In a communication system, a transmitter device transmits data to a receiver device for performing error-correcting decoding processing by combining received data and retransmitted data. The transmitter device selects one of a first set of schemes of an M number of modulation and coding schemes as a modulation and coding scheme (MCS) of first data according to communication quality information obtained from the receiver device when the first data is initially transmitted, and selects one of a second set of schemes of an N number of MCSs (N