Event-response systems: a technique for specifying multi-threaded dialogues

Event-Response Systems are a technique for specifying the syntax of multi-threaded dialogues. They are based on the paradigm of specifying system responses to events generated by the user. They can compactly represent the concurrency needed to implement multi-threaded dialogues. This concurrency support also allows interfaces to be structured differently than is possible with existing dialogue specification systems based on state transition specifications or grammars. This flexibility allows many interfaces, especially direct manipulation interfaces, to be specified with a more modular structure than most existing systems allow.Event-Response Systems are described formally, and a dialogue specification language based on the ERS formalism is informally presented. Some example uses and implementation techniques are also described.