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What are you referencing? Everywhere it's installed officers find usefulness in triangulating where shots are popped off. The alternative is an extensive inves

What are you referencing? Everywhere it's installed officers find usefulness in triangulating where shots are popped off. The alternative is an extensive investigation which is difficult to determine the location, if not impossible. I don't mind these shot spotters being installed vs CCTVs as the microphones are really just tuned for gunshots and can only serve one purpose (in the current form)

meheleventyone 3y ago
It was widely reported a few years ago that the tech was pretty useless for triangulation amongst a bunch of other worrying behavior by the company and police themselves: https://www.techdirt.com/2021/08/26/chicago-pd-oversight-says-shotspotter-tech-is-mostly-useless-when-it-comes-to-fighting-gun-crime/ https://www.techdirt.com/2021/08/26/chicago-pd-oversight-say...
- theultdev 3y ago
  That article is quite a mess isn't it? Seems they found more of a problem with the Chicago PD than ShotSpotter. > If this result is attributable in part to missing or nonmatched records of investigatory stops that did take place as a direct consequence of a ShotSpotter alert, CPD’s record-keeping practices are obstructing a meaningful analysis of the effectiveness of the technology. Should have been the end of the article right there, but techdirt decided to write one anyway. And false positives really aren't that big a deal anyway. You get false police reports, at least with the sensors you can recalibrate and adjust.
  - meheleventyone 3y ago
    "The study, which reviewed ShotSpotter deployments for roughly 21 months (from July 1, 2019, through April 14, 2021) using data obtained from the City of Chicago, found that 89% of ShotSpotter’s reports led police to find no gun-related crime and 86% turned up no crime at all, amounting to about 40,000 dead-end ShotSpotter deployments." If only we took companies out to defend their product at face value we could waste even more time and resources!
    - theultdev 3y ago
      Yes and then they go to say there's missing data for them to attribute investigations to ShotSpotter due to CPD’s lack of record keeping. So much so that it's "obstructing a meaningful analysis of the effectiveness of the technology". Their words, not mine.
      - meepmorp 3y ago
        That would undermine the original point you made, though: > Everywhere it's installed officers find usefulness in triangulating where shots are popped off. At best, cops are going on 'feels' here because, presumably, the data aren't sufficient to provide a solid basis for analysis. Or the police are withholding data that proves the system works well, which prima facie seems unlikely.
        theultdev 3y ago
        I've only heard anecdotes of cops saying it worked well, and it does seem like a good investment and an achievable goal. I don't know what the real numbers are, but from that article it seems noone does... A proper reporting of numbers would be nice.
    - kube-system 3y ago
      You wouldn't want to waste officers time responding to those calls, but sending an automated surveillance camera is a different use of resources. Most surveillance cameras spend 99.99+% of their time watching no crime happening. I would rather the cameras go to the gunshot noises than stay bolted to a pole outside my house, which is where they are now.
      - meheleventyone 3y ago
        Those systems wouldn't be that automated, you'd need a whole fleet of techs and others to maintain them. And why to chase the 10% change the alert is anything at all. To me it sounds like the tech improvement needed in this situation is being applied in the wrong place.
- crazygringo 3y ago
  Yeah, I'd be very surprised to see triangulation work well. When you walk around neighborhoods where all the buildings are four to six stories tall, you can be totally deceived about what direction sounds are coming from, because there are so many sonic reflections. If you built towers for microphone above the cityscape you could get an accurate triangulation, but obviously nobody's doing that.
  - oh_sigh 3y ago
    You only have two ears, very close together. Would it be confusing if you had 20 ears spread out all over the neighborhood?
    - crazygringo 3y ago
      Yes, because the signal will be equally confusing. A sensor 4 blocks away will often record a much louder sound than one half a block away, because of buildings that are variously absorbing or reflecting sound. That makes triangulation utterly useless. You can localize to maybe a 20 square block area, but that's not a whole lot for cops to go on.
      - oh_sigh 3y ago
        Loudness isn't too important - timing is. Even with the 4-block-away mic being on a direct line of sight, and the half-block-away mic being around a corner, the half-block-away mic will perceive the event .5s or more before the 4-block away mic does.
      - anigbrowl 3y ago
        You're wrong about this. I have no particular love for shotspotter but I do have many years of pro experience as an audio engineer and understand FFTs inside out. Pathological reflections (where the echo is louder than the direct sound) exist of course, but they're rare; and when you're recording from fixed locations you can just map those problems out, because buildings don't move around much. You can always triangulate; you have to add more sensors and compute, but both of those are relatively cheap.
deleted 3y ago
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meheleventyone 3y ago

It was widely reported a few years ago that the tech was pretty useless for triangulation amongst a bunch of other worrying behavior by the company and police themselves: https://www.techdirt.com/2021/08/26/chicago-pd-oversight-says-shotspotter-tech-is-mostly-useless-when-it-comes-to-fighting-gun-crime/ https://www.techdirt.com/2021/08/26/chicago-pd-oversight-say...

theultdev 3y ago
That article is quite a mess isn't it? Seems they found more of a problem with the Chicago PD than ShotSpotter. > If this result is attributable in part to missing or nonmatched records of investigatory stops that did take place as a direct consequence of a ShotSpotter alert, CPD’s record-keeping practices are obstructing a meaningful analysis of the effectiveness of the technology. Should have been the end of the article right there, but techdirt decided to write one anyway. And false positives really aren't that big a deal anyway. You get false police reports, at least with the sensors you can recalibrate and adjust.
- meheleventyone 3y ago
  "The study, which reviewed ShotSpotter deployments for roughly 21 months (from July 1, 2019, through April 14, 2021) using data obtained from the City of Chicago, found that 89% of ShotSpotter’s reports led police to find no gun-related crime and 86% turned up no crime at all, amounting to about 40,000 dead-end ShotSpotter deployments." If only we took companies out to defend their product at face value we could waste even more time and resources!
  - theultdev 3y ago
    Yes and then they go to say there's missing data for them to attribute investigations to ShotSpotter due to CPD’s lack of record keeping. So much so that it's "obstructing a meaningful analysis of the effectiveness of the technology". Their words, not mine.
    - meepmorp 3y ago
      That would undermine the original point you made, though: > Everywhere it's installed officers find usefulness in triangulating where shots are popped off. At best, cops are going on 'feels' here because, presumably, the data aren't sufficient to provide a solid basis for analysis. Or the police are withholding data that proves the system works well, which prima facie seems unlikely.
      - theultdev 3y ago
        I've only heard anecdotes of cops saying it worked well, and it does seem like a good investment and an achievable goal. I don't know what the real numbers are, but from that article it seems noone does... A proper reporting of numbers would be nice.
  - kube-system 3y ago
    You wouldn't want to waste officers time responding to those calls, but sending an automated surveillance camera is a different use of resources. Most surveillance cameras spend 99.99+% of their time watching no crime happening. I would rather the cameras go to the gunshot noises than stay bolted to a pole outside my house, which is where they are now.
    - meheleventyone 3y ago
      Those systems wouldn't be that automated, you'd need a whole fleet of techs and others to maintain them. And why to chase the 10% change the alert is anything at all. To me it sounds like the tech improvement needed in this situation is being applied in the wrong place.
crazygringo 3y ago
Yeah, I'd be very surprised to see triangulation work well. When you walk around neighborhoods where all the buildings are four to six stories tall, you can be totally deceived about what direction sounds are coming from, because there are so many sonic reflections. If you built towers for microphone above the cityscape you could get an accurate triangulation, but obviously nobody's doing that.
- oh_sigh 3y ago
  You only have two ears, very close together. Would it be confusing if you had 20 ears spread out all over the neighborhood?
  - crazygringo 3y ago
    Yes, because the signal will be equally confusing. A sensor 4 blocks away will often record a much louder sound than one half a block away, because of buildings that are variously absorbing or reflecting sound. That makes triangulation utterly useless. You can localize to maybe a 20 square block area, but that's not a whole lot for cops to go on.
    - oh_sigh 3y ago
      Loudness isn't too important - timing is. Even with the 4-block-away mic being on a direct line of sight, and the half-block-away mic being around a corner, the half-block-away mic will perceive the event .5s or more before the 4-block away mic does.
    - anigbrowl 3y ago
      You're wrong about this. I have no particular love for shotspotter but I do have many years of pro experience as an audio engineer and understand FFTs inside out. Pathological reflections (where the echo is louder than the direct sound) exist of course, but they're rare; and when you're recording from fixed locations you can just map those problems out, because buildings don't move around much. You can always triangulate; you have to add more sensors and compute, but both of those are relatively cheap.

deleted 3y ago

[deleted]