​How to understand “absence of an arbitration agreement”

How to understand “absence of an arbitration agreement”
An arbitration agreement may be a separate written agreement referring to a master contract or an arbitration clause contained in a contract. And such an arbitration agreement may be executed either before or after the occurrence of a dispute between the parties.
Therefore, they may enter into a written arbitration agreement before referring to arbitration, or the claimant has to file a request for arbitration accompanied by an arbitration agreement. If the request for arbitration is not accompanied by an arbitration agreement or the arbitration agreement submitted is held invalid, the request for arbitration will not be accepted or will be dismissed after acceptance.
For example, an arbitration agreement will be held invalid if the dispute involves personal or marital issues or should be resolved by an administrative authority, or it is agreed therein that the dispute may be referred to arbitration or submitted to a competent court, or no arbitration institute is specified therein.