analysis begins at a world level view in which the overall temporal trend of the data is analyzed and linear correlations between various factors are explored. However, such an analysis often fails to take into account the underlying spatial structure within the data. In this work, we present an interactive visual analytics system for exploring temporal linear correlations across a variety of spatial aggregations. Users can interactively select temporal regions of interest within a calendar view window. The correlation coefficient between the selected time series is automatically calculated and the resultant value is displayed to the user. Simultaneously, a linked geospatial viewing window of the data provides information on the temporal linear correlations of the selected spatial aggregation level. Linear correlation values between time series are displayed as a choropleth map using a divergent color scheme. Furthermore, the statistical significance of each linear correlation value is calculated and regions in which the correlation value falls within the 95% confidence interval are highlighted. In this manner, analysts are able to explore both the global temporal linear correlations, as well as the underlying spatial factors that may be influencing the overall trend.

Abstract: We report on an empirical study investigating the effectiveness and efficiency of spatial inference making with contiguous (value-by-area) cartograms, compared to informational equivalent choropleth maps, combined with graduated circles. We find significant differences in people's inference-making performance dependent on the map type. Overall, results suggest that the choropleth map with graduated circles is more effective and more efficient than the cartogram for the analysis of population census data. However, map effectiveness and efficiency also significantly depends on the inference task complexity, and more surprisingly, on the shape characteristics of the depicted enumeration units. For simple tasks, cartograms seem as effective and efficient as the more traditional mapping method. For complex inference questions, inference performance with cartograms is significantly dependent on whether regular or irregular zones are distorted. As we know still very little about the perception and cognition of cartograms, we hope to shed new light for this intriguing mapping method with this empirical study.