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11.
This paper presents a case study in the production and interpretation of regulatory science, focusing on the conflicting British and American clinical risk assessments of triazolam (Halcion) - the most controversial sleeping pill in the world. The regulation of triazolam is shown to be more permissive in the USA than in the UK. Six principal socio-political factors are put forward to explain this; differential regulatory trust; regulators' socio-technical data selections; medico-scientific disciplinary influences; organizational and professional interests; conflicts of interest of expert advisers; and the growth of the neo-liberal regulatory state. The risk assessments of both the British and American regulatory agencies are shown to be complacent relative to technical standards which the agencies themselves later accepted. It is suggested that, when the interests of pharmaceutical manufacturers and patients diverge, regulatory assessments are crucially affected by whether regulators are predisposed to award the benefit of the scientific doubts to the manufacturers or patients, and by the balance of such predispositions both within and between regulatory institutions of scientific expertise. The triazolam case indicates that the amount of trust placed in the pharmaceutical industry by the British American regulatory systems may hamper detection of flaws in manufacturers' medical data in a timely manner and, as a consequence, compromise patients' interests. Some policy implications for drug regulation are sketched.  相似文献   
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Introduction     
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13.
Generalized Hamming Distance   总被引:4,自引:0,他引:4  
Many problems in information retrieval and related fields depend on a reliable measure of the distance or similarity between objects that, most frequently, are represented as vectors. This paper considers vectors of bits. Such data structures implement entities as diverse as bitmaps that indicate the occurrences of terms and bitstrings indicating the presence of edges in images. For such applications, a popular distance measure is the Hamming distance. The value of the Hamming distance for information retrieval applications is limited by the fact that it counts only exact matches, whereas in information retrieval, corresponding bits that are close by can still be considered to be almost identical. We define a Generalized Hamming distance that extends the Hamming concept to give partial credit for near misses, and suggest a dynamic programming algorithm that permits it to be computed efficiently. We envision many uses for such a measure. In this paper we define and prove some basic properties of the Generalized Hamming distance, and illustrate its use in the area of object recognition. We evaluate our implementation in a series of experiments, using autonomous robots to test the measure's effectiveness in relating similar bitstrings.  相似文献   
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In this paper, I use critical discourse analysis to analyze a student's narrative about the arrest, incarceration, and deportation of her mother to Mexico. The student, Gisela, was a fifth grader in my classroom during the 2008/2009 school year, and I encouraged the students to collect family stories from their relatives. Gisela created this story, and she wrote and illustrated this with the help of her father, student peers, and me. I draw on Gloria Anzaldúa's constructs of nepantla and nepantlera, narrative analysis, and systemic functional linguistics to show how Gisela's construed this story to create a powerful and creative narrative that disrupted autonomous forms of literacy along with the excluding and damaging discourses circulating about immigrants in our community.  相似文献   
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Nature watch     
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Many of the most effective compression methods involve complicated models. Unfortunately, as model complexity increases, so does the cost of storing the model itself. This paper examines a method to reduce the amount of storage needed to represent a Markov model with an extended alphabet, by applying a clustering scheme that brings together similar states. Experiments run on a variety of large natural language texts show that much of the overhead of storing the model can be saved at the cost of a very small loss of compression efficiency.  相似文献   
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Educational Psychology Review -  相似文献   
20.
Despite the impact of genetics on daily life, biology undergraduates understand some key genetics concepts poorly. One concept requiring attention is dominance, which many students understand as a fixed property of an allele or trait and regularly conflate with frequency in a population or selective advantage. We present the Dominance Concept Inventory (DCI), an instrument to gather data on selected alternative conceptions about dominance. During development of the 16-item test, we used expert surveys (n = 12), student interviews (n = 42), and field tests (n = 1763) from introductory and advanced biology undergraduates at public and private, majority- and minority-serving, 2- and 4-yr institutions in the United States. In the final field test across all subject populations (n = 709), item difficulty ranged from 0.08 to 0.84 (0.51 ± 0.049 SEM), while item discrimination ranged from 0.11 to 0.82 (0.50 ± 0.048 SEM). Internal reliability (Cronbach''s alpha) was 0.77, while test–retest reliability values were 0.74 (product moment correlation) and 0.77 (intraclass correlation). The prevalence of alternative conceptions in the field tests shows that introductory and advanced students retain confusion about dominance after instruction. All measures support the DCI as a useful instrument for measuring undergraduate biology student understanding and alternative conceptions about dominance.  相似文献   
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