In Philip K. Dick's story (and the Tom Cruise film), mutants with precognitive abilities predict that someone will commit a crime, so the police can arrest them and prevent them from committing the crime.
In the real world, a computer program uses an algorithm to predict crime. Police in Santa Cruz, California are actually using it to prevent burglaries and car break-ins.
The heart of the program is the belief that criminals often commit a second or third crime in the same location and the same time as a first successful crime. For example, if a burglar is successful breaking into a home at 2 p.m. in a certain neighborhood because no
one is home, the criminal will use that experience to do it again to another house in the same neighborhood around the same time.
In the case of Santa Cruz, on California’s central coast and home to a University of California campus, that would be about four days later.
The algorithm knows this because Mohler has fed eight years of data on crimes in Santa Cruz into the algorithm.