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Materializing Spatial Correlation<br />

■ The ODM engine processes materialized data (spatial and nonspatial) to generate<br />

mining results.<br />

The following are examples of the kinds of data mining applications that could benefit<br />

from including spatial information in their processing:<br />

■ Business prospecting: Determine if colocation of a business with another franchise<br />

(such as colocation of a Pizza Hut restaurant with a Blockbuster video store) might<br />

improve its sales.<br />

■ Store prospecting: Find a good store location that is within 50 miles of a major city<br />

and inside a state with no sales tax. (Although 50 miles is probably too far to drive<br />

to avoid a sales tax, many customers may live near the edge of the 50-mile radius<br />

and thus be near the state with no sales tax.)<br />

■ Hospital prospecting: Identify the best locations for opening new hospitals based<br />

on the population of patients who live in each neighborhood.<br />

■ Spatial region-based classification or personalization: Determine if southeastern<br />

United States customers in a certain age or income category are more likely to<br />

prefer "soft" or "hard" rock music.<br />

■ Automobile insurance: Given a customer’s home or work location, determine if it<br />

is in an area with high or low rates of accident claims or auto thefts.<br />

■ Property analysis: Use colocation rules to find hidden associations between<br />

proximity to a highway and either the price of a house or the sales volume of a<br />

store.<br />

■ Property assessment: In assessing the value of a house, examine the values of<br />

similar houses in a neighborhood, and derive an estimate based on variations and<br />

spatial correlation.<br />

8.2 Spatial Binning for Detection of Regional Patterns<br />

Spatial binning (spatial discretization) discretizes the location values into a small<br />

number of groups associated with geographical areas. The assignment of a location to<br />

a group can be done by any of the following methods:<br />

■ Reverse geocoding the longitude/latitude coordinates to obtain an address that<br />

specifies (for United States locations) the ZIP code, city, state, and country<br />

■ Checking a spatial bin table to determine which bin this specific location belongs<br />

in<br />

You can then apply ODM techniques to the discretized locations to identify interesting<br />

regional patterns or association rules. For example, you might discover that customers<br />

in area A prefer regular soda, while customers in area B prefer diet soda.<br />

The following functions and procedures, documented in Chapter 29, perform<br />

operations related to spatial binning:<br />

■ SDO_SAM.BIN_GEOMETRY<br />

■ SDO_SAM.BIN_LAYER<br />

8.3 Materializing Spatial Correlation<br />

Spatial correlation (or, neighborhood influence) refers to the phenomenon of the location<br />

of a specific object in an area affecting some nonspatial attribute of the object. For<br />

example, the value (nonspatial attribute) of a house at a given address (geocoded to<br />

Spatial Analysis and Mining 8-3

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