Accuracy Assessment FAQ Metadata

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Frequently-anticipated questions:

• What does this data set describe?
  1. How should this data set be cited?
  2. What geographic area does the data set cover?
  3. What does it look like?
  4. Does the data set describe conditions during a particular time period?
  5. What is the general form of this data set?
  6. How does the data set represent geographic features?
  7. How does the data set describe geographic features?
  8. What biological taxa does this data set concern?
• Who produced the data set?
  1. Who are the originators of the data set?
  2. Who also contributed to the data set?
  3. To whom should users address questions about the data?
• Why was the data set created?
• How was the data set created?
  1. What methods were used to collect the data?
  2. From what previous works were the data drawn?
  3. How were the data generated, processed, and modified?
  4. What similar or related data should the user be aware of?
• How reliable are the data; what problems remain in the data set?
  1. How well have the observations been checked?
  2. How accurate are the geographic locations?
  3. How accurate are the heights or depths?
  4. Where are the gaps in the data? What is missing?
  5. How consistent are the relationships among the data, including topology?
• How can someone get a copy of the data set?
  1. Are there legal restrictions on access or use of the data?
  2. Who distributes the data?
  3. What's the catalog number I need to order this data set?
  4. What legal disclaimers am I supposed to read?
  5. How can I download or order the data?
• Who wrote the metadata?

What does this data set describe?

1. How should this data set be cited?

   U.S. Geological Survey, and Department of the Interior, 199810, Scotts Bluff National Monument Accuracy Assessment: USGS-NPS Vegetation Mapping Program Scotts Bluff National Monument, USGS Core Science Systems, Core Science Analytics and Synthesis, Denver, CO.

   Online Links:

   • <http://biology.usgs.gov/npsveg/ftp/vegmapping/scbl/scblaa.zip>

2. What geographic area does the data set cover?

   West_Bounding_Coordinate: -103.74663

   East_Bounding_Coordinate: -103.68121

   North_Bounding_Coordinate: 41.86887

   South_Bounding_Coordinate: 41.80845

   Description_of_Geographic_Extent: Scotts Bluff National Monument, Nebraska and environs.

3. What does it look like?

   <http://biology.usgs.gov/npsveg/scbl/images/scblaa.pdf> (PDF)

   429 kbyte file showing vegetation associations and location of accuracy assessment points

4. Does the data set describe conditions during a particular time period?

   Calendar_Date: Oct-1998

   Currentness_Reference: Source of data collection

5. What is the general form of this data set?

   Geospatial_Data_Presentation_Form: database and report

6. How does the data set represent geographic features?
   1. How are geographic features stored in the data set?

      This is a Point data set.

   2. What coordinate system is used to represent geographic features?

      Grid_Coordinate_System_Name: Universal Transverse Mercator

      Universal_Transverse_Mercator:

      UTM_Zone_Number: 13

      Transverse_Mercator:

      Scale_Factor_at_Central_Meridian: 0.9996

      Longitude_of_Central_Meridian: -105

      Latitude_of_Projection_Origin: 0

      False_Easting: 500000

      False_Northing: 0

      Planar coordinates are encoded using coordinate pair
      Abscissae (x-coordinates) are specified to the nearest 1
      Ordinates (y-coordinates) are specified to the nearest 1
      Planar coordinates are specified in meters

      The horizontal datum used is North American Datum of 1983.
      The ellipsoid used is Geodetic Reference System 80.
      The semi-major axis of the ellipsoid used is 6378137.
      The flattening of the ellipsoid used is 1/297.257.
      

7. How does the data set describe geographic features?

   Entity_and_Attribute_Overview:

   The National Vegetation Classification Standard is organized hierarchically to support conservation and resource stewardship applications across multiple scales. The upper levels of the hierarchy are based on the physical form or structure of the vegetation (physiognomy) and have been refined from the international standards developed by the United nations Educational, Scientific, and Cultural Organization (UNESCO). The two most detailed levels of the hierarchy are based on the species composition of existing vegetation (floristics) and reflect the phyto-sociological standards that were originally developed by European ecologists. The vegetation classification is continually advanced through the collection and analysis of new field data and will be greatly strengthened during the course of the USGS-NPS mapping efforts. Data file attributes include species, alliance, community element, and land cover.

   0=no data
   1=Juniperus scopularum/Orysopsis micrantha Woodland
   2=Pinus ponderosa/Juniperus scopularum Woodland
   3=Populus deltoides - (Salix amygdaloides)/Salix exigua Fldpln
   4=Salix exigua Shrubland
   5=Andropogon halii --Calamovilfa longifolia Herbaceous Veg.
   6=Cercocarpus montanus/Bouteloua curtipendula Shrubland
   7=Symphoricarpus occidentalis Shrubland
   8=Typha spp. -Equisetum hyemale/Carex spp. Seep Herbaceous
   9=Kochia scoparia/Bromus spp. Early Seral Community
   10=Mixed Grass Prairie (reseeded)
   11=Pascopyrum smithii Herbaceous Vegetation
   12=Stipa comata -Bouteloua gracilis/Carex filfoliaHerb. Veg.
   13=Riverine Sand Flats/Bars
   14=Rock Outcrop/Prairie Mosaic
   15=Siltstone - Clay Butte Sparse Vegetation
   16=Open Bluff/Cliff & Eroding Great Plains Badlands Sparse Veg.
   17=Andropogon gerardii -Calamagrostis canadensis - Helianthus g.
   18=Cliff/Rock Outcrop/Prairie Mosaic
   19=Eroding Great Plains Slopes Sparse Vegetation
   20=Water
   21=Unvegetated landuse / disturbance
   22=Pinus ponderosa/Juniperus scopularum Woodland

   Entity_and_Attribute_Detail_Citation:

   Grossman, D. Et al. 1994. National Park Service/ National Biological Service Vegetation Mapping Project, Standardized National Vegetation Classification System 209 pp.

8. What biological taxa does this data set concern?

   Taxonomy:

   Keywords/Taxon:

   Taxonomic_Keyword_Thesaurus: None

   Taxonomic_Keywords: vegetation classification

   Taxonomic_Keywords: Standardized National Vegetation Classification System

   Taxonomic_Keywords: alliance

   Taxonomic_Keywords: community association

   Taxonomic_System:

   Classification_System/Authority:

   Classification_System_Citation:

   Citation_Information:

   Originator: U.S. Government; Federal Geographic Data Committee

   Publication_Date: 19971022

   Title: National Vegetation Classification Standard (NVCS)

   Geospatial_Data_Presentation_Form: document

   Publication_Information:

   Publication_Place: Washington D.C.

   Publisher: Federal Geographic Data Committee

   Online_Linkage:

   <http://www.fgdc.gov/standards/projects/FGDC-standards-projects/vegetation/index_html>

   Taxonomic_Procedures:

   Vegetation associations were identified; no specimens nor vouchers were collected as a part of this process.

   Taxonomic_Completeness:

   Conforms with FGDC standardized vegetation classification system.

   Taxonomic_Classification:

   Taxon_Rank_Name: Kingdom

   Taxon_Rank_Value: Plantae

   Applicable_Common_Name: plants

Who produced the data set?

1. Who are the originators of the data set? (may include formal authors, digital compilers, and editors)
   • U.S. Geological Survey
   • Department of the Interior

2. Who also contributed to the data set?

3. To whom should users address questions about the data?
   USGS/CSS/Core Science Analytics and Synthesis
   c/o USGS-NPS Vegetation Mapping Program Coordinator
   Denver Federal Center, Building 810, Room 8000, MS 302
   Denver, Colorado 80225
   

   (303) 202-4220 (voice)
   303-202-4219 (FAX)
   gs-b-npsveg@usgs.gov
   

Why was the data set created?

To verify the accuracy of the mapped vegetation communities at Scotts Bluff National Monument

How was the data set created?

1. What methods were used to collect the data?

   Method 0 of 2

   Type: Field

   Data points were located by use of a PLGR GPS receiver. Vegetation communities were identified on the basis of a dichotomous field key and plant Species: present

   Method 0 of 2

   Type: Lab

   Accuracy assessment points were compiled into an ARCINFO point coverage and intersected with the vegetation community coverage. The resulting INFO file was exported into a text file, imported into a spreadsheet, and the attributes from the accuracy assessment and the spatial data were compared. If the attributes did not compare, an analysis of the mismatch was made and either the AA attribute or the map attribute was changed based on identification of the community on the aerial photo.

   From what previous works were the data drawn?

   Accuracy Assessment Procedures Document (source 1 of 2)

   U.S. National Biological Survey, U.S. National Park Service, and Department of the Interior, 199411, Accuracy Assessment Procedures, NBS/NPS Vegetation Mapping Program: USGS, Core Science Systems, Core Science Analytics and Synthesis, Denver, CO.

   Other_Citation_Details:

   Prepared by: Environmental Systems Research Institute; Redlands, CA and National Center for Geographic Information and Analysis, University of California, Santa Barbara, CA anbd The Nature Conservancy, Arlington, VA under contract from U.S. Department of the Interior National Biological Survey and National Park Service.

   Type_of_Source_Media: electronic document

   Source_Contribution:

   This document established the procedures and protocols for the accuracy assessment at Scotts Bluff National Monument.

   Spatial data of vegetation communities for Scotts Bluff National Monument. (source 2 of 2)

   U.S. Geological Survey, and Department of the Interior, 199809, Scotts Bluff National Monument Spatial Vegetation Data: Cover type / Association level of the National Vegetation Classification System: USGS-NPS Vegetation Mapping Program Scotts Bluff National Monument, USGS, Core Science Systems, Core Science Analytics and Synthesis, Denver, CO.

   Other_Citation_Details:

   Created in large part by Environmental Systems Research Institute, Inc. Redlands, CA under contract rom USGS/CSS/CSAS.

   Type_of_Source_Media: Disc

   Source_Contribution:

   The vegetation spatial data were tested for accuracy with the AA data.

   How were the data generated, processed, and modified?

   Date: Oct-1998 (process 1 of 1)

   The accuracy assessment field work was performed in August, 1997 to verify the accuracy of the vegetation communities spatial data developed by the USGS-NPS Vegetation Mapping Program for Scotts Bluff National Monument. The data points were randomly distributed stratified according to vegetation association over the project area according to protocols developed by the Program. Points were located by GPS navigation and the community information was collected at the point, without knowledge of the attributes of the vegetation spatial data.

   Data sources used in this process:

   • Spatial data of vegetation communities for Scotts Bluff National Monument.
   • Accuracy Assessment Procedure Document

   What similar or related data should the user be aware of?

How reliable are the data; what problems remain in the data set?

1. How well have the observations been checked?

   The attributes for the accuracy assessment were recorded in the field in August, 1997. Vegetation associations were identified based on the field key and plant identification. If additional communities were found within a 50 meter radius of the plot center, they were recorded as well. During the analysis, it was concluded that some attributes were in error and changed to match the mapped attributes. This was done by examination of the aerial photographs under stereoscopic view. The attributes were in error due to 1) spatial error in the GPS derived coordinates (4-8 meters), 2) change of vegetation community due to temporal changes, or differences between observation team identifications.

2. How accurate are the geographic locations?

   The points were located using a military-style GPS receiver (PLGR), which has a published accuracy of 4-8 meters.

3. How accurate are the heights or depths?

   Not applicable

4. Where are the gaps in the data? What is missing?

   All points were collected and analyzed. Several points fell outside the mapping area, so were discarded.

5. How consistent are the relationships among the observations, including topology?

   All attributes are codes that correspond to vegetation communities and have been checked for typographical and logical errors.

How can someone get a copy of the data set?

Are there legal restrictions on access or use of the data?

Access_Constraints: None

Use_Constraints:

Any person using the information presented here should fully understand the data collection and compilation procedures, as described in these metadata, before beginning analysis. The burden for determining fitness for use lies entirely with the user. For purposes of publication or dissemination, citation or credit should be given to the U.S. Geological Survey and the National Park Service.

1. Who distributes the data set? (Distributor 1 of 1)
   USGS/CSS/Core Science Analytics and Synthesis
   c/o USGS-NPS Vegetation Mapping Program Coordinator
   Denver Federal Center, Building 810, Room 8000, MS 302
   Denver, Colorado 80225
   

   (303) 202-4220 (voice)
   303-202-4219 (FAX)
   gs-b-npsveg@usgs.gov
   

2. What's the catalog number I need to order this data set?

3. What legal disclaimers am I supposed to read?

   The U.S. Geological Survey and the National Park Service shall not be held liable for improper or incorrect use of the data described and/or contained herein. These data and related graphics (if available) are not legal documents and are not intended to be used as such.

   The information contained in these data is dynamic and may change over time. The data are not better than the original sources from which they were derived. It is the responsibility of the data user to use the data appropriately and consistent within the limitations of geospatial data in general and these data in particular. Any related graphics (if available) are intended to aid the data user in acquiring relevant data; it is not approriate to use the related graphics as data.

   The U.S. Geological Survey and the National Park Service gives no warranty, expressed or implied, as to the accuracy, reliability, or completeness of these data. It is strongly recommended that these data are directly acquired from an U.S. Geological Survey and National Park Service servers and not indirectly through other sources which may have changed the data in some way. Although these data have been processed successfully on a computer system at the U.S. Geological Survey, no warranty expressed or implied is made regarding the utility of the data on another system or for general or scientific purposes, nor shall the act of distribution constitute any such warranty. This disclaimer applies both to individual use of the data and aggregate use with other data. It is also strongly recommended that careful attention be paid to the contents of the metadata file associated with these data. Mention of trade names or commercial products in this metadata report does not constitute endorsement or recommendation for use by the U. S. Department of the Interior, U. S. Geological Survey and National Park Service.

4. How can I download or order the data?
   • Availability in digital form:

     Data format:	HTML
     Network links:	<http://biology.usgs.gov/npsveg/scbl/index.html>

   • Cost to order the data: None

Who wrote the metadata?

Dates:

Last modified: 22-Oct-2001
Last Reviewed: 15-Jun-2010

Metadata author:

USGS/CSS/Core Science Analytics and Synthesis
c/o USGS-NPS Vegetation Mapping Program Coordinator
Denver Federal Center, Building 810, Room 8000, MS 302
Denver, Colorado 80225

(303) 202-4220 (voice)
303-202-4219 (FAX)
gs-b-npsveg@usgs.gov

Metadata standard:

FGDC Biological Data Profile of the Content Standard for Digital Geospatial Metadata (FGDC-STD-001.1-1999)

Metadata extensions used:

• <http://www.nbii.gov/portal/server.pt/community/fgdc_metadata/255>