premise: Fat Mattress were an English folk rock band that formed in Folkestone in 1968. Founded by guitarist and vocalist Noel Redding, during his time as bassist for The Jimi Hendrix Experience, and vocalist Neil Landon, the band was completed by multi-instrumentalist Jim Leverton and drummer Eric Dillon. The band released two albums – "Fat Mattress" and "Fat Mattress II" – before splitting up in 1970.
hypothesis: Fat Mattress formed in the year after 1966.
reason: Fat Mattress formed in 1968. The system was confused by the year.