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Spot the Drowning Child (2015)

spotthedrowningchild.com

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Re: Spot the Drowning Child (2015)

#411

Post by wutbrodo »

dmos62 wrote: post #400
notafraudster wrote: post #323

Earlier quoted context omitted.

Let's say you roll a dice with 100 sides. If you roll a 1, you die. If you roll anything else, you live. We want to know the probability you will die if you roll the dice 100 times. One way we could do this is look at the probability you'll roll it on the first roll... then the probability you won't roll it on the first roll but you will on the second roll... and so on. But that's a lot of math. The probability of an…

Counter question. How to calculate how many tries it would take to reach a specific probability for an outcome? For example, how many times do I have to roll the dice to have 90% chance of death? Due to my field of work, I'd solve everything by bruteforce, but I wonder what a more elegant solution could be.

Just solve the equation above.

0.99^n = (1-0.9)

n*log(0.99) = log(0.1)

n = log(0.1)/log(0.99) = ~229

Re: Spot the Drowning Child (2015)

#412

Post by jhloa2 »

watwut wrote: post #386
smileysteve wrote: post #255

Earlier quoted context omitted.

> teaching 5 year olds the butterfly and other high energy/low safety strokes without teaching elementary backstroke, breaststroke, sidestroke. I am amazed at how few of my early millennial peers have never heard of the elementary backstroke.

I was never taught that and I am older than that and used to swim competitively. I never seen anyone swim that. Likely, it was never standard think to teach.

I don't think that I was ever explicitly taught it as a child but at some point I stumbled across it by accident it's one of my favorite ways to swim casually. As someone else mentioned above, it totally feels like a jellyfish swim :)

Re: Spot the Drowning Child (2015)

#413

Post by fenwick67 »

retsibsi wrote: post #380
fenwick67 wrote: post #260

Earlier quoted context omitted.

And every jungle is full of kookaburras

Hah, have you got an example of this one? It's a very distinctive sound so it would be hilarious to hear it over a shot of some obviously non-Australian jungle.

This is so common it's on TVTropes:

https://tvtropes.org/pmwiki/pmwiki.php/Main/JunglesSoundLike...

Re: Spot the Drowning Child (2015)

#414

Post by retsibsi »

fenwick67 wrote: post #413
retsibsi wrote: post #380

Earlier quoted context omitted.

Hah, have you got an example of this one? It's a very distinctive sound so it would be hilarious to hear it over a shot of some obviously non-Australian jungle.

This is so common it's on TVTropes: https://tvtropes.org/pmwiki/pmwiki.php/Main/JunglesSoundLike...

Wow, thanks. I'm not big on TV/movies but I'm surprised I missed this one completely.

Re: Spot the Drowning Child (2015)

#416

Post by dotancohen »

quickthrower2 wrote: post #278
dotancohen wrote: post #267

Earlier quoted context omitted.

A family friend drowned to death at a public swimming pool with two lifeguards and his mother present. He was 11 years old at the time. Never take your eyes off your kids.

That is terrible. If it is OK to ask... was there anything special about those circumstances, like was there a specific reason like he passed out first or got hit by something? Or was still learning to swim? Before I read this comment, 11 to me seems like an age where you can start thinking about not watching them, and when I was 12 I used to go to the pool with just friends.

I don't remember, I think that he may have dove into the shallow end. I'll ask the wife tomorrow, she remembers everything! The horrible thing is that the pool was crowded, and so many other children were playing within touching distance while he drowned.

Re: Spot the Drowning Child (2015)

#417

Post by wearcam »

yourapostasy wrote: post #48

While there are many machine learning-based drowning detection systems out there, I'm having a hard time finding solid information comparing their reaction time and accuracy rates to lifeguards. Does anyone have any solid research that they've found? I don't want to replace lifeguards or increase their workload by spreading them thinner, but want to find out if we complement them together whether or not it would incr…

There seems to be two broad categories of products: those for pools and those for beaches.

Here's a shortlist of systems for pools: Coral Manta, SwimEye, Mobotix, Axis, AngelEye, Argusmatik, Poseidon, Zwembadcamera, Optoswim, Dipsee A.I., and Lynxight Deep Vision.

For beaches there's: Milestone, Coastalcoms, etc., and two of the above companies also do beaches: Dipsee A. I., and Lynxight Deep Vision.

Re: Spot the Drowning Child (2015)

#418

Post by bradknowles »

1e-9 wrote: post #374
mygo wrote: post #363

Earlier quoted context omitted.

The lay on your back technique works for those who it works for, and it should absolutely be taught to everyone just so that whoever it works for knows about it and uses it when they find themselves in a situation when it could save their life. Less drowning in calm waters is a net positive. But there is a percentage of the population who can’t simply float. Some of us literally sink if we don’t swim. One time my fri…

Fat and air float. Muscle and bone sink. Your overall buoyancy depends on your particular combination of lung capacity, fat, muscle, and bone. Also, fresh water is not as dense as salt water, so it is more difficult to float in. Decomposition produces a variety of gases that increase buoyancy.

It’s not just bones and muscle. Fat has different densities, too.

I have very high density fat. Although I’m more than 100 pounds overweight, I still sink like a rock when I get into the pool and exhale. If I inhale a lot of air into my lungs, I can usually keep my nose and mouth barely above water, but not much more.

In contrast, my wife is also overweight, but her fat is low density. There is nothing I have found that is capable of making her sink.

The times we have gone snorkeling, I have no problems diving and I have to work to surface. But she can’t dive for love or money, although she can get her face fully under water.

Re: Spot the Drowning Child (2015)

#419

Post by bradknowles »

sixothree wrote: post #369
balls187 wrote: post #249

When I was 12, I went on a week long hike as a scout. We decided to swim across a lake, and 1/2 way through, I got tired, and tried swimming back, but couldn't. I remember having the presence of mind to yell out help before blanking out. My closest friend in the troop luckily turned around, swam back to and drug me back to shore. I was scared of the water after that, but some how ended up fighting my fear and earning…

My only take-away from this video is just how exhausting it is (to me as a non-lifeguard). It feels akin to driving on a busy roadway. Maybe you learn to size kids up, know better where to focus, who to keep track of, and what to look for. But still. Just going through four of those videos left me thankful it's not my primary responsibility. It did help. I never did learn CPR. Maybe this is the year.

I learned CPR back when you could get a lifetime certification.

A few years ago, I took a class taught through my employer at the time (VMWare) and got recertified. It had been more than thirty years, but not that much had changed.

CPR isn’t hard. Spotting the drowning person, that’s the hard thing.

Re: Spot the Drowning Child (2015)

#420

Post by bradknowles »

kubanczyk wrote: post #327
smileysteve wrote: post #255

Earlier quoted context omitted.

> teaching 5 year olds the butterfly and other high energy/low safety strokes without teaching elementary backstroke, breaststroke, sidestroke. I am amazed at how few of my early millennial peers have never heard of the elementary backstroke.

I just googled "elementary backstroke" and yeah... I'm in my forties, pretty proficient swimmer, and nobody ever showed it to me. I watch my kid's lessons and I'm sure I didn't see it being shown to them. They got into what I google as "backstroke" straight away, without the "elementary" phase.

When I took swimming lessons at the YWCA in Wilmington, NC (where they did after school daycare in the late 70s), I went all the way through their process. My next step would have been to get into SCUBA.

They never taught the “Elementary Backstroke” to us, even though this was Wilmington, NC and we were just fifteen minutes from the beach.

The backstroke I learned was more like the crawl, just done on your back. After a while, I stopped bothering to use my arms and did a lazy backstroke using just my legs. I could do that for hours on end. The lazy backstroke wasn’t YWCA approved, but it worked well in the ocean and in pools. The only danger was that you couldn’t see what you might be about to hit.

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