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(11 Posts)
Occasional Contributor

Automated data checks help organizations efficiently detect errors and ensure that data adheres to business rules and quality standards. As users of spell-check programs know, however, some errors cannot be detected by automated methods. In this course, you will learn visual review techniques to supplement automated data checks. This second layer of quality control is essential to ensure the accuracy of mission-critical GIS data and all the products derived from that data. Learn how to:

  • Identify scenarios when a visual data review is appropriate.
  • Generate a statistically significant random sample of your data for review and analysis.
  • Create a polygon grid to guide a systematic visual review of feature geometry.
  • Indicate missing, misplaced, miscoded, or redundant features.
  • Inspect versioned data and identify differences between versions.

Check it out today!

Data QC with ArcGIS: Visual Review

If you found this course helpful, you may also enjoy the following complementary course. This course teaches automated workflows to ensure data adheres to your organization's quality standards. You will learn about the three phases of the quality control life cycle and techniques to validate data consistently and efficiently.

Data QC: Automating Validation

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Occasional Contributor

The third edition of Building European Spatial Data Infrastructures presents an update on the efforts of the European Union (EU) to create a system for spatial data sharing among the 28 EU member nations. Building a spatial data infrastructure (SDI)—a common framework or language for sharing geographic information—will make providing geographic information and developing geographic information system (GIS)-based applications easier within the EU...  Read more here.

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Occasional Contributor

Geodesy is defined as the science of accurately measuring and understanding the Earth's geometric shape, orientation in space, and gravity field.  Or, as NASA puts it, it is the study of where you are, where you've been, and where you are going.  Simple enough, right?  Geodesy as a science has existed for thousands of years, evolving from equations based on point-to-point data to space-based measurements used to determine coordinate systems for mapping our planet.

If you have studied geography or worked with GIS, you have relied on geodetic standards to provide context for your data.  The following video put out by NASA does a fantastic job of explaining the basics of Geodesy - what it is, where it came from, and how it forms the foundation of our study of the earth.  Check it out and share - this would be a great intro video for students or those in training to learn more about the field.

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Occasional Contributor

There’s something wonderfully appealing about historical maps.  Perhaps it is knowing how much work went into them – the time spent exploring and surveying, the attention required to manually draw and label features – that elevates maps beyond social, political, and scientific necessities.  Maps of the past are works of art, which also contain valuable information about the history of places.

With today’s advanced technology, we no longer have to rely on reprints and museum displays to view maps from the pre-digital age.  The USGS, in partnership with Esri, has released a Historical Topographic Map Explorer that allows you to view over 178,000 maps dating back to the late 19th century.  Search for or pan to your location and dynamically view up to 130 years of cartographic records.

I could get lost (pun intended) in this site for hours.  For example, searching on my hometown of Redlands, California brings up a timeline of maps dating back to 1901.  After downloading a copy of the earliest USGS map of my area for closer inspection, I was amazed to see the suburban sprawl I am accustomed to was nothing but country roads and orange groves so long ago.  On the website, the historical maps are placed right on top of the modern web map, and a slide bar on the left allows you to adjust the transparency for instant comparison.

USGS historical maps - Redlands.png

Not only could this tool be useful for academic and analytical purposes, but on a personal level, it brings the past to life. I love being able to see how the little town my grandmother was born in has grown into the thriving development I know today. Cartography as an art and science has evolved drastically in the last century, and I am delighted to see the hard work and brilliant creations of our predecessors digitized and made available for viewing in such a vibrant, interactive format.

For a more in-depth look at the many features of the USGS Historical Topographic Map Explorer, check out this article on ArcWatch.

Have you used the USGS Topographic Map Explorer?  What did you think?  How has your location changed in the last century?

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Occasional Contributor

There is a geospatial component to every decision that must be made, from the day-to-day management of our personal lives to the bigger national and international issues.  Governments often find themselves stymied, tasked with coordinating massive immediate responses to events without having access to the most pertinent information.  This is changing with the advances in GIS.  National Mapping Organizations are now able to update large quantities of data quickly and disseminate it to first responders and policy makers.  GIS provides information to those that need it when they need it, whether they are at their desks or in the field, leading to more informed decision-making in the public sector.

In the following interview, Esri's Mark Cygan speaks with Kelly Ng of FutureGov on how GIS provides a foundation for evidence-based decision making:

Esri: How can geospatial data support better decision making in government?

Let us know - what is your experience with GIS in government?  Has it made an impact on how decisions are reached and responses coordinated? Where do you think quick access to geospatial information by those in government would make the biggest difference?

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Occasional Contributor

Geospatial advances allow users to create national maps at unprecedented scales, faster than ever before.  Esri's Mark Cygan and Dr. Kumar Navulur with Digital Globe co-authored the following article in the Earth Imaging Journal, discussing the ongoing revolution in national GIS: 

Creating National Maps with GIS and Satellite Imagery : Earth Imaging Journal: Remote Sensing, Satel...

What do you think?  Have you witnessed firsthand the changes in national mapping in recent years, due to advancing technology?

Head over to the Mapping and Charting Space on GeoNet to join the discussion!

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