Human Tutorial Instruction in the Raw

Humans learn procedures from one another through a variety of methods, such as observing someone do the task, practicing by themselves, reading manuals or textbooks, or getting instruction from a teacher. Some of these methods generate examples that require the learner to generalize appropriately. When procedures are complex, however, it becomes unmanageable to induce the procedures from examples alone. An alternative and very common method for teaching procedures is tutorial instruction, where a teacher describes in general terms what actions to perform and possibly includes explanations of the rationale for the actions. This article provides an overview of the challenges in using human tutorial instruction for teaching procedures to computers. First, procedures can be very complex and can involve many different types of interrelated information, including (1) situating the instruction in the context of relevant objects and their properties, (2) describing the steps involved, (3) specifying the organization of the procedure in terms of relationships among steps and substeps, and (4) conveying control structures. Second, human tutorial instruction is naturally plagued with omissions, oversights, unintentional inconsistencies, errors, and simply poor design. The article presents a survey of work from the literature that highlights the nature of these challenges and illustrates them with numerous examples of instruction in many domains. Major research challenges in this area are highlighted, including the difficulty of the learning task when procedures are complex, the need to overcome omissions and errors in the instruction, the design of a natural user interface to specify procedures, the management of the interaction of a human with a learning system, and the combination of tutorial instruction with other teaching modalities.