84,772 research outputs found
An immune network approach to learning qualitative models of biological pathways
ACKNOWLEDGMENT GMC is supported by the CRISP project (Combinatorial Responses In Stress Pathways) funded by the BBSRC (BB/F00513X/1) under the Systems Approaches to Biological Research (SABR) Initiative. WP and GMC are also supported by the partnership fund from dot.rural, RCUK Digital Economy research.Postprin
Diagnosis by integrating model-based reasoning with knowledge-based reasoning
Our research investigates how observations can be categorized by integrating a qualitative physical model with experiential knowledge. Our domain is diagnosis of pathologic gait in humans, in which the observations are the gait motions, muscle activity during gait, and physical exam data, and the diagnostic hypotheses are the potential muscle weaknesses, muscle mistimings, and joint restrictions. Patients with underlying neurological disorders typically have several malfunctions. Among the problems that need to be faced are: the ambiguity of the observations, the ambiguity of the qualitative physical model, correspondence of the observations and hypotheses to the qualitative physical model, the inherent uncertainty of experiential knowledge, and the combinatorics involved in forming composite hypotheses. Our system divides the work so that the knowledge-based reasoning suggests which hypotheses appear more likely than others, the qualitative physical model is used to determine which hypotheses explain which observations, and another process combines these functionalities to construct a composite hypothesis based on explanatory power and plausibility. We speculate that the reasoning architecture of our system is generally applicable to complex domains in which a less-than-perfect physical model and less-than-perfect experiential knowledge need to be combined to perform diagnosis
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Where Are My Intelligent Assistant's Mistakes? A Systematic Testing Approach
Intelligent assistants are handling increasingly critical tasks, but until now, end users have had no way to systematically assess where their assistants make mistakes. For some intelligent assistants, this is a serious problem: if the assistant is doing work that is important, such as assisting with qualitative research or monitoring an elderly parentâs safety, the user may pay a high cost for unnoticed mistakes. This paper addresses the problem with WYSIWYT/ML (What You See Is What You Test for Machine Learning), a human/computer partnership that enables end users to systematically test intelligent assistants. Our empirical evaluation shows that WYSIWYT/ML helped end users find assistantsâ mistakes significantly more effectively than ad hoc testing. Not only did it allow users to assess an assistantâs work on an average of 117 predictions in only 10 minutes, it also scaled to a much larger data set, assessing an assistantâs work on 623 out of 1,448 predictions using only the usersâ original 10 minutesâ testing effort
Validation and analysis of the coupled multiple response Colorado upper-division electrostatics (CUE) diagnostic
Standardized conceptual assessment represents a widely-used tool for
educational researchers interested in student learning within the standard
undergraduate physics curriculum. For example, these assessments are often used
to measure student learning across educational contexts and instructional
strategies. However, to support the large-scale implementation often required
for cross-institutional testing, it is necessary for these instruments to have
question formats that facilitate easy grading. Previously, we created a
multiple-response version of an existing, validated, upper-division
electrostatics diagnostic with the goal of increasing the instrument's
potential for large-scale implementation. Here, we report on the validity and
reliability of this new version as an independent instrument. These findings
establish the validity of the multiple-response version as measured by multiple
test statistics including item difficulty, item discrimination, and internal
consistency. Moreover, we demonstrate that the majority of student responses to
the new version are internally consistent even when they are incorrect, and
provide an example of how the new format can be used to gain insight into
student difficulties with specific content in electrostatics.Comment: 8 pages, 6 figures, submitted to Phys. Rev. ST-PE
Comparative analysis of knowledge representation and reasoning requirements across a range of life sciences textbooks.
BackgroundUsing knowledge representation for biomedical projects is now commonplace. In previous work, we represented the knowledge found in a college-level biology textbook in a fashion useful for answering questions. We showed that embedding the knowledge representation and question-answering abilities in an electronic textbook helped to engage student interest and improve learning. A natural question that arises from this success, and this paper's primary focus, is whether a similar approach is applicable across a range of life science textbooks. To answer that question, we considered four different textbooks, ranging from a below-introductory college biology text to an advanced, graduate-level neuroscience textbook. For these textbooks, we investigated the following questions: (1) To what extent is knowledge shared between the different textbooks? (2) To what extent can the same upper ontology be used to represent the knowledge found in different textbooks? (3) To what extent can the questions of interest for a range of textbooks be answered by using the same reasoning mechanisms?ResultsOur existing modeling and reasoning methods apply especially well both to a textbook that is comparable in level to the text studied in our previous work (i.e., an introductory-level text) and to a textbook at a lower level, suggesting potential for a high degree of portability. Even for the overlapping knowledge found across the textbooks, the level of detail covered in each textbook was different, which requires that the representations must be customized for each textbook. We also found that for advanced textbooks, representing models and scientific reasoning processes was particularly important.ConclusionsWith some additional work, our representation methodology would be applicable to a range of textbooks. The requirements for knowledge representation are common across textbooks, suggesting that a shared semantic infrastructure for the life sciences is feasible. Because our representation overlaps heavily with those already being used for biomedical ontologies, this work suggests a natural pathway to include such representations as part of the life sciences curriculum at different grade levels
The Narrow Conception of Computational Psychology
One particularly successful approach to modeling within cognitive science is computational psychology. Computational psychology explores psychological processes by building and testing computational models with human data. In this paper, it is argued that a specific approach to understanding computation, what is called the ânarrow conceptionâ, has problematically limited the kinds of models, theories, and explanations that are offered within computational psychology. After raising two problems for the narrow conception, an alternative, âwide approachâ to computational psychology is proposed
Making the Public Case for Child Abuse and Neglect Prevention: A FrameWorks Message Memo
The goal of this work is to evaluate the existing body of research available to Prevent Child Abuse America against the findings that emerge from new research, and to identify promising ways to reframe these issues in ways that engage people in prevention, motivate them to prioritize proven policies and programs, and overcome existing mental roadblocks. To that end, this Memo attempts to describe the translation process necessary to engage the public in solutions by identifying specific practices that research suggests would advance public understanding as well as those that are likely to impede it.This research analysis is part of New FrameWorks Research on Child Abuse and Neglect Prevention. Please visit our website for more information
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