BEGIN:VCALENDAR
VERSION:2.0
PRODID:-//talks.cam.ac.uk//v3//EN
BEGIN:VTIMEZONE
TZID:Europe/London
BEGIN:DAYLIGHT
TZOFFSETFROM:+0000
TZOFFSETTO:+0100
TZNAME:BST
DTSTART:19700329T010000
RRULE:FREQ=YEARLY;BYMONTH=3;BYDAY=-1SU
END:DAYLIGHT
BEGIN:STANDARD
TZOFFSETFROM:+0100
TZOFFSETTO:+0000
TZNAME:GMT
DTSTART:19701025T020000
RRULE:FREQ=YEARLY;BYMONTH=10;BYDAY=-1SU
END:STANDARD
END:VTIMEZONE
BEGIN:VEVENT
CATEGORIES:Isaac Newton Institute Seminar Series
SUMMARY:A quantitative version of the Gibbard-Satterthwait
 e theorem - Kindler\, G (HUJI)
DTSTART;TZID=Europe/London:20110401T113000
DTEND;TZID=Europe/London:20110401T123000
UID:TALK30513AThttp://talks.cam.ac.uk
URL:http://talks.cam.ac.uk/talk/index/30513
DESCRIPTION:Consider an election between q alternatives\, wher
 e each of the voters rank the different alternativ
 es\, and the winner is determined according to som
 e predefined function of this voting profile. Such
  a social choice function is called manipulable\, 
 if a situation might occur where a voter who knows
  the rankings given by other voters can change her
  ranking in a way that does not reflect her true p
 reference\, but which leads to an outcome that is 
 more desirable to her. \n\nGibbard and Satterthwai
 te proved that any social choice function where mo
 re than two alternatives can be selected is manipu
 lable\, unless it is a dictatorship (where the out
 come of the election only depends on the choices o
 f one voter). In the case where the social choice 
 function is neutral\, namely when it is invariant 
 under changing the names of the alternatives\, we 
 prove a lower bound on the fraction of manipulable
  preference profiles which is inverse polynomial i
 n the number of voters and alternatives. Our proof
  in fact does not rely on discrete harmonic analys
 is - finding an analytic version of the proof woul
 d be the role of the audience. \n\nJoint work with
  Marcus Isaksson and Elchanan Mossel.\n
LOCATION:Seminar Room 1\, Newton Institute
CONTACT:Mustapha Amrani
END:VEVENT
END:VCALENDAR