ArcGIS Data Reviewer: Assessing Positional Accuracy Roslyn Dunn

What is ArcGIS Data Reviewer? Data Quality Management for ArcGIS Provides Rule-based validation Interactive tools Track errors For individuals and enterprise Saves time/money Less rework For multiple domains Configurable Extendable Enterprise Workflow Validate Review Summarize ArcGIS Data Reviewer: Assessing Positional Accuracy

What is ArcGIS Data Reviewer? Data quality management in the ArcGIS platform Desktop Web Device Data Reviewer for Desktop ArcMap ArcGIS Pro Data Reviewer for Server Standard or higher Data Reviewer API JavaScript FLEX Web AppBuilder for ArcGIS Web GIS ArcGIS Online Portal Server Online Content and Services ArcGIS Data Reviewer: Assessing Positional Accuracy

ArcGIS Data Reviewer: Assessing Positional Accuracy Forms of Geospatial Data Accuracy Spatial (position, geometry, topology) Attributional (correctness of attributes) Spectral (band depth) Temporal (appropriate date) Radiometric (capture piece of electromagnetic spectrum) ArcGIS Data Reviewer: Assessing Positional Accuracy

ArcGIS Data Reviewer: Assessing Positional Accuracy Concepts Data needs to be in the “right” place for intended purpose Usually scale-dependent to some degree All else being equal, less accurate is less valuable Data products usually need to conform to a specification ASPRS Positional Accuracy Standards November 2014 Orthoimagery Digital Planimetric Data Digital Elevation Data DMA - Error Theory as Applied to Mapping, Charting, and Geodesy ArcGIS Data Reviewer: Assessing Positional Accuracy

ArcGIS Data Reviewer: Assessing Positional Accuracy Definition of Terms Accuracy The closeness of the best estimated value obtained by the measurements to the “true” value of the quantity measured How well does the measured quantity compare to the “true” value? Positional Accuracy The Quantifiable value that represents the positional difference between two geospatial layers or between a geospatial layer and reality Circular Error (CE) is an error measurement for both X & Y Linear Error (LE) is generally an error measurement for Z (elevation) RMSE is a statistical measurement of the variance between the residual values ArcGIS Data Reviewer: Assessing Positional Accuracy

ArcGIS Data Reviewer: Assessing Positional Accuracy Definition of Terms Circular Error – a two-dimensional error measure (X, Y) CE 90, 95, 99 The radial error which n% of all errors in a circular distribution will not exceed Circular error at n% confidence level e.g. If CE 90 = 2.0 Meters then we are 90% confident that the measurement lies somewhere within a circle with a radius of 2.0 Meters i.e. we’re 90% sure the error won’t be more than 2.0 Meters ArcGIS Data Reviewer: Assessing Positional Accuracy

ArcGIS Data Reviewer: Assessing Positional Accuracy Definition of Terms Linear Error – a one-dimensional error measure (z) A measure of the vertical accuracy of the terrain (e.g. DEM or TIN) The difference between the true or known value and the measured or derived value LE 90, 95, 99 Linear error at n% confidence level e.g. If LE 95 = 10 Meters then we are 95% confident that the “true” elevation measurement is within 10 Meters ArcGIS Data Reviewer: Assessing Positional Accuracy

ArcGIS Data Reviewer: Assessing Positional Accuracy Positional Accuracy Assessment Tool (PAAT) PAAT Tool - Part of GIS Data Reviewer Created with requirements gathered from NGA Determine accuracy of Imagery Rasters Vectors ArcGIS Data Reviewer: Assessing Positional Accuracy

ArcGIS Data Reviewer: Assessing Positional Accuracy Positional Accuracy Assessment Tool (PAAT) Reporting NGA standard or USGS standard CE 90, 95, 99 LE 90, 95, 99 (for DEMs or TINs) RMSE Absolute or relative ArcGIS Data Reviewer: Assessing Positional Accuracy

ArcGIS Data Reviewer: Assessing Positional Accuracy Positional Accuracy Assessment Tool (PAAT) Outputs Text report Optional outputs: Accuracy attribute populated (if assessing vectors) XML Metadata ISO PMAA (NGA) Shapefile of point reading locations ArcGIS Data Reviewer: Assessing Positional Accuracy

Positional Accuracy Assessment Tool (PAAT) DEMO ArcGIS Data Reviewer: Assessing Positional Accuracy

ArcGIS Data Reviewer: Assessing Positional Accuracy Positional Accuracy Assessment Tool (PAAT) Statistical Sampling Time is money Sampling saves time Statistical sampling tool answers the question: “Given a population size, what sample size do I need to be X percent confident that the sample size is statistically significant, within Y percent margin of error?” ArcGIS Data Reviewer: Assessing Positional Accuracy

Want to learn more? Product information www.esri.com/datareviewer ArcGIS Data Reviewer: Assessing Positional Accuracy

Want to learn more? Documentation Training (training.esri.com) Desktop Server Training (training.esri.com) Assessing Data Quality using ArcGIS Data Reviewer (Seminar) Evaluating Positional Accuracy Using ArcGIS Data Reviewer for Desktop (Seminar) Data QC with ArcGIS: Automating Validation (Web Course) Data QC with ArcGIS: Visual Review (Web Course) Quality Control Using ArcGIS Data Reviewer for Desktop (Instructor-Led) Free New ArcGIS Data Reviewer: Assessing Positional Accuracy

Want to learn more this week? Day and Description Type Time Location Tuesday June 28 ArcGIS Data Reviewer: An Introduction Technical Workshop 8:30 – 9:45am Room 15B ArcGIS Data Reviewer: Assessing Positional Accuracy Demo Theater 10:30 – 11:15am Demo Theater 4 Geodata ArcGIS Data Reviewer: Integrating ArcGIS Data Reviewer and ArcGIS Workflow Manager to Automate Data Quality Control Workflows 11:30 – 12:15pm ArcGIS Data Reviewer: Leveraging Geoprocessing for Data Validation 12:30 – 1:15pm ArcGIS Data Reviewer: Quality Assessment for Elevation Raster Datasets 2:30 – 3:15pm Wednesday June 29 3:15 – 4:30pm Sapphire Ballroom A/B Thursday June 30 ArcGIS Data Reviewer: Advanced Data Validation Concepts Room 32 A/B ArcGIS Data Reviewer: Implementing Data Quality Reporting in Web Clients Demo Theater 6 Server ArcGIS Data Reviewer: Integrating Data Validation Capabilities into Web Applications New ArcGIS Data Reviewer: Assessing Positional Accuracy

Thank you… Please fill out the session survey using the Esri Events mobile app Select “ArcGIS Data Reviewer: Assessing Positional Accuracy” session Use the Search Feature to quickly find this title Scroll-down to the “Feedback” section Answer a few short questions, enter any comments and select “Submit”! ArcGIS Data Reviewer: Assessing Positional Accuracy

ArcGIS Data Reviewer: Assessing Positional Accuracy