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pg314

1,522 karma · joined February 28, 2014

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pg314··on Why America's economy is soaring ahead of its rivals
> An iPhone or a Toyota Corolla costs the same in the US as it does in China.

A maxed out iPhone costs RMB 13999 in China, which is about USD 1925. The same iPhone costs USD 1599 in the US. In Brazil it costs the equivalent of USD 2565. PPP is still very much relevant.

pg314··on The size of BYD's factory
> The paper suggests biking only 118 days per year. The car ownership costs are not "saved" - the projected savings are wrong.

Were does it suggests that? The number 118 doesn't appear anywhere in that document.

> Ownership car costs are 0.167/km and savings by riding a bicycle are 0.349/km.

Where do you get these numbers from?

> carrying capacity (groceries, children, sports equipment, etcetera)

I do all grocery shopping for a family of four with a cargo bike. I pick up and drop off children in the cargo bike. You can think up objections all day if you want, but that doesn't change the fact that some people succeed in living car-free.

Nobody is forcing you to take a bicycle. Even if you personally don't like cycling, you should still encourage others to: every cyclist you see riding around is one less car stuck in traffic with you.

> And I'd like to see other costs of cycling (wet weather gear, helmets, locks) included.

Then you're in luck. On page 24, they include a budget of 117 EUR for gear and accessories.

pg314··on The size of BYD's factory
> It is outrageously expensive.

Quite the opposite.

> Can you point me to a report that has a cost/benefit analysis of adding bike lanes for a city? A city that isn't "ideal" for cyclists...

https://www.benelux.int/wp-content/uploads/2023/03/Report_Cy...

pg314··on Love of cargo bikes is changing how we deliver goods in our cities
> It’s 100% that they cost as much as a decent used car.

Apples and oranges. You can get cargo bikes second hand too.

pg314··on Love of cargo bikes is changing how we deliver goods in our cities
Yes, I own both.

The three-wheeled ones take some getting used to. You can't take turns at a high speed or you'll tip over. They are nice when you are standing still, because they stay up-right. They are easier to turn-around on foot: the front wheels are closer to the centre of mass, so you can easily lift the back wheel and swing it around.

The two-wheeled ones are faster, and handle more like a normal bike. When fully loaded (100+ kg) they take some effort getting them on the stand. They are clunkier to turn around.

I prefer the two-wheeled ones.

pg314··on Harnessing heat from wastewater
No, it preheats the cold water connected to your shower. Warmer cold water means you need less hot water to achieve the same temperature in the shower.
pg314··on S.F. says incidents by Cruise, Waymo driverless taxis are ‘skyrocketing.’
Why not? I do.
pg314··on All the arguments against EVs are wrong
Why would the number of cars grow by 5% for the next 100 years? Currently there are 1.4 billion cars. Projections say the world population will peak at 10 billion. Even if everyone would have a car, that’s only a sevenfold increase.
pg314··on The world’s oldest ultramarathon runner is racing against death
Adidas adizero adios (the old ones, before they grew a thick sole). Allbirds had a nice shoe they developed together with Adidas, which is discontinued now. Some Nike free, but they have too thick a sole for my taste… At the moment, the shoes I like best are discontinued. Luckily I have a couple of pairs in reserve. You know the writing is on the wall when they are heavily discounted; good time to buy a couple of pairs.

By the time I need to buy new ones, fashions will hopefully have shifted back…

By the way, when I say fall apart, I mean it literally: toes peeking out and losing bits of the sole.

I also rotate the shoes: the older ones are for the easy runs, the newer ones for tempo or intervals.

pg314··on The world’s oldest ultramarathon runner is racing against death
> Second important thing are fresh shoes. No more than 600km.

That’s what shoe companies want you to believe. I just run until they fall apart. A couple of thousand km easily.

2:45 marathon at 41.

pg314··on Bean leaves don’t let the bedbugs bite by using tiny, impaling spikes (2013)
A Google search of 'bedbug' and any major city in Europe will return plenty of hits.
pg314··on The “Build Your Own Database” book is finished
Maybe I'm missing something, but after a cursory glance, I can't find any place where that library does an fsync() call. How does it handle durability?
pg314··on The Coming Technological Singularity (1993)
> If, say, ChatGPT is superintelligent, the only way it can hurt you is through insult or persuasion.

People are already hooking up ChatGPT to the command line of their computers and giving it access to the internet. There are plenty of ways a super-intelligent AI would be able to wreak havoc.

pg314··on How can we stop the CO2 that plants store from leaking back into the air?
The problem is far from solved. It's not enough that carbon emissions will peak soon. They need to come down fast. And we do not have a decade or two.
pg314··on India's Forgotten Mansions
> Ultimately not much you can do with money except spend it on things you enjoy

You could spend it to help other people, if you’re out of ideas.

pg314··on The electric vehicles we need now are e-bikes (2022)
> It’s not just that it’s a big spend, but it’s a big spend on something 75% of people don’t use even if you did it.

Are we to take your word that 75% of the people won't use it? Countries like the Netherlands and Denmark show that if you build bike infrastructure, people will use it. And the health and environmental benefits are enormous.

And even if only 25% of the people use it, shouldn't they get 25% of the spend?

> Sure if you are young and live in San Francisco or New York City, this might seem reasonable. But for the other 80% of America, who are old enough that simply falling off of a bike could cause real injuries, or live somewhere not dense enough to really get anywhere this way, or don’t want to ride a bike in the snow, especially in a city that may not be particularly great at removing it (which is almost all but the biggest of them)

80% of the population in the US lives in cities. The median age is 39. So, no way 80% of the population fit your description. In cycling countries like the Netherlands and Denmark, even 80-year-olds cycle.

> or don’t want to ride a bike in the snow, especially in a city that may not be particularly great at removing it

Ask the Finnish how they do. They have no problem to cycle in the snow. You can change the way your city manages the snow.

> Cars may be environmentally awful, but they’re great in basically every other way,

1.3 million people get killed worldwide by cars every year. A multiple of that get maimed. I wouldn't call that basically great. If you count the time spent in traffic, you are wasting millions of lives more each year.

Electrifying has huge environmental costs. E.g. the Polestar 2 has a lifecycle cost (over 200.000kms) of 50 tons of CO2e compared to 58 tons for a Volvo XC40 ICE [1].

[1] https://www.polestar.com/dato-assets/11286/1630409045-polest...

pg314··on Cyclists now outnumber motorists in City of London
I cannot speak for the safe part, but here in Belgium plenty of people leave their Urban Arrows outside (with a rain cover).
pg314··on Cyclists now outnumber motorists in City of London
It's true that you'll get more exercise if you do the same trip on a regular bicycle. But according to [1], e-cyclists cycles more and longer than regular cyclists. End result is that they exercise about as much.

[1] https://www.sciencedirect.com/science/article/pii/S259019821...

pg314··on Cyclists now outnumber motorists in City of London
Do a google image search for 'Dutch on bicycles'. None of those people in the pictures need to change or shower after their ride. Same thing were I live. We only wear special cycling clothes if we go out cycling on a road bike or mountain bike in the weekend. And of course then you need to shower afterwards.
pg314··on Banking in uncertain times
> Okay, weird bit of pedantry - pretty sure that if a math test asks you to ‘calculate the product of 127 and 954’ you wouldn’t get many marks for answering ‘about 100,000’, but feel free to staple a copy of the dictionary definition to your exam paper and see if that works for you.

I wasn't taking a math test. I was saying something about NPV using a common meaning of an English word. You chose to ascribe a different meaning to that word, and pedantically - and incorrectly - tried to correct me.

pg314··on Banking in uncertain times
> You can’t calculate NPV. You can only estimate it.

According to Merrian-Webster [1]:

calculate: 1 b: to reckon by exercise of practical judgment : ESTIMATE

[1] https://www.merriam-webster.com/dictionary/calculate

pg314··on Banking in uncertain times
> In real terms, you will get back exactly a hundred million.

In nominal terms. In real terms you have to adjust for inflation. [1] is a starting point if you want to read more.

> As long as you hold to maturity, the number of dollars does not change.

A dollar now is not the same as a dollar 10 years from now. [2]

[1] https://en.wikipedia.org/wiki/Real_versus_nominal_value_(eco... [2] https://en.wikipedia.org/wiki/Time_preference

pg314··on Banking in uncertain times
> If those assets are in your hold to maturity portfolio, they are still worth $100m.

They are still worth $100m at maturity. $100m in ten years is (usually) worth less than $100m now. Do you really want to pretend that a ten year bond you purchased when inflation and the interest rate were near zero, is worth the same when inflation and the interest rate go up to say 10%? What about inflation of 100%? In nominal terms you’ll get back your capital, but in real terms you will get back only one thousandth.

To correctly value them now you need to calculate the NPV.

pg314··on SVB shows that there are few libertarians in a financial foxhole
> The amount it will pay at maturity remains unchanged and in 10 years it will be worth exactly the same no matter what the financial history that brought it to that point was.

Wrong. You're forgetting about inflation. Interest rates increased because inflation spiked. In 2022 alone, that nominal payout at maturity has lost 8% of its real value.

pg314··on SVB shows that there are few libertarians in a financial foxhole
> The bonds are worth exactly what they thought they'd be worth if held.

That's wrong. A 10 year treasury bond with a .60% you bought in august 2020 is now worth significantly less. Whether you hold it or not is irrelevant. If you disagree, I'm willing to give you one, if you give me a 7 year treasury bond at the current interest rate of 3.86%.

pg314··on SVB shows that there are few libertarians in a financial foxhole
> If you hold a bond to maturity you get it’s NPV. Valuing it at NPV vs mark to market

The NPV calculation should use the market intrest rate. If you use that, it should be pretty much the same thing: an efficient market should value a bond at its NPV.

However, they were allowed to value HTM (hold to maturity) bonds at face value. That is just non-sensical from an economics perspective and just hides losses.

pg314··on “Clean” code, horrible performance
>It's not really possible to write hand-coded assembler that's faster anymore.

That is wrong. Just because you didn’t succeed in writing faster code in one case, doesn’t mean it’s impossible. See e.g. [1] on why the Lua vm is written in assembly. It’s from 2011 but not much has changed in the meantime.

[1] http://lua-users.org/lists/lua-l/2011-02/msg00742.html

pg314··on A runner who leads every pack and then vanishes
> That is bad for your knees.

[Citation needed]

I wouldn't recommend speeding up on the downhills for beginning runners. But if you're well conditioned, running slightly faster on the downhills in a relaxed way won't hurt your knees. It all depends on the slope of course. On very steep hills, it simply isn't be possible to run fast downhill.

> I highly recommend the book Born to Run by Cristopher McDougall.

It's an entertaining read, but that's about it. The science is to be taken with a large grain of salt. (I've run more than 50000 km since reading it.)

pg314··on Production Twitter on one machine? 100Gbps NICs and NVMe are fast
> No one has said Twitter operates entire data centres.

They do though. 3 in the US alone (https://www.datacenterdynamics.com/en/news/report-elon-musk-...).

pg314··on Production Twitter on one machine? 100Gbps NICs and NVMe are fast
Could you give an insight into the reasons that such a system never replaced the existing implementation?
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