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The need to provide effective tools for analyzing and querying spatial data is becoming increasingly important with the explosion of data in applications such as Geographic Information Systems Image Databases CAD and Remote Sensing The SEE (Spatial Exploration System) is the first effort of apply- ing direct-manipulation visual information seeking (VIS) techniques to spatial data analysis by visually querying as well as browsing spatial data and reviewing the visual results for trend analysis The SEE system incorporates a visual query language (SVIQUEL) which allows users to specify the relative spa- tial position (both topology and direction) between objects using direct manipulation The quantitative SVIQUEL sliders (S-sliders) are complemented by the qualitative Active-Picture-for-Querying (APIQ) which allows the user to specify qualitative relative position queries APIQ provides qualitative visual representations of the quantitative query specified by the S-sliders This increases the utility of the system for spatial browsing and spatial trend discovery with no particular query in mind The queries are processed using a k-Bucket index structure specifically tuned for incremental processing of multi- dimensional range queries We have also designed a map visualization which helps preserve the spatial context and a bar visualization that provides a qualitative abstraction of aggregates and enable the user to visualize the results of the spatial query as well as the non-spatial attributes of the underlying spatial objects This system has been fully implemented as an applet using JDK1 1 4 Finally we also evaluated our spatial exploration environment (SEE) technology with respect to its querying power and the ease of querying