People change as we know, as time passes, as they grow, as they face various situations in their life. Even wizards are basically people like muggles except for magic.
Say a student is intelligent so sorting hat puts him/her in Ravenclaw. But later on the student starts displaying bravery. This new trait starts overpowering his/her intelligence. So can the student switch to Gryffindor by himself, obviously after getting permissions and approvals of higher authority.
Basically, can students in Hogwarts change their house after official sorting has been done by sorting hat?