Spatial Quality and Anomalies Diagnosis (SQUAD) Tool (ArcGIS and QGIS)

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Abstract:

MEASURE Evaluations Spatial Quality Anomalies Diagnosis (SQUAD) Tool can rapidly identify the presence of certain anomalies, which can then be investigated further to determine if there is a data quality issue.

When working with datasets, ensuring the quality of data is always a challenge. The challenge increases with large datasets that contain hundreds or thousands of geographic coordinates. Validating spatial data can quickly become overwhelming since it is necessary to check the accuracy of both thespatialinformation (the accuracy and precision of the recorded coordinates) and theattributeinformation (data associated with that location, such as a location name, address, or associated administrative unit). Both of these domains must be accurate, and they must be in agreement.

When working with large spatial data sets, manually reviewing each record to validate both location and attribute information can be prohibitively time-consuming. A more effective approach would be to look for anomalies in the data that may indicate data quality issues. MEASURE EvaluationsSpatial Quality Anomalies Diagnosis (SQUAD) Toolcan rapidly identify the presence of any of these anomalies, which can then be investigated further to determine if there is a data quality issue. Narrowing the focus to records most likely to have an error will greatly reduce the time and effort necessary to identify and resolve errors in a database. This tool may not identify every record that has incorrect information, but it will systematically identify records that should be investigated further to resolve anomalies.

The tool produces a list of which records need to be corrected, and it also gives specific feedback on what may be wrong with the data. If these errors are identified early on, the dataset can be corrected and made stronger, more useful, and more trusted.

The SQUAD tool comes in two versions:One requires the use ofArcGIS10.3 or newer with an advanced license.The other requires the use ofQGISand works in version 2.18 or 3.0.(QGIS is a fully open-sourced GIS, which available as a free downloadfromhttp://qgis.org.)

Go to the ArcGIS version

Go to the QGIS version

Shortname: cl-19-011

Author(s): Spencer J, Wilkes B

Year: 2017 (Updated 2018)

Language: English