We are developing several exercise assistants which give very good feedback. To develop an exercise assistant, we need three components: a domain description, rules for reasoning about the domain, and one or more strategies for solving the exercises in the domain. To support the possibility to adapt the several components, to avoid code duplication and maximize code reuse, we have developed a g...

This article examines the influence of teacher assistants and other personnel on outcomes for elementary school students during a period recession-induced cutbacks in assistants. Using panel data from North Carolina, we exploit state’s unique system financing its local public schools to identify causal effects assistants, controlling staff, measures student achievement. We find consistent evide...

The Medicare rules governing the supervision of diagnostic tests have changed over time, as have the skills and training of radiologist assistants, who may have the education and clinical skills to deliver surgical and invasive procedures often performed as part of a radiology practice. However, for the purposes of Medicare coverage, radiologist assistants are not yet recognized as independent ...

The telecommunications environment that will exist in the near future will consist of a complex web of interacting devices and services. Users will need help in dealing successfully and productively with this environment, which will be made more complex by their own mobility. They will need on-line software systems that can represent them in their absence, represent them in routine or mundane i...