Privacy protections included obscuring start and end points of trips as well as letting people manage their travel data online.
The pilot project has been going on for about five months.
"The predictive capabilities are head and shoulders above what exists today," Day said. "Everything out there is showing you traffic as reported five or 10 minutes ago. Nobody does predictive."
While testing is in California, IBM is intent on building a system that can work around the world.
"Unlike existing traffic alert solutions, we're helping take the guesswork out of commuting," said Stefan Nusser of IBM Almaden Services Research.
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