| Main Title |
Using 'Found' Data to Augment a Probability Sample: Procedure and Case Study. |
| Author |
Overton, J. M. C.;
Young, T. C.;
Overton, W. S.;
|
| CORP Author |
California Univ., Los Angeles. Dept. of Biology. ;Clarkson Univ., Potsdam, NY. Dept. of Civil and Environmental Engineering. ;Oregon State Univ., Corvallis. Dept. of Statistics.;Corvallis Environmental Research Lab., OR. |
| Publisher |
cJul 92 |
| Year Published |
1992 |
| Report Number |
EPA/600/J-94/223; |
| Stock Number |
PB94-169984 |
| Subjects |
Water quality;
Sampling;
Population(Statistics);
Probability theory;
Estimates;
Data bases;
Mathematical models;
Reprints;
|
| Holdings |
| Library |
|
Call Number |
Additional Info |
Location |
Date Modified |
| NTIS |
|
PB94-169984 |
Most EPA libraries have a fiche copy filed under the call number shown. Check with individual libraries about paper copy. |
NTIS |
09/01/1994 |
|
| Collation |
20p |
| Abstract |
While the probability sampling has the advantage of permitting unbiased population estimates, many past and existing monitoring schemes do not employ probability sampling. The authors describe and demonstrate a general procedure for augmenting an existing probability sample with data from nonprobability-based surveys ('found' data). The procedure uses sampling frame attributes to group the probability and found samples into similar subsets. Subsequently, the similarity is assumed to reflect the representativeness of the found sample for the matching subpopulation. Two methods of establishing similarity and producing estimates are described: pseudo-random and calibration. The pseudo-random method is used when the found sample can contribute additional information on variables already measured for the probability sample, thus increasing the effective sample size. The calibration method is used when the found sample contributes information that is unique to the found observations. For either approach, the found sample data yield observations that are treated as a probability sample, and population estimates are made according to a probability estimation protocol. To demonstrate these approaches, the authors applied them to found and probability samples of stream discharge data for the southeastern US. |
| Supplementary Notes |
Pub. in Environmental Monitoring and Assessment, v26 p65-83 1993. See also PB88-170840 and PB94-160595. Prepared in cooperation with Clarkson Univ., Potsdam, NY. Dept. of Civil and Environmental Engineering. and Oregon State Univ., Corvallis. Dept. of Statistics. Sponsored by Corvallis Environmental Research Lab., OR. |
| NTIS Title Notes |
Journal article. |
| Title Annotations |
Reprint: Using 'Found' Data to Augment a Probability Sample: Procedure and Case Study. |
| Category Codes |
68D; 72F |
| NTIS Prices |
PC A03/MF A01 |
| Primary Description |
600/02 |
| Document Type |
NT |
| Control Number |
418226495 |
| Cataloging Source |
NTIS/MT |
| Origin |
NTIS |
| Type |
CAT |
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