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Pokémon Go Is Teaching Americans the Metric System (gizmodo.com)
206 points by ahmedfromtunis on July 23, 2016 | hide | past | favorite | 161 comments



I always approximate the number of kilometers in a mile to phi (which it is pretty nearly - it is about 5% out), then you can use the Fibonacci series to convert between them.

1 1 2 3 5 8 13 21 ...

So if you want to know what 5 km is, find 5 in the Fibonacci series and the number of miles is the one just below - 3 in this case. Just use the next higher for miles -> km, eg 5 miles is 8 km.


It's easier for arbitrary values to multiply by 1.6 imho. That's easy. Take the original value and divide by two. Then right-shift the original value by one decimal place. Add the three and there's your answer. To go the other way, multiply by 0.6 (add the half and tenth values above).

Example: How much is 37 miles in km? 37 + 3.7 + 18.5, or 59.2.

If you don't mind a really rough guess, multiply by 1.5.


Fibonacci approach can still be used for pretty much any number.

37 = 3 + 13 + 21

Find equivalents in series

3->5, 13->21, 21->34

Add up: 5+21+34 = 60


This isn't easier than multiplying by 1.6 at all, but it's also new to me and really awesome. Thank you (and the grandparent poster) for mentioning this!


Divide by six, multiply by ten. And vice versa. Quicker in the head when an approximation is required.


that sounds a lot harder than multiplying by 1.6


Im not sure which I appreciate more. An overengineered solution that probably cane about by some eureka type observation. Or the cold calm criticism that Ive learned to appreciate by making too many over engineered solutions


I value that criticism a lot, particularly when it follows fun thoughts like "why don't we write our own consensus? Raft isn't too bad, right?" In the words of Wally[0], the urge eventually goes away.

[0]: http://dilbert.com/strip/1995-01-28


You're both upvoted. I'm going to try the Fibonacci version for a while.

(Though perhaps as is suggested with languages, it's better to start applying the new system directly, instead of performing a conversion step first.)


Yes! What is a meter? One Yard! 1km = 10 football fields (no end-zones)

I find that meters are better for thinking about walking measures, why does our system even have a yard? Think in units, metric is good. I learned this in American Public School. I was very lucky.


It's a perfectly well-defined number system: https://en.wikipedia.org/wiki/Zeckendorf%27s_theorem


Memorizing a sequence of ten numbers (or so) sounds way easier than multiplying by 1.6 (or .62) without whipping out a calculator.


If you think of 1.6 as 1 + 1/2 + 1/10, then multiplying by it is pretty easy. For example, 34 x 1.6 = 34 + 17 + 3.4 = 54.4.

The exact conversion is 1.609344, so to two places it is 1.61. That's only slightly harder than 1.6. Think of it is 1 + 1/2 + 1/10 + 1/100. So for my prior example, 34 x 1.61 = 34 + 17 + 3.4 + 0.34 = 54.74.

The operations needs, taking 1/2, 1/10, and 1/100 of the original value are generally easy in your head. The hardest thing is just keeping track of the running sum as you do that.

If you want to go one step farther, you could add a -1/1000 term to bring it to 1.609 but that is probably overkill in most circumstances. Even 1.61 is probably overkill.


It's not that hard. And if it is, add 50% and a fudge factor.


I multiply by 1.5. Like "metric pounds" (500g) it's close enough.


In china, they use a unit (the 斤 jin) that is equal to 500g. (Now. Historically it would have been something close.)

I got a shocked reaction "you look much smaller!" from someone when I just reported my weight in pounds as weight in 斤. I guess the lesson is it's not "close enough" when people are already sensitive to a particular scale.


I think you are correct, but I think humans are not as sensitive to distance measurements. If you sprint, and have a 100 yard and 100 meter dash time... Well certainly! If you want to say we just walked 100m to the car, not so much.


Yes, close enough*

*except for when it's not, of course :-)

Loaves of bread in Japan are still sold using 斤 (kin). A standard loaf is one "bread kin" which is defined as 340g or more.


multiplying with 1.6180339887.. you ment?


Alternatively: multiply by ten, convert to hex, and read off as a fixed point value with 4 fractional bits.

1km = 10 = 0xA = 10/16 mile = 0.625 miles (actual: 0.621371)

2.5km = 25 = 0x19 = 1 and 9/16 miles = 1.5625 miles (actual: 1.55343)

(If it isn't obvious where the 1.6 went, you probably won't regret figuring it out.)


for me, it's easier to think of it this way:

1 mi ~ 8/5 km, so v miles ~ v x 8 / 5 kms, and w kms ~ w x 5 / 8 miles.


Or, just visualize your car's speedometer: 100kph=62mph and 100mph=160kph; approximate from there.

http://a57.foxnews.com/global.fncstatic.com/static/managed/i...


I love this solution. It doesn't help you answer the question "how far is a 10K" though. If you factor into 5 and 2 and use your method on each factor, you get 3mi which is pretty wrong.


Hmm

10 km = 2 * 5 = 2 * 3 miles = 6 miles which is pretty close

The way you seem to have done it: 10 km = 1 mile * 3 miles And your units have changed so this can never be right.


Before I had it memorized, I tried with "11.66" which breaks down into two parts ("1:1.6" and "1.6:6")

1 mile = 1.6 kilometers

1.6 gallons = 6 liters


It is interesting that it would be trivial for them to localize the units, it seems like they specifically didn't.

As a datapoint of one I was fine with thinking in kilometers because those are generally the units I use when running (you don't typically enter 3.11 mile races).

My sense of metric vs. imperial is that metric will seep into public conscious slowly over time, and hopefully some time in the future, we'll realize it's better for everyone to use the same units, and have a referendum.


> It is interesting that it would be trivial for them to localize the units, it seems like they specifically didn't.

In addition to a possible esthetic preference for km, I had two thoughts for gameplay reasons why they wouldn't localize the units:

- Conversion to miles would have a loss of precision in the UI (2.0km vs 1.24m) - The name of the item is a 2.0km, 5.0km, 10km egg; it would seem odd when players were discussing the game online to refer to the items differently depending what country they are from.


>gameplay reasons why they wouldn't localize the units

Their previous game, Ingress, didn't have any gameplay reasons for using one unit system, yet it still used only metric.

See a four year old discussion about Ingress using the metric system alone here: https://reddit.com/r/Ingress/comments/13vjcw/the_real_nianti...


There are reasons. It's a worldwide game. Badges, that impact leveling mind you -- I got to level 16 on the back of an onyx Trekker badge, are awarded for walking 10, 100, 300, 1000, and 2500 km. The badges need to be consistent worldwide across all locales, because any player can play anywhere on the globe. It's exactly the same problem with the badge requirements as with the Pokemon egg distances. If you convert it, now the requirements don't make any sense. Hitting 2,500 km walked is a big nice round number, and gives you an onyx badge. Hitting 1,553.4 miles walked is meaningless, but that's what the top badge would be awarded for if written out in miles.


There were initially no badges, the game existed for about a year without them.


The game was in beta and running on a small budget at that point. Core gameplay features were a higher priority than localizing units for an audience of nerds that understand SI just fine anyway. And they probably had badges in mind for awhile before they actually released them, so they likely knew of the issues that localizing units would've had.


I think that partly explains why non-American airlines use miles over kilometers for frequent flyer rewards program.

A program denominated in kilometers would have to undergo conversion to miles if being deposited into a US account holder. On top of that, benefit levels would be different--a Star Alliance Gold level will be 50,000mi or 80467.2km.

However, ANA Mileage Club has a better ring to it than ANA Kilometerage Club.

Interestingly, most airlines are now moving away from miles in rewards programs and moving into the Unit of Measurement that counts the most: revenue.


In aviation, nautical miles are used (1.892 km). What is used for rewards programs?


The same, usually along a great circle route, and a multiplier based on your fare bucket.


That or a better marketing name.


> It is interesting that it would be trivial for them to localize the units, it seems like they specifically didn't

So, just like a good number of apps made by Americans for use in other countries.


Incidentally, why doesn't Android provide a global units setting?

Some apps that do change seem to do so based on location, but I don't often want to see miles and feet when I'm travelling in the USA. I assume most Americans travelling elsewhere would rather be given directions in miles.


In general I think software engineers do a bad job with units. We shouldn't work with floating point numbers, we should work with a number class that has a value and a unit.

Prior to working on Android & iOS I basically didn't bother with i18n. Now I never hardcode a string, it's always a reference to a string resource that is easily translated. I think this is a mindset shift brought about because the tools & libraries make it easy. The same is true for datetime formatting and unicode. We're collectively much better at supporting i18n in those areas than we were 15 years ago. I think the next step is for us to do the same but with numbers.


> we should work with a number class that has a value and a unit.

Not even a unit. I've always wanted a (majorly-adopted) language and platform where "Integer" or even "Number" are low-level mostly-ignored value types, and you instead work with a type that might be called (something snappier, but equivalent to) "RationalComplexPolynomialUnitedMeasurementWithPrecision".

Like, why can't my stdlib functions all take:

    (-5/6±3.5 + i±1/2) km^2/s^2
...and do something sensible (stoichiometrically) with it?


Because it gets messy very soon. To start with, you would have to pick a set of distributions that is closed under the set of operations you want to perform.

If you pick 'all normal distributions' as your set, that means that you can only allow addition, subtraction, and multiplication by a constant (= a normal distribution with zero variance); you won't be able to compute x^2, take a square root, compute |x|, etc. That rules out, for example, computing the variance of a set of inexactly known numbers.

To make matters worse, to do this really well, you have to track where values come from. You really want:

  x = 6±3.5m
  z = x - x
to have z equal to 0±0m, but

  x = 6±3.5m
  y = 6±3.5m
  z = x - y
to have z equal to 0±4.9m. Similarly, x+x should be 12±7m, and x+y should be 12±4.9m

The best you probably can do is to forget about the second issue, and do interval arithmetic. That is useful, but gives you extremely pessimistic results.

Edit: a good solution also would resolve the question of how to handle conditionals. if x > 0 could pick each of its branches according to the probability that x is larger than zero, or even execute both branches partially (whatever that would mean), according to the distribution of x.


Why would x+y be 12+-4.9m? shouldn't it be the same +-7m?


The parent is taking the error numbers as something like 1 standard deviation on a normal distribution, rather than an absolute limit. so, x = 6±3.5m means something like "x is equal to 6 + a random number taken from a normal distribution with standard deviation 3.5 centered around 0" and y is the same, but with a _different_ random number.

(I'm a little hazy on exactly what distribution is being assumed, but the basic idea of x and y being different random numbers is the important thing)

In principle one could also interpret x = 6±3.5m as "x is equal to 6 + a random number taken uniformly from the rand -3.5 to 3.5" or something, and then x+y would be 12+-7, but the real world numbers this is nominally supposed to represent don't really work that way. I think this is what is mean by "The best you probably can do is to forget about the second issue, and do interval arithmetic. That is useful, but gives you extremely pessimistic results."


Yea interval arithmatic is what i thought was being talked about before. It's one of the things that lead me to seeing all kinds of issues trying to move forward with the language i made/mentioned in another comment. I decided that I needed to lift how I was handling numerics into multiple types: floats, rationals, intervals, etc. and design the whole thing so that you could have more than one kind of interval (i hadn't thought about doing it the way you describe), like open and closed around the upper and lower limits.


Closest I can come is my esoteric language I made. It's a rough clone of Frink, but diverged during development in a number of ways:

http://search.cpan.org/dist/Language-Farnsworth/lib/Language...

It's missing the ranged/bracketed number support, but will do the rest of that.

13:27:11 < simcop2387> farnsworth: (-5/6+3.5 + i-1/2) km^2/s^2 -> "kJ/kg" 13:27:12 < farnsworth> simcop2387: (2166.66666666666 + 1000.00000000000*I) kJ/kg

It'll auto-convert things into floats if you use them, but it's 100 digit accuracy (configurable). Development has halted, mostly because I couldn't decide how I wanted to tackle adding objects as a first class data type and had a number of issues with the parser I needed to solve to make my life saner (easy way to force a difference between a variable and unit named "kg" etc.)

I might pick it up again and try using the parser combinators in Rust and actually compile the language down instead of an interpreter (though i'd remove eval[] to do that).


Some languages, like Haskell, let you extend the numerical types to whatever representation works well for your causes. A few years ago I wrote a library for embedding units of measure into every figure (at the type level), including e.g. auto-converting between units.

It's somewhat bitrotten but it may still be interesting if you're into this sort of thing: See [1] for an example of how it looks in practice.

[1] https://github.com/haasn/units/blob/master/tests/Tests.hs


   using SIUnits, SIUnits.ShortUnits
   using Measurements

   ((-5/6±0.1) + 1im)km^2/s^2

   > -833333.3333333334 ± 100000.0 + 1.0e6 ± 0.0im m²s⁻²

   typeof(((-5/6±0.1) + 1im)km^2/s^2)

   > SIUnits.SIQuantity{Complex{Measurements.Measurement{Float64}},2,0,-2,0,0,0,0,0,0}
In Julia.


All measurements in TeX must have a unit, even if the value is zero. Only counters take unitless numbers.


If the 150 years of attempting to metricate the UK is anything to go by, it'll happen by legislation otherwise barely at all outside of industry. The UK had legislation permitting metric units since the mid 1800s (as did the US apparently). Full metrication was recommended around a similar time!

It was 1965 legislation was passed to fully metricate within 10 years. We taught only metric in schools since the early 70s. A huge publicity campaign and changeover began. Only the EU really pushed it along by requiring only metric measurements, since around 2000, on packaging with a few exceptions. The previous 30 years was a weird half hearted mix of units mainly down to where something came from. So now we buy a 454g jar of jam etc. There's no need for it to be 1lb, but it almost always still is. You'll still hear folks young enough that even their parents were only taught metric ask for half a pound of something at the supermarket counter. The shop then gives them a metric marked equivalent.

Youngsters still talk of weight in pounds, and height in feet and so forth but have never been taught imperial units. A good part of must be social (hearing on tv, from parents etc), but I suspect the human friendliness of imperial units, being generally coarser (6ft or 182cm, 454g or 1lb) and often derived from body parts, is part of the reason they still stick around so tenaciously.

The thing outside EU weights and measures, weed, is also still always in ounces and quarters! :)


Probably nothing to do with the parents, do not underestimate the power of American TV


I thought it was common to quote weight in stone in the UK?


I was thinking of 5lb of potatoes, 1/2 lb of cheese when I was typing.

Yes body weight is usually stone and fractions, or stone and pounds. I expect everyone over 15 knows their weight in stone. I doubt most of them know how many pounds in a stone any more! :)


We've already seen metric creep in a little bit: I'd imagine pretty much every American out there can conceptualize what 2 liters looks like.

edit: in addition, military servicemembers should all have a good practical feel for 1km (one "klick").


Why is that? I'm just curious, because I (finnish) can't associate two liters with anything of the top of my head. Everything is always one liter.


The largest container of most soda brands available in American supermarkets is a 2L bottle.


The "family size" (or store size) soft drink bottles in Europe are usually 2L. Alternatively you can visualize 4 cans of energy drinks (bar the tiny redbull ones) or 4 small bottles of coke, or slightly more than 4 pints of beer ;)

I'm actually wondering what is 1L? The only thing I can think off is either the medium milk bottles or the "meal size" soft drink bottles that some convenience stores stock. Unless Finland has a very different bottling system than even Sweden I think you need to think again.


The 2L soft drinks are probably available, but I just never buy any of them. Milk, juice and yoghurt come in one liter packages.


From what I remember from most scandi supermarkets carton milks are 1 and 1.5L and plastic bottles are 2 and 2.5.

As far as soft drinks go bottles like these http://www.premierexports.co.uk/1595-2155-thickbox/diet-coke... are as far as I know standard across all of Europe and they are 2 liters.


I just went to my local S-Market and looked around a bit. The big soft drink bottles were all 1.5L (as noinsight said). Milk is available in 1.5L cartons too, but no plastic bottles of any kind. Of course, I do live in a pretty remote corner of the country, so maybe the selection isn't what it is in Helsinki.


Right, but I'd imagine you can conceptualize the 2l bottle of coke that you see in the supermarket - even if you don't buy it/drink it.


Sure, now that people mentioned them. That's why I said "can't associate .... of the top of my head". But that's not the point. The parent implied that there is something that's 2 liters that all Americans know, and I was curious as to what that is, because I, despite living in a metric country, couldn't think of anything.


It's far simpler for an American because soda in the US is widely available in three sizes:

* 12 fl oz (355 mL) aluminum can

* 20 fl oz (591 mL) plastic bottle

* 2L plastic bottle

Depending on the brand and store availability I've also seen 12 fl oz glass bottles, 1L bottles, and sometimes smaller sized cans as pretty standard sizes. Other types of drinks (such as energy drinks) can vary in what containers they use.

In general, though, if you're buying soda for a family or for more than one drink/meal, you're going to be buying a 2L bottle (and refer to it as such).


Do metric countries sell as many 2L soda bottles as the US does, relative to other soda sizes?


Actually, the soda bottles in Finland are 1,5 L at most.


2L soda bottles are ubiquitous.


Coincidentally, not in Finland. The largest soda bottles are 1,5 L.


We've been at this since the 70's.

Honestly the problem is we needed to keep tooling for manufacturing (eg, Detroit).


Detroit is mostly metric. Many US-built cars use all metric fasteners. For export, you have to use metric fasteners, because few outside the US have inch-sized tools. Imported cars are, of course, all metric. Aviation is mostly metric for the same reason. DoD is metric to be compatible with NATO.

Housing, however, hasn't converted at all. Building dimensions, HVAC and plumbing in the US are still on inch units.


...few outside the US have inch-sized tools.

An interesting frustration I've found in working with an immigrant friend: even though most of the fasteners we're turning are "imperial", he simply can't use imperial wrenches, because they require a familiarity with fractions. I'm fine with moving from half-inch to nine-sixteenths when the wrench is a bit too tight to fit, and frankly at this point I can usually tell the difference by eye before even opening the toolbox. OTOH my friend just goes from 13mm to 14mm to 15mm, ruining nuts and bolt-heads in the process.

Since tools should work for people rather than the other way around, one must conclude that metric-sized fasteners are superior to imperial-sized ones. It does seem odd that imperial fasteners were never sized by e.g. the twentieth of an inch, since that would have solved this problem completely.


Which is sad because the original complaint was they didn't want to switch because they'd need to replace their imperial tools. Joke's now on whoever said that, because it worked: now they need two sets of tools.


The humble 2x4 piece of lumber will likely be the last major industrial component to change over in the US.

Which actually measures 1-1/2" by 3-1/2", but let's not go there...


But will it?

In the UK 2x4, 2x2 etc is still commonly available, but it's 50x100mm. Probably has been for 30 years but only sold as 50x100 for ten or less. Metricating timber was easy because no one's going to notice or care if they get 25mm instead of each inch.

Metals, fastenings, pipes etc converted much slower because metric was often incompatible sizes without adapters.

> Which actually measures 1-1/2" by 3-1/2",

Isn't that because it's 2x4 before planing. cut lumber would be actually 2x4.


> Isn't that because it's 2x4 before planing. cut lumber would be actually 2x4.

It used to be, but now we're more efficient in our rough cutting and a 2x4 you buy was never actually a full 2x4.


And cut lengths of timber and sheet materials are usually multiples of 30cm but many people will order "8 foot" rather than 2.4m. Likewise joist and stud centres. However you can also get 3m or 5m, for example. Of course, most houses in the UK were built pre-metric system, so rooms will mostly be sized in feet, if they are in round units at all.


That actually raises an interesting question, what are dimensional lumber measurements like in metric?

Or do countries that use the SI system generally not use wood for framing?


In Canada we still use imperial for construction stuff, I guess for import/export reasons.

Oh and Farenheit for water and cooking temperatures. No idea why because I have no freaking idea what a Farenheit is otherwise.


And even then, it can vary by +/- 1/8". (I don't know if this is due to shrinkage from drying, or if they are deliberately milling it smaller to get more linear feet.)


More than that. It's 2x4 when cut wet, but shrinks to 1-1/2 x 3-1/2 when dry(er). Note that it will continue to grow and shrink over its life as humidity changes.

I don't try to figure out their fake dimensions; I just measure and buy what fits.

Oh, and this is why composites like MDF and plywood are better sometimes.


In reverse, in Europe measuring pipes ( or tools for them) diameter in inches is quite normal and ubiquitous. In oil business a lot of stuff is also measured in imperial units.

Let's not forget the monitor screen sizes. You can only get it in inches, so pretty every IT guy has a rough idea of how much is 14" and so on.


Yeah, the monitor one is a farce when you don't know aspect ratio though. And at some point the arguments over resolution start and then it gets truly awful. Monitors have scared me.


Except France, where even monitors and TVs are measured in cm.


At least Detroit seems to be solving itself. No more excuses soon, US!


> It is interesting that it would be trivial for them to localize the units, it seems like they specifically didn't.

I don't know if I'd call it "trivial". It's not a difficult and challenging problem, but it's boring and tends to be a pain in the butt because somebody has to hunt down everywhere numbers with units are displayed, and it's easy to miss some because it's not easy to notice at a glance whether a number is in metric or imperial, etc.. Even NASA has had problems with unit conversion.

And the conversion in software is easy, but it raises questions of how the converted units would affect gameplay. Would "Walk for 2 km" directly become "Walk for 1.24 miles". Or should everything change a bit so it becomes "Walk for 1 mile," so the numbers work out better.

At the end of the day, Americans aren't completely stupid. Kilometers aren't completely unheard of. They'll convert and get over it. Nobody's going to stop playing the game over it, so there's no point spending money to do the conversion and work out the issues around it.


Actually, it's super-easy to tell whether a number is metric or Imperial: it's metric. UK programmers aren't stupid.

Metric vs US Customary is a completely different matter and I couldn't possibly comment.


> hopefully some time in the future, we'll realize it's better for everyone to use the same units, and have a referendum.

Imperialeave!


Menter!


It's been slowly seeping in since at least the 70s, when the Metric Conversion Act was passed. I remember when I was a little kid in Michigan all the street signage had both kilometers and miles on them.

Yet here we are over 40 years later and the penetration of metric is still basically nil (in day to day scenarios, not science/engineering). I'm not convinced America will switch to metric in my life time.


Please don't let's have a referendum - the entire planet will go back to imperial - in the UK at least there's still a huge, possibly majority, definitely passionate, group that prefer imperial units. Hence we still have one foot in mph and pints.

There's talk of it happening regardless, as without the EU there's no requirement here to use SI units - and one pundit even suggested a return to pre-decimal currency.

Either way, people tend to value tradition more than progress or rationalisation. Having a system of weights based on the weight of a grain of emmer wheat is preferable to plenty of people, who don't have to write code or multiply weights or do science, and just want familiar human-scale units. Hell, I'm sure plenty of the aforementioned would prefer imperial too, for the same reason.


> There's talk of it happening regardless, as without the EU there's no requirement here to use SI units

The EU did initially have the goal of getting rid of all non-metric units, but gave up in early 2000s since the UK was opposed.

A part of me could see an UK-in-the-EEA being forced to switch to metric, if the EU were to go full metric (with the UK not having a vote of course), and that's applying to the EEA (incl UK). And if the UK were to apply to rejoin the EU, I suspect metricification would be one of the requirements of reentry.

So the brexit vote might increase the chance of the UK going metric. :)


> Either way, people tend to value tradition more than progress or rationalisation.

Don't get me wrong, I'm pro-metric, but the old units are not entirely irrational.

For instance, there are 12 inches in a foot, which may seem odd, unless you need to measure 1/3 of a foot. You might argue that the foot represents a future society that uses base-12, while metric lags behind, in the not-as-divisible base-10 world.

It's also interesting to note that on rulers, in the US anyway, each inch is subdivided into 16 sub-units, so measurements are usually given as, say, 3 3/16 inches rather than 3.1875 or (rounding) 3.2 inches. In other words, hexadecimal rather than decimal.


So, 12 inches in a foot isn't odd because it makes it easier to measure a third of a foot, but, apparently, people need one eighth or one sixteenth of an inch way more often than one third, so the rational thing to do is to divide an inch in 16 parts, not 12?

Also, people rarely need a third of a mile, so why bother giving that a name or even making that an integral number of yards? But hey, if you happen to need one eleventh of a mile, rejoice: that's 160 yards, and one eighth of a mile, apparently, is used so much that it has its own name.

Correlation is not causation, but chances are a third of a foot is more popular because there are 12 inches in a foot, not the other way around.


Imperial units would be a lot more defensible if they were consistent. But just in your example we've got things being divided into 12 and 16 parts, and many other random divisors are common. I'd be onboard with a system of units where the divisor is always constant, but having it random is annoying. Fortunately there is a system of units where the divisor is always constant - SI! Yeah, it's 10 instead of 12, but it'll have to do.


I agree that the Imperial system is a mess. 5,280 feet in a mile?

But my point is that people who prefer old units are not being entirely irrational, or averse to change.

It's just that for their particular use case (making human-scale furniture out of wood, for example), the Imperial system works pretty well, and perhaps better than the base-10 metric system.

If they had to spend their days converting between acres and square feet (43,560 of the latter go into the former, by the way), they might be more inclined to switch to metric.


One thousand paces in a mile, where each pace is two steps.

A property of the US customary units is they tend to be more optimized for specific uses at a given scales, with little thought given to changing scales. Metric units make conversion easier, at the cost of often less suitable for use at scale - how many steps does it take to go a kilometer?


Unless you're in a military unit that is on the march, what does the number of steps in a kilometer matter for at all? And there is a huge natural variation in human stride length anyway -- you won't be surprised to know that the figure you mentioned for miles is an average that only applies for adult males of military height (i.e. not even shorter men). I think SI units are great for measuring distance at scale. Nanometers, micrometers, millimeters, centimeters, meters, and kilometers are all in common usage, and can represent pretty much anything you'd need. By contrast, it's imperial that has the real problems with use at scale, specifically down at tiny scales.


> adult males of military height (i.e. not even shorter men)

Adult males of roman military height, so probably about 5'7" (170cm): http://history.stackexchange.com/questions/17072/average-hei...


> Unless you're in a military unit that is on the march, what does the number of steps in a kilometer matter for at all?

Playing Pokemon Go?


I do play Pokemon Go, and I don't see what the number of steps has to do with anything. Nothing in the game is step-based; it's all kilometer based.


A mile is no longer anything resembling 1000 paces, given that a standard imperial pace is 5 feet, rather than 5'3" and some change.

Besides, it takes about 10 minutes of walking to go a kilometer. You don't count paces, do you?


> in the UK at least there's still a huge, possibly majority, definitely passionate, group that prefer imperial units.

Erm... no. Anyone over 60, probably, but young people here don't even have any idea what a pound or ounce is.


It's slightly more confusing for young people over here -- we mostly deal in metric, but we still do have pints of beer (from the tap -- the bottles are 330 or 500 ml), miles, and we measure ourselves in feet, inches, and stone (although you do run in to people who use cm & kg, so that varies a bit)


Not only that, but draught beer and cider have to be sold in pints (or 1/3, 1/2 or 2/3) while nothing else is allowed to be, so a "pint" of coke is supposed to actually be 500ml, and spirits are in multiples of 25ml or 35ml.


Also its a buggy mess, I dont think distance localisation would be that much of a priority if they also couldnt build something that doesnt hang every few minutes. I've been working specifically as a Unity developer for a couple of years and this thing smacks of amateurishness.


But why woukd Americans care if the entire world uses the same units of weight and distance?


Why would the world care if Americans are using a different unit?


Why, indeed. My impression is that you are European. Do you care which system(s) we use, and if so, why?


I don't care which systems you use, unless I have to write an app that works everywhere, in which case I have to make it work one way for the whole world and another for the US and Liberia.


First, TFA illustrates that this isn't really a requirement, at least for some apps. Second, L11n for different locales is an unavoidable aspect of app production. If it's difficult to use measures that are intelligible to users, it's probably difficult to make their lives better in other ways too.

This seems different than the sky-is-falling metric appeals we see from time to time.


"Requirement" is relative. People will definitely prefer their own units to others.

Localization has to be done, sure. That doesn't mean it's binary, that you either localize or you don't. The more things you have to localize, the more effort it is, and that's why standards are good.

I don't agree with "if it's hard for you to spend time on things that aren't necessary, it will be hard to spend time on things that are necessary, too". I think it's objective that the fewer changes you have to do because of arbitrary legacy, the better it is.

It would be easier to reach everyone if we all spoke the same language, had the same culture, used the same units, etc. It's hard to teach everyone the same language, but it's less hard to agree on a system of units. Almost everyone else has done it.


Urgh, more discussions involving some contrived correspondence between 1 inch and 0.01m, 1 foot and 1m, and 1 mile and 1000m. There is only the metre; divide it up however you like, compare it to whatever imperial units you like, but "centi", "kilo", etc. are just a different way of writing ÷100 and x1000.

The "real" reason to use metric is that all of the constants of proportionality are defined as 1. "1m = 100cm" is trivially true, by the definition of "centi", but 1m is also equal to all of the following, which I wouldn't even want to attempt to figure out in imperial units:

    1 metre

    1 Joule / 1 Newton  -- Applying 1N of force over a 1m distance requires 1J of energy

    1 Volt * 1 Coulomb / 1 Newton  -- 1 Volt is a potential difference of 1 Joule per Coulomb of charge

    1 Volt * (1 Amp / 1 second) / 1 Newton  -- 1 Amp of current is 1 Coulomb per second

    1 Volt * 1 Amp / 1 Newton * 1 second  -- (by rearranging)

    1 Watt / 1 second * 1 Newton  -- 1 Volt * 1 Amp gives 1 Watt of power

    1 Watt / 1 second * 1 kilogram * (1 metre / (1 second * 1 second))  -- From Newton, force is mass * acceleration

    1 Watt / (1 kilogram * 1 metre / 1 second)  -- (by rearranging)

    1 Watt * 1 second / 1 kilogram * 1 metre  -- (by rearranging)

    (1 Joule / 1 second) * 1 second / 1 kilogram * 1 metre  -- 1 Watt is 1 Joule per second
And so on. We just need to get rid of anachronisms like litres (1l = 0.001m^3), defining "kilogram" as the name of a unit, and of course prevent the use of weird language-juggling like reporting the distance to Saturn as "1000 million kilometres", or measuring energy in "kilowatt hours".

Genuine question: does the imperial system even have distinct units for mass and force? I tend to see ounces, pounds, stones, etc. converted to kilograms, which implies they measure mass; but pressure seems to be measured in pounds per square inch, which would be a 2D density (e.g. used as a measure of paper quality).


> Genuine question: does the imperial system even have distinct units for mass and force?

The slug is the unambiguous unit of mass in the imperial system. It is rarely heard of, and not fun to use.

https://en.wikipedia.org/wiki/Slug_(mass)


Yes. The pound is a measure of force and the slug is a measure of mass (1 lb = 1 slug*ft/s^2). That said, a the pound-mass (lbf for pound-force, lbm for pound-mass) is probably used more in casual conversation because it has surface gravity built it.


For electrical systems, kWh (and Ah) are usually more useful units than joules (resp. coulombs), but recent tendency of quoting power in units like "kWh per hour" is really absurd.


If we just needed these quantities as the inputs to an equation, sure, we should express them as 1E12 meters or (whatever x 3.6E6) Joules. But it turns out units are not only used for computing, but for communication. I am familiar with the kilometer because I know what it feels like to walk one. I am exposed to watts because I have grown up using 60W lightbulbs. Now, you could call this history and experience needless in the context of science. But in the context of my comprehension of the results of science, they are important, however "weird" they are to compute. I would much prefer for my computer to multiply by an extra conversion factor than to re-calibrate my mind to use "more efficient" units.


> If we just needed these quantities as the inputs to an equation, sure, we should express them as 1E12 meters or (whatever x 3.6E6) Joules.

To be clear, I wasn't advocating against the use of km, cm, kW, etc.; only against the common contrivance that "the cm", "the km", etc. are some sort of independent units with remarkable power-of-ten conversion rules.

As an analogy, it's like claiming that the number ½ ("one half") is, coincidentally, the same as the result of "1 ÷ 2" ("one divided by two"). In fact, there is no coincidence; the 'claim' is just describing the intended meaning of the "x over y" notation. Likewise, powers-of-ten are the intended meaning of the "kilo", "centi", etc. notation.

In other words, expressing quantities in kilometres is expressing them in metres; there's no need to use, say, scientific notation to make it "more metric".

My point about "1000 million kilometres" was simply that it's overly complicated (3 different factors, written in 3 different ways: one with digits, one in English and one as a prefix); why not "1 billion kilometres", "1 trillion metres" or even "1 terametre" ;)

The problem with kilowatthours isn't the "kilo" or the "Watt", but the "hours"; it introduces an unnecessary factor of 3600 compared to other units. For example, a megawattsecond (AKA a megajoule) has the same order of magnitude (1kWh = 3.6 MWs)


> Unfortunately, there’s no way to change the in-game units in Pokémon Go.

i think they meant 'fortunately'


Finally, a way to teach Americans the metric system that doesn't involve weed


Or landing on Mars.


I switched to using primarily Celsius a year or two ago. It's been tremendously useful for me, moreso than switching to metres (which I've been doing as well, though not as aggressively). Like most tech companies we have to frequently interact internationally, and everyone uses metric outside of the U.S. Knowing Celsius has made even basic conversations easier. I mean, "How's the weather where you are?" is such a common conversation starter, and it's one I can actually meaningfully have with people outside the U.S. now. No more "oh, pretty hot", instead I can just say "It's over 35 here!"

And as an engineer I obviously need to deal with metric for most everything (except those damned PCBs; thou, really!?), so it's very useful to have an intuitive understanding of what temperature my chip is at, or how thick 3mm is without grabbing a ruler.

Switching to Celsius is also a lot easier than switching to metres. You can get through a day using only Celsius, but you'll have a lot of trouble traveling around in a car using metres.


If it is of any consolation for you, metric is becoming increasingly common in PCB design. New ICs packages are all metric and even the traditional resistors are being measured in metric (damned be the 0603).


When I read the title of this post, I first imagined a happy and earnest grade-school teacher saying it, perhaps sharing the story with some fellow teachers in a teacher's lounge, all discussing it positively.

Then I imagined an angry state legislator slamming his or her hand down on a brown lacquered table in some indiscriminate political conference room and yelling, "Pokémon Go Is Teaching Americans the Metric System!" and a bunch of interns scurrying in fright.


Metric is in a lot more places than you'd care to believe. And it's been there for decades.

Ask any high school student if their science classes are in metric units or English units.

What units does the AP Physics test use? How about the SAT? And college chemistry 101?


I still think the ,/. decimal separator issue is bigger deal.


It's also teaching Americans to go ride bikes again, or it will be eventually. I say this because I currently have 35km worth of eggs "stacked up" beyond the 2 that I'm gradually working on, and I'm sure that I'll accumulate more before I manage to get rid of all of those.

On the upside, it's provided some gamification to the increased walking that I was starting to do anyway, but it's also making me think about getting my bike down from the garage ceiling where it's been hanging for a couple years. Perhaps I'll start riding for quick trips out instead of driving......


someone at work tried to hatch their kids eggs during the bike rides to work and said biking was too fast for it to work...


I heard something about you have to go less than 24 km/h. During a leisure bike ride, I at least managed to hatch some eggs and get the tracker to count the distance.

A safety tip is just to open the app and then put it in your pocket with the touchscreen facing outwards. If inwards the heat and sweat from your thigh can actually interact with the screen.


If you're going to do this, also turn on power saver option, and put it in your pocket top-down - that mostly turns off the screen and should save quite a bit of power on AMOLED screens, though maybe not so much on LCD.


It isn't talked about much, but riding a bicycle is actually really dangerous. I say that as someone who loves riding and has done quite a bit of it through my years. It's the most dangerous mode of transportation between driving, biking, and walking. That's based on my rough estimations of micromorts/hour from https://en.wikipedia.org/wiki/Micromort; 0.26 micromorts/hr, 1.25 micromorts/hr, and 0.18 micromorts/hr respectively. That makes walking the safest by a good margin, and biking is almost 5 times more dangerous than driving. In fact, biking just 80 miles is roughly equivalent to one hang gliding or skydiving session.

I don't really want to dissuade people from riding bikes; it can be a lot of fun and healthy. But it's quite dangerous, and I gave up riding a few years ago because of that and because everyone on the road hates you; cars, cops, and peds alike. They all pretty much want you dead. (I've ridden mostly suburbs, both in bike friendly cities and not)


Even more dangerous if your attention is on the phone mounted on the handlebars running Pokemon, as I saw on the weekend.


But what about the health benefits of cycling? Would that cancel it out?


Given the obesity epidemic, it would actually be reasonable to let Americans walk 1.6 times as far.


Americans know the metric system. They just don't use it regularly for things outside science and technology. Everyone has to learn it though.


Anyone interested in running has known how many miles are in 5km for a long time.


I don't know much of the imperial system, but since the metric system only has one unit of length (the metre) it would presumably be easiest to convert that directly into imperial, rather than choosing arbitrary multiples (e.g. 1000m).

In fact, the metre coincides quite nicely with 1 yard (or 1.1 yards if you want more precision; which is still "just ones"). That seems much easier to remember than, say, 1610 metres/mile, or 0.62 miles/1000m.

Once you're in imperial you can presumably use the various conversion rules to get feet, miles, inches, furlongs, etc.


I grew up with a mix of metric and imperial (like most people in the UK), but the imperial conversions are all really weird and hard to remember -- 1760 yards to the mile?? For me it's easier to remember "a yard is a little less than a meter" and "a mile is about 1⅔ km", and then use the most natural metric unit for figuring out estimates.


More importantly people, Americans are now walking 5km...maybe there will be a small dip in obesity rate while the all is trending.


It's unlikely. Unless you carefully control your eating more exercise leads to weight gain, not loss.

Exercise is great for general health, but it's useless for weight loss unless you are also on a carefully controlled diet. (i.e. if you exercise you will want to eat more. Unless you force yourself not to, you eat up gaining weight.)


Next thing you know we'll be buying soda in two-liter bottles and measuring our pills in milligrams.


I think the world would be a much better place if we compromised so that US moves to SI and rest of the world gets rid of the decimal comma and starts to use the decimal point.

And as an icing to the cake, everyone could switch to ISO 8601 date formatting everywhere.


This is how it's been in Australia for many decades. I guess the world truly is a better place here.


The Fibonacci sequence is a pretty good rule of thumb for converting between miles and kilometres. 2 miles is about 3km, 3 miles is 5km, 5 miles is 8km, etc.


So are drugs.


Lol why?


From what I understand, cocaine and other harder drugs are sold by the gram at an end-user level, and by the kilogram at the street distribution level.


Conversely you by weed in imperial units, pretty much everywhere - except Amsterdam, where you buy in 7g increments (28.3g in an Oz).


I'm not certain, but I'm pretty sure it's sold per gram in the UK.

The American units sound very unfamiliar to most British people under about 40 years old. 3/8 oz?

Road speed is still given in miles per hour, but anything where fractions or calculation might get involved (cooking, measuring furniture, drinking spirits) is done using metric units.


In the early noughties it was certainly in ounces, though it may have changed in the past decade.


In Northern Germany, it's definitely in grams. That much I know, considering half of my high school used to talk all day about that.


That used to be the case, but lately I learned the gram is becoming a common unit for weed - replacing the dime bag.

The eighth is still common, as in (1/8 of an ounce) but now measured as 3.5 grams.

It's a weird mix right now.


Well, 7g is about a quarter oz, so it's still imperial influenced at least.

And in the US, we often refer to imperial amounts by their gram amounts as well. Especially in legal states I feel. Usual amounts are 1 gram, 3.5, 7, 14 and so on, lining up with the old, small amount ("dime"), eighth, quarter, and half o.


In Germany, it's common to measure drugs of all kinds, including dope, in (kilo/milli) grams (kg if you're talking about some serious shit, mg for the synth stuff).


I think it's just in grams. You're "allowed" to carry 5 grams on you, so 7g wouldn't make sense.


As a counter point, buying marijuana as a teenager was the way I learned that there are 28 grams in an ounce and 16 ounces in a pound.


Those are measured in grams and kilos

Source: movies & TV. I have 0 experience with drugs.


Finally!


Shopping for groceries outside of the U.S. is so straight-forward, the U.S. food industry should worry about loss of profits in moving to metric.

Imperial:

$4.49 / lb

0.67 lbs

≈ ???

Metric:

$9.89 / kg

$0.3 kg

≈ $3.00


This example doesn't very well, it's rather awkwardly contrived. In the US you would just buy 1/2 or 3/4 of a pound, not 1/3.

Similarly, I wouldn't expect you to buy 0.67 kg of food priced by weight outside of the US.


Whatever point you're trying to make is beyond me. Why is multiplying by 0.3 easier than multiplying by 2/3?


Yeah, my comment didn't make sense. Terrible example. Was running out the door.

I meant to say that in the U.S. things are marked in ounces. So, it's like calculating (10 oz / 16 oz.) * price. Whereas, elsewhere it's usually 100 grams.


No it's not. People just ask Google or Siri. They still don't know that 1km equals 0.62 miles.


Sure, but once you do that for the 4th or 5th time you'll remember that it's "sorta close to half a mile".


No it isn't. At most it is teaching a single unit, not the system. And if all it's doing is teaching them how to convert that unit into something they know, rather than them actually use the kilometer for what it is, then it teaches nothing.

Until you live with americans you don't appreciate how focused they are on accent and vocabulary. Social groups are defined by their vocab. Someone using the wrong synonym for the context betrays their foreignness. I remember once using the phrase "by whatever metric" in a lecture only to be informed that he correct wording was "by whatever measurement". Even the word is a red flag. The was a law lecture. Had it been a physics lecture my choice would have been apt. It isn't a lack of knowledge that holds them back. It's a class system in which the use of the metric system is an important identifier.

Also, pokemon can do nothing in comparison to the US military's increased use of metric, but even there its use in casual conversation remains an identifier of background/rank history.




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