Parsing schemata are high-level descriptions of parsing algorithms. This paper is concerned with parsing schemata for different grammar formalisms. We separate the description of parsing steps from that of grammatical properties by means of abstract parsing schemata. We define an abstract Earley schema and prove it correct. We obtain Earley schemata for several grammar formalisms by specifying the grammatical properties in the abstract Earley schema. Our approach offers a clear and well-defined ...