2009 General Offense Frequency

Salt Lake City

The "Data Rose" shows ten crime types in Salt Lake City changing over time and space. Each sector represents a single crime type. The rings represent a monthly frequency, with January in the center and December on the outer edge.

The color of each band shows the number of occurrences for a given crime for that month. Note that the color ramp is consistent within a given crime type, but not between different types. There are five frequency classes per crime type, so while green always indicates at least a single crime for the lower bounds, red can vary widely. For "Sex Assaults," red shows five to six occurrences for that month, but with "Car Prowls," red indicates sixty-five to 135 occurrences.

This method to display data over space and time was inspired by the work of Guilan Huang of Georgetown University. Huang applied rings around an entire county, with each sector showing a single variable through time for a given ZIP Code. Here, the approach was modified to shrink the rings within the area of interest and convert the sectors to show ten variables rather than one.

This would be an effective way to display other data, such as bird sighting frequency for different areas, with the sectors being species rather than crime types, or water-quality variables.

Courtesy of Salt Lake City Corp.

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