1. A method for adjusting a contention window size (CWS) in a wireless access system, the method comprising:performing a channel access procedure;
transmitting, in a plurality of time durations, a transmission burst based on the channel access procedure;
obtaining hybrid automatic repeat and request acknowledgment (HARQ-ACK) information related to the transmission burst; and
adjusting the CWS based on counting at least one value of HARQ-ACK information related to a starting time duration included in the plurality of the time durations,
wherein the at least one value of the HARQ-ACK information is counted based on whether a part of the transmission burst in the starting time duration is scheduled by a self-carrier scheduling or a cross-carrier scheduling.