TY - GEN

T1 - Separating the communication complexity of truthful and non-truthful combinatorial auctions

AU - Assadi, Sepehr

AU - Khandeparkar, Hrishikesh

AU - Saxena, Raghuvansh R.

AU - Weinberg, S. Matthew

PY - 2020/6/8

Y1 - 2020/6/8

N2 - We prove the first separation in the approximation guarantee achievable by truthful and non-truthful combinatorial auctions with polynomial communication. Specifically, we prove that any truthful auction guaranteeing a (34-1240+")-approximation for two buyers with XOS valuations over m items requires exp(ω(ϵ2 · m)) communication whereas a non-truthful auction by Feige [J. Comput. 2009] is already known to achieve a 34-approximation in (m) communication. We obtain our lower bound for truthful auctions by proving that any simultaneous auction (not necessarily truthful) which guarantees a (34-1240+ϵ)-approximation requires communication exp(ω(ϵ2 · m)), and then apply the taxation complexity framework of Dobzinski [FOCS 2016] to extend the lower bound to all truthful auctions (including interactive truthful auctions).

AB - We prove the first separation in the approximation guarantee achievable by truthful and non-truthful combinatorial auctions with polynomial communication. Specifically, we prove that any truthful auction guaranteeing a (34-1240+")-approximation for two buyers with XOS valuations over m items requires exp(ω(ϵ2 · m)) communication whereas a non-truthful auction by Feige [J. Comput. 2009] is already known to achieve a 34-approximation in (m) communication. We obtain our lower bound for truthful auctions by proving that any simultaneous auction (not necessarily truthful) which guarantees a (34-1240+ϵ)-approximation requires communication exp(ω(ϵ2 · m)), and then apply the taxation complexity framework of Dobzinski [FOCS 2016] to extend the lower bound to all truthful auctions (including interactive truthful auctions).

KW - Combinatorial Auctions

KW - Lower Bounds

KW - Simultaneous Communication

UR - http://www.scopus.com/inward/record.url?scp=85086757472&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=85086757472&partnerID=8YFLogxK

U2 - 10.1145/3357713.3384267

DO - 10.1145/3357713.3384267

M3 - Conference contribution

AN - SCOPUS:85086757472

T3 - Proceedings of the Annual ACM Symposium on Theory of Computing

SP - 1073

EP - 1085

BT - STOC 2020 - Proceedings of the 52nd Annual ACM SIGACT Symposium on Theory of Computing

A2 - Makarychev, Konstantin

A2 - Makarychev, Yury

A2 - Tulsiani, Madhur

A2 - Kamath, Gautam

A2 - Chuzhoy, Julia

PB - Association for Computing Machinery

T2 - 52nd Annual ACM SIGACT Symposium on Theory of Computing, STOC 2020

Y2 - 22 June 2020 through 26 June 2020

ER -