We evaluate the “story grammar” approach to story understanding from three perspectives. We first examine the formal properties of the grammars and find only one to be formally adequate. We next evaluate the grammars empirically by asking whether they generate all simple stories and whether they generate only stories. We find many stories that they do not generate and one major class of nonstory that they do generate. We also evaluate the grammars' potential as comprehension models and find that they (...) would add nothing to semantic models that focus on the story content. Hence we advocate a story content oriented approach to studying story understanding instead of the structural story grammar approach. (shrink)

Biological phenomena can be investigated at multiple levels, from the molecular to the cellular to the organismic to the ecological. In typical biology instruction, these levels have been segregated. Yet, it is by examining the connections between such levels that many phenomena in biology, and complex systems in general, are best explained. We describe a computation-based approach that enables students to investigate the connections between different biological levels. Using agent-based, embodied modeling tools, students model the microrules underlying a biological phenomenon (...) and observe the resultant aggregate dynamics. We describe 2 cases in which this approach was used. In both cases, students framed hypotheses, constructed multiagent models that incorporate these hypotheses, and tested these by running their models and observing the outcomes. Contrasting these cases against traditionally used, classical equation-based approaches, we argue that the embodied modeling approach connects more directly to students’ experience, enables extended investigations as well as deeper understanding, and enables “advanced” topics to be productively introduced into the high school curriculum. (shrink)

This paper is concerned with those elements of planning knowledge that are common to both understanding someone else's plan and creating a plan for one's own use. This planning knowledge can be divided into two bodies: Knowledge about the world, and knowledge about the planning process itself. Our interest here is primarily with the latter corpus. The central thesis is that much of the knowledge about the planning process itself can be formulated in terms of higher‐level goals and plans called (...) meta‐goals and meta‐plans. These entities can then be used by the same understanding and planning mechanisms that process ordinary goals and plans. However, the meta‐planning knowledge now enables these mechanisms to handle much more complicated situations in a uniform manner.Systems based on meta‐planning would have a number of advantages over existing problem solving and understanding systems. The same knowledge could be shared by both a planner and understander, and both would be able to handle complex situations elegantly. In addition, in planning, the use of meta‐planning has several advantages over more traditional methods involving constraints or critics. Meta‐planning allows the full power of a problem solver to be applied to situations that are generally amenable only to special purpose processing. In addition, meta‐planning facilitates the representation of some situations that are difficult to express otherwise. We have begun to introduce meta‐planning knowledge into two systems: PAM, a story understanding program, and PANDORA, a problem solving and plannin̈g system. (shrink)

A story understander needs a great deal of knowledge about people's goals. This knowledge is needed to infer explanations for the behavior of the characters in a story. Sometimes a character's behavior cannot be explained in terms of a particular goal, but only in relation to a set of recurring goals that a character anticipates having.The concept of goal subsumption is introduced to deal with these situations. Goal subsumption is a way of planning for many goals at the same time. (...) It occurs in three different types of story situations, each of which has its own rules for recognition and understanding. (shrink)

Health care reform is a perennial issue in elections — partly because of the challenges facing health care and especially because health care is an important issue for the swing voters. Making reform happen is harder. There are deep divisions within each of the parties — not apparent during elections. Bipartisan support — and the willingness to accept the best legislation that can be passed as “good enough”— will be key.

We are well into the political season that guarantees the election of a new president. Actually, this season, the election cycle began in November 2006, as soon as the off-year election ended. Not surprisingly, health care and reforming health care are major issues for the election — although somewhat less important than they were before late 2007.I use the phrase “not surprisingly” because there are easily understandable reasons why health care tends to be an election issue whenever we are electing (...) a new president. One obvious reason is that, for several decades, we have been plagued by sizeable numbers of people without health insurance and even more importantly, by unsustainable increases in health care spending and substantial numbers of people experiencing patient safety and clinical appropriateness problems. I regard the unsustainable spending and safety and quality problems as especially important because they affect all of us — not just the 15% of the population that is without health insurance. (shrink)

Finding “common ground” to fix some of the policy problems with the ACA was never expected to be easy. How challenging depends on the election outcome. With split government or even same party control of the Congress and White House but without a supermajority in the Senate, fixing identifiable problems requires remedies that might garner bipartisan cooperation. Some potential strategies that might meet this requirement are described.

v. 1. Sŏngnihak pʻyŏn -- v. 2. Kyŏngse sasang pʻyŏn.

The concept of a proposition is important in several areas of philosophy and central to the philosophy of language. This collection of readings investigates many different philosophical issues concerning the nature of propositions and the ways they have been regarded through the years. Reflecting both the history of the topic and the range of contemporary views, the book includes articles from Bertrand Russell, Gottlob Frege, the Russell-Frege Correspondence, Alonzo Church, David Kaplan, John Perry, Saul Kripke, Hilary Putnam, Mark Richard, Scott (...) Soames, and Nathan Salmon. (shrink)