In developing the metadata standard, reviewers asked that a summary method of providing results also be permitted. While this summary method would not relieve producers of the obligation to provide a thorough report, it would allow users, especially those using a data catalog, to quickly exclude those data sets that obviously would not serve a user's needs. The Horizontal and Vertical Quantitative Positional Accuracy Assessments (and their attribute accuracy counterpart) were provided in response to this request. A producer identifies the test used by name and the value obtained from the test. The derivation of these values should be described in the accuracy reports.
The quality report portion on positional accuracy shall include the degree of compliance to the spatial registration standard (see section 188.8.131.52 [of SDTS]). Quality of control surveys shall be reported by using the procedures established in the geodetic standard. If a separate control survey has been used, it shall be described in the standard form, even if results fall below the recognized classification thresholds.
Descriptions of positional accuracy shall consider the quality of the final product after all transformations. The information on transformations forms a part of the lineage portion of the quality report.
The report of any test of positional accuracy shall include the date of the test. Variations in positional accuracy shall be reported either as additional attributes of each spatial object or through a quality overlay (reliability diagram).
Measures of positional accuracy may be obtained by one of the following optional methods.
Return to: Positional Accuracy