how are stats computed (why do they vary so much?)

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    Nathan

    We calculate ascent and descent manually based on filtering your GPS points. Google maps use their own calculations.

    Gaia GPS on your phone and on the website should show fairly consistent statistics for the same tracks, so I'd like to take a closer look.

    Can you send a copy of the track to support@gaiagps.com?

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    mrlamontsmith

    hi nathan, i sent a copy of the track.  curious to see what you find out.  thanks!

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    mrlamontsmith

    hmmmm, i did another hike last saturday and again the stats are really different.

    1) gaia on my phone shows 13.29  miles, 5013 ft and -4945 feet

    2) gaia online (my laptop) shows 14.6 miles, 7933 ft "total ascent"

    3) google earth shows 13.1 miles, +/- 6533 feet.

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    Ashli Baldwin

    Hi,

    I saw you spoke to Nathan recently via email about this, and he mentioned the discrepancy between the website and app are unusual. At first, we thought it was an error with the stats on gaiagps.com, but it turns out it's an error in stats reporting on Android devices.

    So, with that in mind, a few notes:

    1. We're going to address that stats bug in the app in the next Android update we are able to release

    2. Your stats on gaiagps.com are likely more accurate, however, they are still being affected in some way by the error calculating stats on your device.

    3. Comparing Gaia GPS to Google Earth, I think Gaia GPS is more accurate in most cases. We have algorithms to filter out erroneous points and average/smooth them, too. I think some programs just tally up the stats from each point and it will always give a different result than what you see in Gaia. In this case, it's difficult to say whether Gaia or Google is more accurate, due to the calculation bug I mentioned above.

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    sjmj3us

    Hi

         Since the message is 20 days old I assume the bug fix update hasn't been released. However when it is, will it fix existing tracks, or only new recordings?

         I've sent several Android support issues on ascent calculations and Google Earth seems to be far more believable. I would call your attention to my November 19, 2016 hike. Just adding up the major peaks you get far more than the ascent. In the past I've seen hikes where the low to high is greater than the ascent. It looks to me like GE uses DTED at some level. I get this feeling because if I walk on a very level track, see my walk on November 3, 2015, which is completely flat GaiaGps elevation varies but GE does not. So it looks like GE is using apriori surveyed points.

        I also don't understand what calculating manually means. I assume you have some smoothing, but that seems to be removing some real elevation change. Will the fix address the issues above?

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    Ashli Baldwin

    Hi,

    The update I referenced above got released last week.

    The release addresses errors in calculating stats for recorded tracks that got introduced in the previous update. This includes things like negative speed/time calculations and discrepancies between the app and website. 

    I don't know whether or not your previously recorded track statistics will get fixed or not, as the answer to that depends on several factors, and the best thing to do is update and see. 

    If you experience any further track recording issues with this update, please email support directly by hitting 'Submit a Request' at the top of this page. 

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