Fitbit - is it an effective random number generator?

stockhausen

stockhausen

stockhausen

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I own neither a "Fitbit" nor an iPhone so I am not affected by this silliness. However, I was asked by a colleague if I had any idea why the distance and steps reported by a Fitbit and an iPhone differ so wildly and whether any of the reported data is anywhere near accurate.

When comparing steps walked, the Fitbit reports an average of 30% more than an iPhone (Range +16% to +31%)

When comparing distance walked, the Fitbit reports an average of 75% more than an iPhone (Range +56% to +87%)

Any explanation?
Any experience?
 
iphone probably uses gps to track distance whilst fitbit uses number of steps*average distance per step

iphone will usually be held in a pocket and fitbit around your wrist, so when you're sitting still but moving your arms around the fitbit accelerometer might think you're walking sometimes.

Just guessing - i've never owned or used either device.
 
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Does your "friend" shake their wrist a lot when wearing the Fitbit? Muscle memory?

You can get Fitbits with GPS though, so it would help to know a bit more about the situation. I've been pretty surprised when carrying two completely different phones (iPhone and Android) at how similar the step count is, and I generally walk around 3 miles on my daily commute.
 
I ran two MS Bands while troubleshooting a sync issue, one on each arm. Over an average day the difference between the two was around 10%, similar if I didn't sync the phone to the Band. I wouldn't trust any GPS data if it is in a pocket/inside a building as a weak signal will cause you to move around even if sitting at a desk (great for "walking" your buddy in Pokemon Go).
 
There is no way to produce a true random number through code/machines such as PC. Think linear pipelines.

I think you need to go down to radioactivity or some kind of atomic levels to get true random interpretations although I am not sure if even then it will be truly random.

Einstein spent the last few decades of his life trying to prove the world was completely deterministic and that a set of laws could determine every physical situation, see, https://en.wikipedia.org/wiki/Hidden_variable_theory.

Well he was proved wrong apparently, see, https://en.wikipedia.org/wiki/Bell's_theorem.

So as poster said above, depends partly on random generator alogorithm used, other factors will come into play also such as operating system, settings and others.
 
Both of them will use their accelerometers and detect a heel-strike signal. The different mounting / carrying points of them will effect how much noise there is on this signal.

The distance thing is likely due to them assuming different stride lengths. Fitbit will ask you for your height and stride, I don't know about the Apple fit stuff.
 
I always get more steps if I wear the Fitbit on my right wrist compared to my left. No idea wtf is going on there.
 
I have both but never use the iphone pedometer as a lot of the time it's not in my pocket. I'd agree with the first post though, in the iPhone uses GPS, whereas my fitbit assumes that every single step i make, is at my natural gate.

It won't be, some will be smaller, the odd few may be larger. I saw an article in the last few days that tested lots of pedometers and fitbit were one that would consistently read above calories burnt. Maybe this carries over to steps and distance covered.
 
Some good answers (and quite a few "predictable" ones).

We are out for a team lunch tomorrow. I own two GPS devices, I will take them both with me. One of the other guys also owns a GPS. We will go for a "wander" around town and see how all five devices compare - on distance only.

I know that my GPS devices differ but not to that extent - they completely lose the plot if I go into a Pub at lunch time . . . or in fact, any time.
 
probably hasn't set up the fitbit, you need to put your actual step length in (use gps to do a several mile walk, then divide steps on the fitbit by distance travelled on gps, not the take one step and try measuring it) dominate/non dominate arm and set sensitivity so you don't get much extra by just waving arms around.

most people do non of that,
 
[FnG]magnolia;30333259 said:
I thought the point of fitbit was to get you to spend more time exercising rather than it having any real claim to accuracy?
Click to expand...
I don't think so, I think that the point of Fitbit is to make money out of gullible people who would otherwise spend money on Love Hearts in the belief that they are actually Ecstasy or LSD.
 
[FnG]magnolia;30333259 said:
I thought the point of fitbit was to get you to spend more time exercising rather than it having any real claim to accuracy?
Click to expand...

It is, but that's the same with most health tech, be it wearable fitbits or phone apps. Both have drawbacks, but they're trying the same thing.

On the plus side I walked 2km while sitting in my seat last time at Wembley (phone app), or maybe 0.5km (fitbit from clapping). Something got me some exercise credit... :D
 
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