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  • Its a known issue and there is plenty of test data already to show the over counting when not stepping. Its not going to get any better without a different approach.

  • The threshold is finely balanced. Its purpose is to say, if we dont have activity above this threshold then dont look for steps. Setting too low you overcount, too high and you undercount. Setting above 15 reduces 10K step accuracy down to 95% or less which for me is too low. For a step counter to be consider good it should be 98% - I have that in a paper somewhere. 95% accuracy looks like 9500 steps counted when the fitbit would count 10,000. To me thats too inaccurate.

    Was threshold 15 really the best approach then, and not a slightly higher one?

    The new DC filter means we have to gather more data. What the DC filter does is correctly compensate for positive bias in the signal (ie it would look like the average eas not 0 but say 5). Now that we are compensating for bias then we need to gather more data. My gut feel for it (and supported by test harness runs) is that somewhere between 14 and 15 is the right value.

    BUT it is really hard to know what is going on out there. Not everyone with a B2 reads or posts to this forum and some may just not be interested in steps at all. We really need some sort of polling system in the forum 'is the step counter good enough ? ' 0 for poor, 10 for excellent.

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