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Forecasting Hotspots—A Predictive Analytics Approach
April 2011 (vol. 17 no. 4)
pp. 440-453
Ross Maciejewski, Purdue University, West Lafayette
Ryan Hafen, Purdue University, West Lafayette
Stephen Rudolph, Purdue University, West Lafayette
Stephen G. Larew, Purdue University, West Lafayette
Michael A. Mitchell, Purdue University, West Lafayette
William S. Cleveland, Purdue University, West Lafayette
David S. Ebert, Purdue University, West Lafayette
Current visual analytics systems provide users with the means to explore trends in their data. Linked views and interactive displays provide insight into correlations among people, events, and places in space and time. Analysts search for events of interest through statistical tools linked to visual displays, drill down into the data, and form hypotheses based upon the available information. However, current systems stop short of predicting events. In spatiotemporal data, analysts are searching for regions of space and time with unusually high incidences of events (hotspots). In the cases where hotspots are found, analysts would like to predict how these regions may grow in order to plan resource allocation and preventative measures. Furthermore, analysts would also like to predict where future hotspots may occur. To facilitate such forecasting, we have created a predictive visual analytics toolkit that provides analysts with linked spatiotemporal and statistical analytic views. Our system models spatiotemporal events through the combination of kernel density estimation for event distribution and seasonal trend decomposition by loess smoothing for temporal predictions. We provide analysts with estimates of error in our modeling, along with spatial and temporal alerts to indicate the occurrence of statistically significant hotspots. Spatial data are distributed based on a modeling of previous event locations, thereby maintaining a temporal coherence with past events. Such tools allow analysts to perform real-time hypothesis testing, plan intervention strategies, and allocate resources to correspond to perceived threats.

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Index Terms:
Predictive analytics, visual analytics, syndromic surveillance.
Ross Maciejewski, Ryan Hafen, Stephen Rudolph, Stephen G. Larew, Michael A. Mitchell, William S. Cleveland, David S. Ebert, "Forecasting Hotspots—A Predictive Analytics Approach," IEEE Transactions on Visualization and Computer Graphics, vol. 17, no. 4, pp. 440-453, April 2011, doi:10.1109/TVCG.2010.82
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