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GPS glitched across the US by as much as 33 feet

sciencealert.com

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Re: GPS glitched across the US by as much as 33 feet

#111

Post by leptons »

altmanaltman wrote: post #103
leptons wrote: post #102

Earlier quoted context omitted.

>This You're cherry-picking a single word to start a pointless internet argument? Calm down. Nobody claimed this exact event lead to problems for anyone. This is what OP actually said: >>This is exactly the sort of thing Yes, this absolutely is the sort of thing . No, 33 feet isn't "the thing" but GPS glitching is the sort of thing at a different increment.

Okay but the claim is people are being re-arrested because of this "sort of thing". But I read the linked article, and it doesn't mention anyone getting re-arrested. There is only one situation described where the person is arrested and then let go after the cops got proof the alert was faulty. So yes, it absolutely sucks that this technology is so inconvenient and bad but at the same time, the author and GP claims a…

>Also telling people to "calm down" over text when they are not even talking to you is very passive aggresive for no reason.

Your "This" quote was the least genuine comment I've seen on HN in a very long time. You took a comment and removed all context to complain about how it's wrong, when it wasn't wrong at all. There should be no doubt that GPS glitches can cause people with ankle monitors a lot of needless trouble, and "the system" likely won't believe it, and simply won't care.

If you had an ankle monitor, and someone wanted to fuck with you, it would be trivially easy to block or spoof GPS signals to put you back in jail. All it takes is an SDR and some software you can find on github. Think about that before you quip "This" again.

This time the glitch was 33 feet, who's to say next time it couldn't be 3300 feet?

Re: GPS glitched across the US by as much as 33 feet

#112

Post by GJim »

globular-toast wrote: post #109
corndoge wrote: post #106

Earlier quoted context omitted.

> We used it somewhat famously during the 9/11 attacks. I have not been able to locate any source that backs up this claim.

Indeed, the link in the parent even says it hasn't been used since May 2000. So, yeah, it certainly wasn't used "famously". Perhaps the commenter is thinking of the fact it was used globally prior to May 1, 2000. From a civilian point of view, GPS appeared to be invented around this time but it had actually been available for a couple of decades already, just in a degraded form that wasn't very useful.

> just in a degraded form that wasn't very useful

Differential GPS was already in widespread use in many counties by 2000, which made "selective ability" pointless at it provided automatic corrections to the 'degraded' GPS signal.

https://en.wikipedia.org/wiki/Differential_GNSS

Re: GPS glitched across the US by as much as 33 feet

#113

Post by hypfer »

iamshs wrote: post #48
dataflow wrote: post #32

Earlier quoted context omitted.

> This As in, GPS being off by 33 feet? > leads to people getting reincarcerated I'm reading your article and it seems to be about police coming to check and realizing that the reporting of being miles away was in error, not people getting reincarcerted because of GPS incorrectly reporting they moved ~30 feet too far? One of these is much more insane than the other.

The story is about GPS errors which end up making life hell for people under monitoring since they end up generating a Police response. If 80% alerts were false, then an error like this can result in a surge of these alerts. It is an important story to tell.

[flagged]

Re: GPS glitched across the US by as much as 33 feet

#114

Post by the8472 »

Waterluvian wrote: post #34
sen wrote: post #31

Earlier quoted context omitted.

That’s how all “estimated damages” work. It’s all just made up by some random person who guesstimated a number then multiplied it by the maximum possible people effected, realistic or not.

There’s probably a reasonable methodology but it has a lot of multiplications and some base parameters that make the whole thing wildly sensitive.

It's not reasonable because the error bars of each estimate compound and they may not even be normally distributed in the first place. You should rather convolve probability distributions - assuming factors are independent - and if the IQR covers a huge range, perhaps orders of magnitude even, you should state that.

Re: GPS glitched across the US by as much as 33 feet

#115

Post by hypfer »

chaps wrote: post #52
saaaaaam wrote: post #45

Earlier quoted context omitted.

As a neutral participant I think “the hostility” is probably because of your condescending tone when you said “hopefully it helps your confusion”. Your initial article really didn’t say anything about people being re-incarcerated for these sorts of errors. I really want to say “maybe you got CONFUSED and posted the wrong one!” but that would be snotty and condescending too. But maybe you posted the wrong one to begin…

That's totally fair, I shouldn't have said it like that!

You seem to care a lot about these issues, and probably have real face-to-face experience with the victims of that.

Problem is though that this feeling type of empathy makes you not the best advocate for them - as you can see here, where (on a platform with worse rules than HN) a flamewar would've broken out over not everyone being as emotionally involved.

We definitely need people like you, but we also need people like you to not be everywhere and scare/annoy people into not caring. Though, I also agree that scaring/annoying _into_ caring is also often required.

Idk. Activism is weird and hard and all.

Re: GPS glitched across the US by as much as 33 feet

#116

Post by guenthert »

ashleyn wrote: post #60
Quibblingeek wrote: post #40

Earlier quoted context omitted.

Maybe not intentionally (at least by the U.S. Government, but the consequences are far greater now. Now that GPS has subsumed a large part of air navigation as more VOR and ILS approaches at non-towered airports are being left to fall into disrepair, it forces more and more aircraft operating in instrument conditions to fall back to a navigation system that may not operate to the tolerances that you need to shoot an…

One of the reasons SA was discontinued was that if you knew the coordinates of a base station, you could correct for the error. Are airports not doing this already?

iiuc, this is differential GPS (DGPS) and not only airports are doing that. At least in Europe there are quite a few such transmitters, see https://de.wikipedia.org/wiki/Liste_von_DGPS-Sendern

Re: GPS glitched across the US by as much as 33 feet

#117

Post by saltwatercowboy »

hypfer wrote: post #113
iamshs wrote: post #48

Earlier quoted context omitted.

The story is about GPS errors which end up making life hell for people under monitoring since they end up generating a Police response. If 80% alerts were false, then an error like this can result in a surge of these alerts. It is an important story to tell.

[flagged]

They're already being punished. I don't agree with being punitive to make observers feel good. It's an error. What else do you need?

Re: GPS glitched across the US by as much as 33 feet

#119

Post by amelius »

chaps wrote: post #12

This is exactly the sort of thing that leads to people getting reincarcerated after their electronic monitoring devices mistakenly report them leaving their homes. Some reporting I did on the topic a few years back: https://chicagoreader.com/news/many-on-house-arrest-in-cook-...

I mean, you had the chance to leave the house, compensating for the GPS error. Why didn't you take that chance?

Re: GPS glitched across the US by as much as 33 feet

#120

Post by lazyasciiart »

dataflow wrote: post #97
chaps wrote: post #69

Earlier quoted context omitted.

They did, yes. I hope you have a better day.

Okay thanks, so here's what I don't understand. When there is video evidence that someone was in their house the whole time, and given that everyone who has used a GPS knows it can easily be inaccurate by 30ft, why in the world would the judge trust the ankle monitor accuracy over video footage they see with their own eyes that directly contradicts it? Something about this just doesn't seem very plausible, especially…

Everyone knows video footage can be faked. Why would the judge ever trust video provided by the defendant over serious professional technology like GPS? Might as well just take their word for it!

What’s funny here is that you are displaying misplaced trust in the justice system that exactly parallels my hypothetical judge’s misplaced trust in technology.

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