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> Also worth considering is that, even if higher limits reduce the rate of accidents, accidents at higher speeds are almost universally more severe.

Obviously this is true, and especially important at low speeds, but I wonder how much difference there is between 70 and 80 — I would have assumed they are both typically fatal


The energy is exponential. It takes 30% farther to stop going 80 than it does going 70.

One of my favorite trivia is the scenario that a car going 50 mph sees an obstruction in front and slams on its brakes and stops just in time just tapping it. A car next to him going 70 mph sees the same object, has faster reflexes, and hits his brakes at the exact same spot of the road. He slams into the object at 50 mph.

Just the difference between 70 and 80 is the energy of going almost 40 mph.


> The energy is exponential.

No, kinetic energy is only quadratic in the velocity, E = ½ mv².

https://en.m.wikipedia.org/wiki/Kinetic_energy


You're correct. My wording was off.


Another related pet peeve is when I see cyclists going the wrong way in a bike lane. On a 40 mph road a cyclist has a differential with traffic of 20-25 mph. An accident would be serious by likely non-fatal. When you ride the wrong you you add the speeds and make nearly all collisions fatal.


> The energy is exponential. It takes 30% farther to stop going 80 than it does going 70.

That's when the issue is stopping distance.

The issue on highways is that you have, for example, two cars in the left lane going 55 MPH and a third approaches going 70 MPH. One of the slower cars sees this and moves over but only at the same time as the faster car is changing into the same lane to pass on the right, so now both lanes are blocked, the faster car hits one of them and they're both edged off the road into a stationary object at highway speeds.

Does it matter if they hit the stationary object with significantly more energy? Probably not; dead is dead.


I guess that's theoretically possible, but even in that rare case, people are going to break if they hit someone. Driving too slow causes some accidents but they rarely lead to deaths. AFAIK, driving too slow is such a minor safety issue that no study has been carried out to ascertain exactly how bad it is though.


The trouble with that one is that it's the one caused by people driving too slow, and isn't rare. When people are driving at significant speed differentials to each other, it causes a lot of lane change maneuvers. Which are dangerous because each one is a chance to move into a lane without realizing there is someone in your blind spot, or that the new lane has an obstruction ten feet in front of you, or focus your attention on what's happening in the lane you're intending to change into and fail to notice an immediate hazard in the lane you're still in. So you get more accidents, and those accidents are still happening at highway speed.

Meanwhile a significant proportion of accidents happen not because you couldn't stop fast enough but because you couldn't stop at all. Another driver side swipes you and rams you off the road and you're now three feet from a head-on collision with a utility pole; if you can even get your foot to the brake before impact it's not going to save you. You're driving on an apparently clear road in winter and come across a patch of black ice; your brakes have no effect and you're hitting whatever's in front of you at full speed. It's night, you're tired and you only realize there is a completely dark disabled vehicle in one of the travel lanes when you smash into it.

In cases like this the difference between 30 MPH and 50 MPH can mean a lot, but the difference between 55 MPH and 80 MPH is basically just "you're still dead".


Right the energy is exponentially, but I’d claim that fatalities are saturating.


technically it's the EU working hours directive that's binding (or being opted out of) in the UK


It's correct that it was the Working Time Directive that required the UK to add it to UK law in the first place (over the strident objections of the Tory government at the time) but it is the Working Time Regulations Act 1998 that provides this regulation in the UK, and since Brexit the EU Working Time Directive 2003 has no legal force in the UK.


EU directives never had any direct legal force in the UK, or any other member state. The point of the directive is to say "all EU members need national legislation which meets these standards". It's then up to the member states to implement national laws using their own unique systems which meet the requirements of the directive.

As you said, the Working Time Regulations Act 1998 is the UK law implementation of the EU Working Time Directive 2003.


> when they're the largest video game distribution platform on PC

And just adding on to this, they also a have a stable of some of the most successful (and presumably lucrative) games released in the last 20 years: dota 2, cs:go (admittedly, not in-house to start), TF2.

Granted, a lot of these are towards the autumn of their lifecycles, but it can't be discounted.


You also can use the fact that for any distribution, the median is never further than 1SD away from the mean.


Why would anyone take the other side of this bet? It's an incredible financial instrument, that anyone on the buyside would buy in an instant (as formulated -- ignored fees/tcosts etc).


> Why would anyone take the other side of this bet?

People accept this bet every single day… when they buy actively-managed funds.

Actually they accept a worse bet. Instead of taking 100% downside risk and being taxed on anything above the index, they’re taxed on both gains and losses.

You’re right that it’s an incredible financial instrument. Actively-managed funds are extremely profitable… for fund managers, who get paid out of investors’ assets in bad years and also get to skim off the gains in good years.


If I can consistently make more than 10% on your money, I'll take the other side.


If you can consistently make more than 10% you don’t need to hamstring yourself with this terrible deal, you can just get investment on typical terms.


If I can consistently make 30%, this terrible deal will make me 20%, whereas the typical terms of management fees will make me 5%.


If you can consistently make 30%, a bank loan will make you 24%.


Fair point. I don't know why BlackRock did it, then.


> Waking in the middle of the night is caused by stress around a problem

I don't think this is universal. For example: rotating shift workers can have a mostly physiological insomia, due to various disrupted rhythms.


Is the correct number 0 or >1?


Note my use of the term "heuristic" and not "algorithm." There is not a correct number. The correct approach is to fiddle with the parameters; record good populations; occasionally restart from scratch... we call this "hyperparameter tuning" to make ourselves feel better about the process.


Why is this conspiratorial? It’s simply a theory, no?


Not in the UK (passthrough sugar tax)


sometimes also 'niner' instead of 'nine' for similar reasons.


In standard aviation phraseology it's "fife" for the number five and "niner" for the number nine, to avoid confusing between them.


ICAO standard prescribes "fower" as four (making it two syllables), as well as all the others that have been cited (tree/three, fife/five, niner/nine).


And „tree“ instead of „three“.


You sure that wasn't just an Irishman doing the countdown?


„The ICAO, NATO, and FAA use modifications of English digits as code words, with 3, 4, 5 and 9 being pronounced tree, fower (rhymes with lower), fife and niner. The digit 3 is specified as tree so that it is not pronounced sri; the long pronunciation of 4 (still found in some English dialects) keeps it somewhat distinct from for; 5 is pronounced with a second "f" because the normal pronunciation with a "v" is easily confused with "fire" (a command to shoot); and 9 has an extra syllable to keep it distinct from the German word nein "no". (Prior to 1956, three and five had been pronounced with the English consonants, but as two syllables.?“

https://en.m.wikipedia.org/wiki/NATO_phonetic_alphabet#Pronu...


Jamaican?


They used to say fiver instead, as well


That sounds even more like "fire"!


Is that meant to sound less like “fire”??


No, fiver is occasionally used by beginning aviation students though in confusion (DAMHIK).


I bet they didn't.


I am not claiming it was standard, only that it was used. You can hear it in old WWII footage.


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