MarkLogic Server 4.0 Geospatial Range Demo

This demo uses the optional geospatial analytics capabilities introduced in MarkLogic Server 4.0 to produce an interactive visualization of how campaign issues related to geography during the first half of the 2008 U.S. presidential campaign.

The database behind this demo contains more than seven thousand entries from political blogs. MarkLogic Server 4.0's optional entity extraction capability has been used to identify and mark up any place names mentioned in the blog entries. Once identified, an XQuery program correlated the the XML inline entities against a commonly available gazetteer in order to generate matching longitude and latitude information. A geospatial attribute pair lexicon was then configured on the resulting enhanced entities.

In the demo, you can specify a simple keyword search (for instance, try any of the terms "obama", "clinton", "gas tax", "amnesty" or "mormon"), which filters the blog entries in the database into a result set on which real-time geospatial analytics are performed. You are then presented with:

a list of the most relevant entries (with titles and introductory content displayed) based on relevance to the search term(s) provided; each title acts as a link to the original online blog entry
a geospatial heatmap tool, which visualizes the frequency with which various parts of the world are mentioned in the entries in the result set

The heatmap tool can be used to further explore and filter the result set, as follows:

Clicking on the zooming bar will allow you to zoom further in or out of the displayed map. Results will be automatically filtered to include only those entries including a mention of a location within the displayed map area.
Click-dragging within the map will allow you to scroll the map north, south, east or west. Releasing the mouse will cause the map to be redrawn, and results will be automatically filtered to include only those entries including a mention of a location within the displayed map area.
Control-clicking on a heatmap tile will zoom in to make that tile the viewable area in the heatmap tool, and results will be automatically filtered to include only those entries including a mention of a location within the displayed map area.
Adjusting the X and Y sliders at the bottom left of the tool will change the number (and size) of the tiles used for generating the heatmaps.

Select a query to start the demo:

Notes

This demo is running on a commodity Linux server with 2 dual-core x64 chips and 8 GB of RAM. The server is a shared resource that supports multiple demos simultaneously. The visualization tool runs in Flex and requires that Adobe Flash Player 9 (version 124 or later) be installed. To update your Flash Player, go to http://www.adobe.com/go/getflashplayer.

The complete source code for this demo is provided in the Samples/heatmaps directory of the MarkLogic Server 4.0 release package. Information about its use can be found in Samples/samples-license.txt.

Note: this site is provided for demonstration purposes only. The content behind it runs through mid-June of the presidential campaign, and is not kept up to date. Content remains the property of the originating web sites, to which you are linked should you wish to read the complete entries.