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NRI Data AvailabilityFor the 2003 Annual NRI (Land Use, Soil Erosion, Wetlands) and previous Annual NRIs, the only data available is summary data published solely on this Web site (no CD-ROM of 'raw' sample point data will be published). If you desire additional 1997 NRI data not presented on this
Web site, you may consult our NRCS State Web Sites and
NRI Coordinators
or order a CD-ROM
of sample point data. Order CD-ROM of 1997 NRI "Raw" Sample Point Data: NRI data for four points in time (1982, 1987, 1992, and 1997) are completely comparable and consistent from year to year so that the data reflect true trends and temporal analyses can be made. When making comparisons with 1982, 1987, and/or 1992 data, the new (1997) NRI database must be used. Originally released 1982, 1987, and 1992 data may not be consistent with the new database. The historical 1982, 1987, and 1992 data were updated to reflect 1997 technical criteria and protocols as part of the 1997 NRI inventory process. The 1997 NRI database should be considered self-contained in that respect. The 1992 dataset is no longer being supported. NRI data were collected at more than 800,000 sample sites nationwide. This is a very large sample, which means that the data can be legitimately used to analyze issues at many geographic levels -- national, regional, State, and sub-State (multi-county). The NRI was not designed to provide statistical estimates for counties or 8-digit hydrologic units; however, examining the data at various geographic levels, including county or 8-digit hydrologic unit, is a legitimate analytical technique for gaining additional insight into the database. Anyone who intends to work with NRI data, especially at the county or 8-digit hydrologic unit scales, should read carefully the technical guidance as to the suitability and limitations of the data and the error-estimation procedures. The CD includes data files of the natural resource data for each sample point, along with the associated georeferences of FIPS code, Hydrologic Unit Code, and Major Land Resource Area Code. The data are presented in comma delimited ASCII format and the user will need to import the data into software applications of their choosing in order to manipulate the data and generate estimates and statistical errors. "A Guide for Users of 1997 NRI Data Files" and reference information is provided.
This document is also available in Adobe Acrobat format.
In order to properly use the CD data, the user must:
* Most common statistical packages will not provide appropriate estimates for the NRI stratified cluster sampling design. However, there are several commercial software packages available to the data analyst that may be used. These include: SAS ® (Release 8.2), SUDAAN ®, and WesVar ®. Additionally, DOS software packages, PC CARP and SUPERCARP, can be obtained from: Statistical Laboratory, Iowa State University, 219 Snedecor Hall, Ames, Iowa 50011; telephone (515) 294-9773. ** There are some limited MS® ACCESS database and SAS® tools provided as a courtesy to users who already own this software, but the software itself is not provided. Use of product names (or trade names) does not imply endorsement of
products (or software systems) by the USDA Natural Resources
Conservation Service. Please be aware that this CD does NOT contain:
Order 1997 NRI DataData for the 48 conterminous United States, Hawaii, Puerto Rico, and the U.S. Virgin Islands are contained on a single CD. Order the CD online . The processing fee for each CD is $50.00. |
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