While there's been an informal coterie of R users in the Chicago area for some time (notably the fine folks behind the successful R/Finance conferences) there hasn't been a formal R User Group. Until now, that is. JD Long has taken the plunge and announced the new Chicago R User Group on meetup.com. If you're in the Chicagoland area, why not sign up?
MeetUp.com: Chicago R User Group
Comments