B O S T O N   U N I V E R S I T Y
                      Computer Science Department
                          C O L L O Q U I U M
				and
	  		A Guest Lecture for CS-237 

                   Wednesday, September 13, 10:30 AM
                      (Coffee served at 10:15 AM)
                        Seminar Room / MCS 135


                            Rohit Parikh

               Computer Science, Mathematics, Philosophy
               Brooklyn College and CUNY Graduate Center

                    Some Puzzles about Probability

Probability theory, which is a basis for decision theory has always been 
plagued by paradoxes, ever since the St. Petersburg paradox of the 18th 
century. There have been many interesting paradoxes since then.
Some are paradoxes only because people seem to act in an "irrational"
way. Some are paradoxes because the problem makes unrealistic mathematical 
assumptions. And some actually do appear to be paradoxes.

Thus, can I know something about the color of my hat merely by seeing the 
hats that others are wearing, even when all colors are chosen randomly and 
independently?

Can two people both get richer by exchanging envelopes that they are holding?

Can a drug be good for men and good for women but bad for adults?

Answering such questions can amuse as well as sharpen our intuitions.

Host: L. Levin
===========================

Rohit Parikh holds degrees from Harvard in Physics and Mathematics.
He is a three times winner in the Putnam mathematical competition.
He is currently a distinguished professor at the City University of New York, 
but previously, in addition to Stanford, Bristol, SUNY, and NYU, he has also 
taught for fifteen years at Boston University. His interests have included 
formal languages, non-standard analysis, dynamic logic, logic of knowledge, 
and most recently social software, which he originated and which has been the 
subject of two European conferences.