%0 Journal Article %T Improving Man-Optimal Stable Matchings by Minimum Change of Preference Lists %A Takao Inoshita %A Robert W. Irving %A Kazuo Iwama %A Shuichi Miyazaki %A Takashi Nagase %J Algorithms %D 2013 %I MDPI AG %R 10.3390/a6020371 %X In the stable marriage problem, any instance admits the so-called man-optimal stable matching, in which every man is assigned the best possible partner. However, there are instances for which all men receive low-ranked partners even in the man-optimal stable matching. In this paper we consider the problem of improving the man-optimal stable matching by changing only one man¡¯s preference list. We show that the optimization variant and the decision variant of this problem can be solved in time O( n 3) and O( n 2), respectively, where n is the number of men (women) in an input. We further extend the problem so that we are allowed to change k men¡¯s preference lists. We show that the problem is W[1]-hard with respect to the parameter k and give O( n 2k+1)-time and O( n k+1)-time exact algorithms for the optimization and decision variants, respectively. Finally, we show that the problems become easy when k = n; we give O( n2.5 log n)-time and O( n 2)-time algorithms for the optimization and decision variants, respectively. %K combinatorial optimization %K polynomial-time algorithms %K stable marriage problem %K man-optimal stable matching %U http://www.mdpi.com/1999-4893/6/2/371