Resolution Control for Balancing Overview and Detail in Multivariate Spatial Analysis

Abstract

Parallel coordinates, re-orderable matrices, and dendrograms, widely used methods for visual exploration of multivariate data, are systematically integrated in a complementary manner for supporting multi-resolution visual data analysis with an enhanced overview + detail exploratory strategy. There are three main topics: (1) dynamic control across resolutions at which data are explored; (2) coordination and color mapping among the views; and (3) enhanced features of each view designed for the overview + detail exploratory tasks. A case study analysis is used to demonstrate the potential for boosting productivity for exploration tasks by coordinating the views through user-controlled resolutions within a highly interactive analysis environment. The case study is focused on a complex, geographically referenced dataset including public health, demographic and environmental components.     

Topological Coordinates: Numerically Encoding the Underlying Topological Structure of Plane Graphs

A new methodology is presented for the concise numerical encoding of a map's topological structure based on several surprising and beautifully intertwined graph decomposition results due to Walter Schnyder. Not only are Schnyder's methods used to determine new positions for a graph's vertices, a map's topological connectivity information is also simultaneously implicitly stored and recovered by folding information about the edge structure of its embedded line-segment graph into numerical topology-based barycentric coordinates chosen for the graph's vertices. Properties of the alternative geometric realization are explored and shown to permit cartogram construction by systematically altering the topological coordinates to modify the regions' relative areas.     

Report on Cartographic and GIS Activity in the U.S. Fish and Wildlife Service

The U.S. Fish and Wildlife Service (FWS) is a federal agency whose mission is, working with others, to conserve fish and wildlife and their habitats for the continuing benefit of the American people. Under the management of fish and wildlife professionals, the National Wildlife Refuge System has become the world's premier network of wildlife habitats. The FWS is making use of modern cartographic methods and implementing Geographic Information Systems to more effectively manage the lands and resources entrusted to them.