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Car alarms and smoke alarms: tradeoff between sensitivity and specificity (2012)

blog.danslimmon.com

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Re: Car alarms and smoke alarms: tradeoff between sensitivity and specificity (2012)

#41

Post by justin_oaks »

rtkwe wrote: post #2

It's a constant pain of mine to try to get people to stop having business as usual or successfully completed $PROCESS emails come out of our batch processes on our teams at work. They absolutely drown my inbox so I'm forced to filter them then the actual failures get buried in the unchecked "batch spam" folders.

I had a boss who had an inbox with literally hundreds of thousands of unread emails. A good chunk of those emails were "success" messages from batch processes.

It's quite correct to send a "success" message when a batch process is completed successfully, but it's quite wrong to send that message to a human. It should be sent to a machine that should translate a missing success message into an error message/alert for humans to respond to.

For example, I have a set of nightly backup jobs. The last step of each backup process is to send a success message to my monitoring system. I only get a "Missing Backup" alert when the monitoring system detects that it didn't receive the success message it expected for a particular backup.

My old boss didn't seem to understand the concept that people don't generally notice missing messages. Or he was too lazy/incompetent to use a monitoring system that could translate gaps in successes into errors.

Re: Car alarms and smoke alarms: tradeoff between sensitivity and specificity (2012)

#42

Post by Eji1700 »

birdyrooster wrote: post #37
dahfizz wrote: post #35

Earlier quoted context omitted.

Yeah, I can't remember the last time I heard a car alarm.

Visit a city

I live in one with more than 2 million people and it's something that I have to think hard about to remember the last time I heard one go off.

Longer if I have to think of one that went off and wasn't some form of 'oh shit oh shit oh shit, wrong button' reaction from the person trying who accidentally turned it on.

Re: Car alarms and smoke alarms: tradeoff between sensitivity and specificity (2012)

#43

Post by GuB-42 »

sammalloy wrote: post #23

The entire car alarm industry is a scam, promoted by Republican congressman Darrell Issa. It has seriously disrupted our lives in every way imaginable and has drowned out the beauty of nature. I can’t think of a single car that has been protected by a car alarm since they were invented. They are useless and should be banned for the health and safety of mitigating noise pollution.

> I can’t think of a single car that has been protected by a car alarm since they were invented.

Many insurance companies offer lower premiums if you install a car alarm. So I guess they work at least a little, otherwise they wouldn't lower their premiums.

It may not actually stop a thief, but it may get a thief to chose a car that doesn't have an alarm, or maybe it is just a correlation, but there is at least something.

Still, I think they should be made illegal, they are a nuisance, there are already laws against making excessive noise and car alarms should be included. And if they create an arms race, by getting thieves to prefer cars without alarms, that's even more reason to ban them.

Re: Car alarms and smoke alarms: tradeoff between sensitivity and specificity (2012)

#44

Post by justin_oaks »

hevans66 wrote: post #15
rtkwe wrote: post #2

It's a constant pain of mine to try to get people to stop having business as usual or successfully completed $PROCESS emails come out of our batch processes on our teams at work. They absolutely drown my inbox so I'm forced to filter them then the actual failures get buried in the unchecked "batch spam" folders.

My pet peeve is these $PROCESS notifications that go to slack channels. I worked at a company that had an #engineering_humans slack channel because we got chased out of #engineering by bots.

I'm fine if they go to THEIR OWN slack channel. Then I can mute or leave that channel.

Of course, it's a different problem if those notifications have a mix of actionable and non-actionable messages (e.g. both success and error messages). Then it's a signal/noise problem.

Re: Car alarms and smoke alarms: tradeoff between sensitivity and specificity (2012)

#45

Post by bluGill »

riceart wrote: post #38
bluGill wrote: post #26

Earlier quoted context omitted.

The law requires you have both types of good reason. Either alone will detect less than half of all house fires. Dual sensors are not and gated. While nobody will admit what algorithm they use, they detect most fires unlike the single sensor type.

Lol “the law” .. what law? Maybe in some dumb ass jurisdiction - but you’re a bit full of yourself if you think where you happen to live is “the law”.

Us fire code, though inspectors often don't check.

Re: Car alarms and smoke alarms: tradeoff between sensitivity and specificity (2012)

#46

Post by Syonyk »

bluGill wrote: post #45
riceart wrote: post #38

Earlier quoted context omitted.

Lol “the law” .. what law? Maybe in some dumb ass jurisdiction - but you’re a bit full of yourself if you think where you happen to live is “the law”.

Us fire code, though inspectors often don't check.

As far as I can tell, it's state by state, so... you want to cite some sources?

Re: Car alarms and smoke alarms: tradeoff between sensitivity and specificity (2012)

#47

Post by HPsquared »

izacus wrote: post #31
jimbob45 wrote: post #29

Earlier quoted context omitted.

For poor people whose ability to live depends on having a car, car alarms must be at least sort of useful to know if your car is being stolen at night. I’m sure they’re just a noisy inconvenience to the wealthy though.

Does the alarm ever prevent theft?

Hard to prove empirically either way, I think. Even if they do, it's then arguable if this is worth the noise pollution etc. Probably depends on the circumstances in any case, so any empirical result would be too specific to be of any use. Science!

Re: Car alarms and smoke alarms: tradeoff between sensitivity and specificity (2012)

#48

Post by riceart »

bluGill wrote: post #45
riceart wrote: post #38

Earlier quoted context omitted.

Lol “the law” .. what law? Maybe in some dumb ass jurisdiction - but you’re a bit full of yourself if you think where you happen to live is “the law”.

Us fire code, though inspectors often don't check.

Oh that I happen to know something about - you’re making stuff up. I’ve got NFPA 72 right here if you want to point out where this alleged requirement for “multi-sensor” detector exists.

In fact there are specific requirements to use only single sensor type alarms - such as near cooking equipment.

You can go the the NFPA website though where the publicly facing website notes they are “recommended”. They are not and have never been required.

Re: Car alarms and smoke alarms: tradeoff between sensitivity and specificity (2012)

#49

Post by bdamm »

Both of these are exactly the kind of problem where our AI future is going to deliver cost effective modern alternatives. Primitive sensors wake up more sophisticated analyzers and use deep sensors (including video) to determine if there is a real problem.

Witness companies like Rivian triggering car alarms on aggressive behavior detected from ML on video. Don't even need to touch the car.

Re: Car alarms and smoke alarms: tradeoff between sensitivity and specificity (2012)

#50

Post by asdff »

Eji1700 wrote: post #42
birdyrooster wrote: post #37

Earlier quoted context omitted.

Visit a city

I live in one with more than 2 million people and it's something that I have to think hard about to remember the last time I heard one go off. Longer if I have to think of one that went off and wasn't some form of 'oh shit oh shit oh shit, wrong button' reaction from the person trying who accidentally turned it on.

All it takes is one neighbor to move in with a finicky alarm and a street parking situation to ruin the peace and quite of this amazingly rare statistical anomaly you reside in.
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