The acquisition of planning knowledge

Two studies have incorporated the use of the Problem Solving Environment (PSE) in their design. One was the second experiment of chapter 7, which contrasted learning from abstract and specific instruction. As the final part of that study, one group of students worked for one session with PSE while another group completed the original SPS instruction. The essential conclusion we drew from the study was that 1 hour was simply too brief a time for the students to become comfortable in the interactive environment. They were able to use PSE but not as freely as we had hoped, and we suspected that their freedom to develop their own plans for problem solving was hampered by a lack of familiarity with the computer system itself. 

The study to be described here is not an experiment in the usual sense. For the most part, it is a qualitative, rather than a quantitative, study. There are no statistical hypotheses to be tested and no parameters to be estimated. Instead, the focus is on delineating individual behavior. Some aggregation of data has been done, but the primary intent is to describe in detail individual performances in PSE. 

Subjects were 17 students drawn from the same population as those who participated in the studies described in chapter 7 ( i.e., college students who demonstrated poor problem-solving skills). 

Each student took part in three instructional sessions. In the first session, they were presented with a condensed version of the original SPS instruction. The session lasted a full hour (in contrast to the 45-50 min of the studies described in chapter 7), and students worked through the introductory lesson and task, completed the mapping instruction and tasks, and began the instruction about multistep problems and planning all in one session. Some of the students completed the planning instruction on the first day. Those who did not finish the entire sequence in one session completed it in 5-10 min at the start of the second session. 

The second and third sessions were devoted to use of the PSE. In the second session, each student was given an introduction to the system by the experimenter and allowed to explore and investigate the various options available. Most of the students worked on one to three problems, but many did not make any systematic efforts to solve them. 

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The purpose of this chapter is to review the practical aspects of state-of-the-art lower-extremity CTA in its role as a treatment-planning tool for patients with PAOD. Taking full advantage of the capabilities of lower-extremity CTA in this role requires integration of acquisition and contrast medium injection parameters, with knowledge of therapeutic options and the ability to vi-... 

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