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Re: [RC] GPS accuracy - Sisu West Ranch"...This gives a lower bound on velocity...."I was not considering the speed (the readout on a GPS in MPH or kph is supposed to be speed, not velocity) problem, just the distance problem. I had assumed, wrongly I guess, that the speed was calculated from some number of position fixes and the time of each fix. Like everything else, quality is conformance to customer expectations. If you expect odometer (to distinguish from straight line distance between two waypoints) readings to be accurate to 1% (.5 miles in 50 miles) you are likely to find that you do not have a quality GPS. If on the other hand you expect the odometer to tell you that you rode around 15 miles on your training ride, you will think you have a quality GPS. I assumed that a GPS calculates distance by calculating the straight line distance between two observations. It is good to know that, for the reasons you posted, odometer readings will not get much better than they are now. Ed Ed & Wendy Hauser 2994 Mittower Road Victor, MT 59875 (406) 642-9640 ranch(at)sisuwest(dot)us =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-= Ridecamp is a service of Endurance Net, http://www.endurance.net. Information, Policy, Disclaimer: http://www.endurance.net/Ridecamp Subscribe/Unsubscribe http://www.endurance.net/ridecamp/logon.asp Ride Long and Ride Safe!! =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
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