GPS accuracy vs Precision, what the gps makers don't tell us.

[Cane Pole]

I do not doubt that any of the Waas GPS units are accurate. How accurate really depends on the manufs measuring stick. The manuf are not consistent with these measurements, They kinda make up their own rules, bout like sonar transmit power. There is no consistency amongst the manuf. This maneuver is just to keep us confused so we keep on buying. In other words, a marketing tool.

What I keep asking (and keep getting the run around) is how precise is the device? What is the consistency of precision? After all, there are major differences between accuracy and precision.

In other words if I pass by a marker at a given distance from my boat, will that marker be at the same lat/long if I repeat the pass on the same track?
Several passes at 1mph? At 2 mph? At 3 mph?

You all need to try this out and see for yourself. Locate a river/lake marker and drive by it at different speeds following the same track. Don't mark it. Something to do when the fish ain't co-opin'. Watch your gps position indicator an/or turn on your "ring". Try it and log your results. Pencil and paper make good log devices.

This is good info to know about your own gps.

Let me know your results.

Thanks

Tom