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Activity Number:
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83
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Type:
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Contributed
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Date/Time:
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Monday, August 4, 2003 : 8:30 AM to 10:20 AM
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Sponsor:
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Section on Survey Research Methods
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| Abstract - #301629 |
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Title:
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Computer-assisted Probability Sampling in the Field
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Author(s):
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Pushpal Mukhopadhyay*+ and Sarah M. Nusser
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Companies:
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Iowa State University and Iowa State University
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Address:
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116 H University Village, Ames, IA, 50010-8889,
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Keywords:
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computer-assisted data collection ; field survey
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Abstract:
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Probability sampling designs for biological field studies have been largely limited by the difficulty of locating random points in the field. The ability to receive precise GPS signals in many field settings has largely removed this constraint. We have been investigating statistical and computer-based technologies that enable field data collectors to use more sophisticated probability sampling designs. In particular, our research has focused on a scenario in which a field data gatherer can use a mobile computer to download geospatial data for the target region from the internet and use the geospatial data layer as a basis for selecting a probability sample real-time in the field. We will discuss this research through an example with prototype software, which allows stratified random sampling with geographic strata defined as regular rectangles on an arbitrary geographic image covering the target area, or as classes derived from a discrete-valued image such as a land cover map. The software also facilitates adaptive sampling designs for detecting rare events. We discuss extensions of this research that include using covariate data layers to determine selection probabilities.
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