Jeff Jarvis is likely to sleep between 11 p.m. and 6 a.m.
Jeff Jarvis - @BuzzMachine blogger and j-school prof; author of Public Parts, What Would Google Do?
Jeff Jarvis is located in New York, NY (Eastern Time (US & Canada) time zone). If the sleeping schedule doesn't appear right, maybe @jeffjarvis hasn't specified the correct timezone in their Twitter profile.
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