Data Errors Skew LA Crime Map

An article in today’s Los Angeles Times uses a geocoding error in the LAPD’s crime map mashup to illustrate the perils of map data error. In the case of the LAPD’s map, crimes at addresses that could not be parsed defaulted to the centre of the city, giving that particular neighbourhood a disproportionately high crime rate. Given the number of mashups and online applications in which “an algorithm tries to translate unruly street addresses, often drawn from handwritten forms, into the precision of decimal degrees,” this article is a cautionary tale. Via CNet, MapHist and Slashdot.