"We asked them to hang out around our parked cars," a company spokesperson wrote in the company's monthly newsletter that details the latest from its self-driving car project. "This gives our sensors and software extra practice at recognizing children in all their unique shapes and sizes, even when they're in odd costumes."
With its Halloween research, the company both refined the software's ability to discern its ability to detect kids and added to a knowledge base that includes thousands and thousands of variations of similar conduct. Costumes can alter those scenarios and can cause children to move differently, so though the number of Halloween scenarios are small, they're valuable.
Google says its autonomous cars, which now number 48, drive more cautiously around children because their software is programmed to anticipate unpredictable movements, like suddenly darting across a street or running out from behind a parked car. In a world of human drivers, those circumstances are difficult for motorists to anticipate.
Kids are particularly vulnerable on Halloween. An average of almost 30 pedestrians are annually killed each October 31, according to National Highway Traffic Safety Administration figures. That's almost triple the number of pedestrian deaths that occur during an average day on American roads.
Overall, Halloween ranks as the third-deadliest day on the calendar for pedestrians, according to NHTSA, which examined a quarter-century's worth of data to determine which days are most dangerous for pedestrians. New Year's Day is historically the day most pedestrian deaths occur, followed by Dec. 23.