Five-card majors for offensive purposes. However, if the trump cards break 4-1 or 1-4, then drawing trump will result in no trumps left for offensive purposes. The value of five-card majors can be understood then on two levels: But five-card majors have several drawbacks: Both partners must agree to follow the five-card major bidding treatment on their opening bid. Opener must have at least five cards in hearts or spades to start the bidding with that suit. Responder is expected to show support with three-card support, indicating an eight-card fit. With only four cards in a major suit, the opening bidder is
Jump bidding will always win the item for free. Such cooperation could be very beneficial to both bidders in the long run. The problem is, it cannot be enforced, because both bidders have an incentive to say that their value is higher than it really is. Here jump-bidding comes into play. It works like a signaling game. By jump-bidding, the jumper signals that he has a high value, and so the other bidder should quit immediately if his value is lower. Two bidders, Xenia and Yakov, participate in an auction for a single item. This is a common value auction with the