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Necklace Maps
November/December 2010 (vol. 16 no. 6)
pp. 881-889
ASCII Text
x 
 
Bettina Speckmann, Kevin Verbeek, "Necklace Maps," IEEE Transactions on Visualization and Computer Graphics, vol. 16, no. 6, pp. 881-889, November/December, 2010.
 
 
BibTex
x
 
@article{ 10.1109/TVCG.2010.180,
author = {Bettina Speckmann and Kevin Verbeek},
title = {Necklace Maps},
journal ={IEEE Transactions on Visualization and Computer Graphics},
volume = {16},
number = {6},
issn = {1077-2626},
year = {2010},
pages = {881-889},
doi = {http://doi.ieeecomputersociety.org/10.1109/TVCG.2010.180},
publisher = {IEEE Computer Society},
address = {Los Alamitos, CA, USA},
}
 
 
RefWorks Procite/RefMan/Endnote
x 
 
TY - JOUR
JO - IEEE Transactions on Visualization and Computer Graphics
TI - Necklace Maps
IS - 6
SN - 1077-2626
SP881
EP889
EPD - 881-889
A1 - Bettina Speckmann,
A1 - Kevin Verbeek,
PY - 2010
KW - Geographic Visualization
KW - Automated Cartography
KW - Proportional Symbol Maps
KW - Necklace Maps
VL - 16
JA - IEEE Transactions on Visualization and Computer Graphics
ER -
 
Statistical data associated with geographic regions is nowadays globally available in large amounts and hence automated methods to visually display these data are in high demand. There are several well-established thematic map types for quantitative data on the ratio-scale associated with regions: choropleth maps, cartograms, and proportional symbol maps. However, all these maps suffer from limitations, especially if large data values are associated with small regions. To overcome these limitations, we propose a novel type of quantitative thematic map, the necklace map. In a necklace map, the regions of the underlying two-dimensional map are projected onto intervals on a one-dimensional curve (the necklace) that surrounds the map regions. Symbols are scaled such that their area corresponds to the data of their region and placed without overlap inside the corresponding interval on the necklace. Necklace maps appear clear and uncluttered and allow for comparatively large symbol sizes. They visualize data sets well which are not proportional to region sizes. The linear ordering of the symbols along the necklace facilitates an easy comparison of symbol sizes. One map can contain several nested or disjoint necklaces to visualize clustered data. The advantages of necklace maps come at a price: the association between a symbol and its region is weaker than with other types of maps. Interactivity can help to strengthen this association if necessary. We present an automated approach to generate necklace maps which allows the user to interactively control the final symbol placement. We validate our approach with experiments using various data sets and maps.

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Index Terms:
Geographic Visualization, Automated Cartography, Proportional Symbol Maps, Necklace Maps
Citation:
Bettina Speckmann, Kevin Verbeek, "Necklace Maps," IEEE Transactions on Visualization and Computer Graphics, vol. 16, no. 6, pp. 881-889, Nov.-Dec. 2010, doi:10.1109/TVCG.2010.180
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