If it’s Tuesday, this must be . . . Massachusetts.

Mayor Bloomberg flew to Cambridge, Mass., yesterday to deliver the keynote address at the MIT Collaborative Initiative Conference, which describes itself on its Web site as dedicated to “a systems-based approach to solving deep-rooted social problems.”

On Monday, the mayor attended the funeral in Chicago of Margaret Daley, wife of former Chicago Mayor Richard Daley.

The mayor’s back-to-back out-of-town trips didn’t cause much of a stir around City Hall.

“In the days of horses, I think it mattered more,” said Councilman Lew Fidler (D-Brooklyn).