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11.
Roger M. A. Allen 《Muslim world (Hartford, Conn.)》1972,62(2):115-125
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Road safety research is a data-rich field with large social impacts. Like in medical research, the ambition is to build knowledge around risk factors that can save lives. Unlike medical research, road safety research generates empirical findings from messy observational datasets. Records of road crashes contain numerous intersecting categorical variables, dominating patterns that are complicated by confounding and, when conditioning on data to make inferences net of this, observed effects that are subject to uncertainty due to diminishing sample sizes. We demonstrate how visual data analysis approaches can inject rigor into exploratory analysis of such datasets. A framework is presented whereby graphics are used to expose, model and evaluate spatial patterns in observational data, as well as protect against false discovery. Evidence for the framework is presented through an applied data analysis of national crash patterns recorded in STATS19, the main source of road crash information in Great Britain. Our framework moves beyond typical depictions of exploratory data analysis and transfers to complex data analysis decision spaces characteristic of modern geographical analysis. 相似文献
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T he technological prowess of the U nited S tates was symbolized by what became known as the space shuttle, which the National Aeronautics and Space Administration (NASA) began to work on in the late 1960s. With the shuttle program NASA planned to facilitate its aggressive space-exploration effort by providing low-cost, reusable transportation to and from Earth's orbit. NASA officials compared the space program's traditional use of expendable launch vehicles to throwing away a railroad locomotive after every train trip, whereas a reusable shuttle would offer cost-effective, routine access to space. Approval of the shuttle initiative required complex political maneuvering by NASA and its supporters between 1969 and 1972. The twists and turns in the approval process actually shaped the final direction that the shuttle program took, demonstrating the pitfalls of decision making by compromise and the challenges of managing large-scale technology programs within the federal government.1 相似文献
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Roger Allen Catherine Asher Michael Bates Daniel Bradburd Robert L. Canfield Howard Crane 《Iranian studies》1995,28(3-4):231-281
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