linketylink · observation

Undiscovering an Island

Hat Tip to arstechnica for this article

This is a classic example of why we need to question where our data comes from. Once you stop to think about it, there are a number of possible explanations as to how this island came to be on charts and maps when it most likely never was. Effective spatial data analysis needs people’s brains to actually check out any anomalies thrown up when combining datasets. Algorithms can alert us to there being something that ‘needs a closer look’ but the actual looking is probably best done by someone who understands geographic information.

oceanSimilarly, any response to a spatial data anomaly must be informed by a number of factors, including things such as:

  • where the data was sourced from
  • who collected it and why
  • what we are using it to do

In some instances a conservative response is the best way to go, in others, we may get away with ignoring the fact that an anomaly was even found. What we shouldn’t do is assume that there is a “correct response” that will then apply for all possible instances – real life just doesn’t work that way.

Unless you happened to be, or know, an oceanic vulcanologist, ‘floating pumice islands‘ are probably not the explanation that comes to mind!

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Have you fleened your ogglefloggle recently?

Simon Sharwood from the website The Register has written about the online mapping problems caused by weak GPS and sloppy check-ins to social media services from smartphones:

“Next time you check in with foursquare or Facebook, please stand right outside the venue, make sure your smartphone has a very good GPS signal and describe the location accurately.

That’s the wish of the spatial data community, which is getting grumpy about user-generated spatial data.

To understand why…”

Click here to read the full article

Read the comments too!
Particularly if you are wondering about this post’s title…