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Picture of Tom McBrayer
posted
A preliminary ride for a proposed course for the local Race for the Cure is under fire. It's way too long according to a volunteer and his Google Earth map. By about 45 m on his first look-see or 30 m on his 2nd try. The usual arguments aren't working. Has anyone else encountered this version of "my GPS said the course was long". It is my understanding the The Komen Foundation requires a certified course-by USATF, not Google.
 
Posts: 106 | Registered: 14 March 2006Reply With QuoteReport This Post
Picture of Pete Riegel
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I use Google Earth for estimating every measurement, when I can. It's generally accurate enough so that I don't waste time and energy riding my bike all over to hunt other ways to go.

In my experience 30 or 40 meters difference from the final measurement, in a 5k, is fairly normal for my use of Google Earth.

Good luck convincing the Google Earth true believer.


Pete Riegel
 
Posts: 1745 | Location: Columbus, Ohio, USA | Registered: 23 October 2004Reply With QuoteReport This Post
Picture of Mark Neal
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Tom,

Ask the guy to save the kml file and mail it to you. He'll probably tell you that you can't save a measurement path in Google Earth, and he'll be right. I just wanted to take this opportunity to whine about the fact that Google STILL has not fixed this deficiency in GE, which is unbelievable.

Anyway, ask him to draw a regular path over his measurement path and save the result and send it to you. Read it into GE and you'll find that one of the following is true (along with a percent likelihood of each):

25% For a fair number of the turns the path he followed is closer to the LPR than the SPR.

25% A fair number of the turns are not visible due to tree or building cover, so it's impossible to tell if the SPR was followed.

25% For some of the turns it is impossible to determine the boundary between road and sidewalk, so it's impossible to tell if the SPR was followed.

25% He started or finished at the wrong spot, or it's impossible to tell exactly where the start and finish should be because they are located relative to something not visible on the map.

99.9% Some combination of the above.

0.1% Your measurement was wrong.

That last percentage might be a little high.
 
Posts: 933 | Location: Rochester, MI | Registered: 13 April 2006Reply With QuoteReport This Post
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