The arbitration committee shall not be bound by common law or statutory rules of evidence or by technical or formal rules of procedure but may make such investigation or inquiry and conduct its hearing in such manner as it deems proper and necessary in the premises. The claimant physician may present his case, call his witnesses, present his proofs and submit to questions thereon. The defending carrier may present its defense, call its witnesses, present its proofs and submit to questions thereon. The arbitration committee may, in the event of nonappearance, decide the value of the disputed medical bill on the basis of the evidence before it. The majority decision of such a committee shall be conclusive upon the parties as to the value of the services rendered.