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Why Japan has blue traffic lights instead of green

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Re: Why Japan has blue traffic lights instead of green

#201

Post by pbhjpbhj »

kryptozinc wrote: post #122
2143 wrote: post #86

Just a data point that I want to put out there. I have long heard that Japan has blue traffic lights. Earlier this year I visited Japan. Because I had heard about the blue traffic light situation, I paid special attention to the traffic lights. They all appeared green to me. In both Tokyo and Osaka. Okay maybe a tinge of blue if you look at it and wonder 'is this blue?' , but the only reason I wondered was because I…

you would know if you read the article :)

From the Guidelines:

>Please don't comment on whether someone read an article.

Which you'd know if you read the guidelines (:

https://news.ycombinator.com/newsguidelines.html

Re: Why Japan has blue traffic lights instead of green

#202

Post by nagisa »

ensignavenger wrote: post #143
2143 wrote: post #86

Just a data point that I want to put out there. I have long heard that Japan has blue traffic lights. Earlier this year I visited Japan. Because I had heard about the blue traffic light situation, I paid special attention to the traffic lights. They all appeared green to me. In both Tokyo and Osaka. Okay maybe a tinge of blue if you look at it and wonder 'is this blue?' , but the only reason I wondered was because I…

I have been to Japan a couple of times. The first time I was there in 2016 many of the lights were very blue with hint of green. I noticed when I was there over the summer that the lights were getting greener, many of them pretty much just green. I think they have been transitioning, perhaps as they have updated to LED lights or something they have been making them more green?

I wouldn’t be surprised if it had something to do with the Tokyo olympics. Are other cities also green now?

Re: Why Japan has blue traffic lights instead of green

#203

Post by eric-hu »

NovemberWhiskey wrote: post #198
2143 wrote: post #86

Just a data point that I want to put out there. I have long heard that Japan has blue traffic lights. Earlier this year I visited Japan. Because I had heard about the blue traffic light situation, I paid special attention to the traffic lights. They all appeared green to me. In both Tokyo and Osaka. Okay maybe a tinge of blue if you look at it and wonder 'is this blue?' , but the only reason I wondered was because I…

The "go" signal in traffic lights in Japan is 青い (あおい) "aoi". That adjective in Japanese means both blue and green. The Japanese language didn't have a widely-adopted word for just "green" - 緑 (みどり) "midori" - until after WWII. Green apples or vegetables are still "aoi", for example. I lived in Japan for four years and never saw a blue traffic light.

Do you know more about the history of this color use? It’s surprising to me that midori uses the kanji for green in Chinese if it’s such a recent idea in Japan.

Re: Why Japan has blue traffic lights instead of green

#204

Post by ipsi »

Cockbrand wrote: post #181
chrisdsaldivar wrote: post #118

Earlier quoted context omitted.

Yes, on average women can perceive more colors than men [1] Anecdotally, in high school we all took this test for a class [2] and the girls did a lot better than us. Although some guys were able to score pretty well on it. I don’t remember if this was the exact test but it’s very similar. [1] https://pubmed.ncbi.nlm.nih.gov/21675035/ [2] https://www.xrite.com/hue-test

Like many siblings, I'm male and got a perfect score as well. I don't think that I have perfect vision, but I'd rather assume the test is flawed.

It's pretty clear that it's "Based on the Farnsworth Munsell 100 Hue Test," and "this is not a replacement for the full test!" I think if you did particularly poorly on the online test then it's worth looking at whether you need to do the full test, as you might have colour blindness (or a terrible monitor). But a perfect score isn't super-meaningful.

Re: Why Japan has blue traffic lights instead of green

#205

Post by arp242 »

jrockway wrote: post #197
arp242 wrote: post #165

Earlier quoted context omitted.

Please report the exact wavelength for verification.

Colors are not necessarily a single wavelength, and the human visual system can't distinguish between identical "tristimulus" caused by a single wavelength or a mixture of wavelengths. This is why color monitors with red, green, and blue pixels work. The red, green, and blue are designed to stimulate your long, medium, and short wavelength receptors. Models like CIE1931 map wavelengths to tristimulus values, which yo…

Stop ruining my jokes with facts!

Re: Why Japan has blue traffic lights instead of green

#206

Post by jacquesm »

ipsi wrote: post #204
Cockbrand wrote: post #181

Earlier quoted context omitted.

Like many siblings, I'm male and got a perfect score as well. I don't think that I have perfect vision, but I'd rather assume the test is flawed.

It's pretty clear that it's "Based on the Farnsworth Munsell 100 Hue Test," and "this is not a replacement for the full test!" I think if you did particularly poorly on the online test then it's worth looking at whether you need to do the full test, as you might have colour blindness (or a terrible monitor). But a perfect score isn't super-meaningful.

Looking at this test on my monitors I would bet it's the 'terrible monitor' before color blindness by a longshot, one shows pretty good color the other is entirely washed out.

Re: Why Japan has blue traffic lights instead of green

#207

Post by aaroninsf »

calfuris wrote: post #129
troad wrote: post #50

Earlier quoted context omitted.

I trained as a linguist and you hit the nail on the head. Word meanings are fuzzy clouds of references and nuances, and every language has slightly different clouds. There is nothing magical about this, despite the recurrent lizard-brain notion that words or names are somehow mystical and intrinsic, and that these differences must somehow be meaningful. Differences are quite common with colour terms - you don’t need…

Words do seem to have some influence on perception. Specifically, colors appear to be easier to distinguish if they fall within the bounds of separate basic color terms ( https://www.pnas.org/doi/10.1073/pnas.0701644104 ).

I would say appropriately enough this at this level it becomes an issue of semantics, and pragmatics, and specificity,

results like this AFAIK are real (have not been found irreproducible, or limited to e.g. Russian), but, what they demonstrate is best understood in the specific terms of their hypothesis and findings—the "risk" or possible alternative being, to extrapolate the "pernicious" lay belief into some strongish Sapir-Whorf "your reality/my reality."

I.e. measurably faster performance on discrimination tasks, does not map broadly to "perceives differently." Your phrasing was appropriately nuanced, "influences" is a reasonably lay summary...

...but "Japanese-as-first-language speakers perceive blue and green as differently as e.g. English speakers" is still definitely much more true than the alternative.

Personally I was sad to learn strong S-W didn't hold up. It is quite a captivating idea. So too this popular middle ground around color naming.

I find it quite interesting the way experiments like this are construed to try to tease apart linguistic, cognitive, and perceptual factors.

Re: Why Japan has blue traffic lights instead of green

#208

Post by jrockway »

yznlp wrote: post #29

Not a linguist. I feel like this is just an issue of imperfect correspondence between the word "blue" in English and "ao" in Japanese. The article explains the historical reason why ao encompasses both blue and green, so I think the concept of semantic field comes into play here. As an analogy, a MacBook is a type of laptop, and laptops, desktops and tablets are all IT devices (for lack of a better word). Apple might…

I think yellow and amber are a good example of similar confusion in English. According to the NYS driver's manual, traffic lights are yellow and marker lights on vehicles are amber. They both look yellow to me. Doing some research around the Internets, I see people insisting that governments always call traffic lights amber, but that's not true. Either way, nobody knows what "amber" means except people manufacturing lights and people that just looked it up because they're reading a comment about it. But, again, if you ask someone "is the middle traffic light amber?" they'd probably say yes, just like Japanese people will be happy to mark the green light as ao.

Re: Why Japan has blue traffic lights instead of green

#210

Post by jacquesm »

crazygringo wrote: post #194
dragonwriter wrote: post #153

Earlier quoted context omitted.

> Which really blows some people's minds. "Well it's a little bit orange." No it's not, not your regular American bottled or fresh OJ. Straight-up yellow. Well, it wouldn't be that weird if you were right because we name fruit juices after the fruit, not the juice color, but I’ve never seen orange juice that wasn't distinctly on the orange side of yellow, even if its more yellow than orange, including fresh and bottl…

You're just proving my point, of how people insist it's still somehow orange. Sure, almost nothing is perfectly a 60° hue of yellow. But the color orange is all the way at 30°. And if you look at the HSL values of the juice in product photos like the following, you'll get hue values of around 52°: https://www.amazon.com/Tropicana-Orange-Juice-No-Pulp/dp/B07... https://www.amazon.com/Simply-Orange-Pulp-Juice-Drink/dp/…

That's very interesting. We tend to use a lot of logic as a layer on top of our senses to tell us what we are looking at. One of the most interesting cases (which I can't find a reference for, so sorry) of this that I've come across was an accident in Amsterdam where the person whose car was involved in an accident swore that the other car in the accident had gone against traffic. But from the situation after the accident and eye witnesses it made no sense to believe this. But much later some security cam footage was submitted as evidence that showed the car that had gone against traffic somehow flipping into the position that showed them coming from the right and coming to a rest just like the final scene after the accident was. So, in spite of all defiance of logic the occupants of the first car had it right and the 'eye witnesses' and the accident investigators all had it wrong (and the occupants of the vehicle that caused the accident were lying and could probably not believe they were getting away with it).

I'm sure that in the larger fraction of all accidents eye witnesses will at least get the basics right and that parties are not going to lie about what actually happened. But it's interesting how two minutes after an accident with five witnesses there are probably 10 conflicting stories about 'how it happened' and it makes me wary of any eye witness testimony, especially in less than ideal conditions (night, rain, distance etc). When I first heard about the above case the explanation was that eye witnesses probably heard the crash, looked up and immediately created a mental reconstruction of what must have happened based on what they saw and then reported this as the fact rather than to simply say that they didn't see anything until the moment of impact.

I really should dig a bit more to see if I can turn up something about this case, it is very interesting given your comment because you have provided another example of what I think is the same thing.

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