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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

#91

Post by quietbritishjim »

f33d5173 wrote: post #72
quietbritishjim wrote: post #54

Earlier quoted context omitted.

Depending on what exactly your figures were/are, you might benefit from the viridis colour map, available in matplotlib and R (and probably in many other places). It's colourful, so those without colour blindness get a richer display than if you used greyscale, and the colours chosen aren't too affected by most common forms of colour blindness. But for those that really can't see the colours, even if you literally ju…

Am I wrong that in that article magma appears to do better? Particularly in the last two (red-blind and grayscale), it seems like viridis looks the same for large parts of the scale, while magma retains its distinction.

I think it just won the poll [1] because it subjectively looks nicer. NJS, in that video, said something like: I don't care which wins, they're all so much better than the current situation. But magma is a good choice too and it's also available in matplotlib.

[1] http://bids.github.io/colormap/

Re: Why Japan has blue traffic lights instead of green

#92

Post by NegativeK »

teruakohatu wrote: post #14
smolder wrote: post #10

Earlier quoted context omitted.

Yes. They can still drive fine, but don't get the benefits of color coding, like being able to infer whether red or green is lit from the light reflected off of other objects. That becomes somewhat important in low visibility situations where the position is hard to determine.

It seems the harder difficulty is red and yellow, see the comments in this article, but led lights have improved the situation for some: https://www.color-blindness.com/2007/02/06/colorblind-at-the...

There are a few different types of colorblindness, so I wouldn't extrapolate that.

For me personally, the green light looks much closer to a white than to, say, the green of a grass.

Re: Why Japan has blue traffic lights instead of green

#93

Post by NegativeK »

perilunar wrote: post #60
mathieuh wrote: post #5

Earlier quoted context omitted.

Traffic lights are still fine for colour-blind people aren't they? The order of the lights doesn't change.

With the switch from incandescent bulbs to LED traffic lights it would be very easy to change the shape of the lights: e.g. octagonal for stop, triangular for caution, and circular for go. Keep the colors, but add shape as well. Seems like an obvious and useful change to me.

That might fall apart for people with poor visual acuity.

Re: Why Japan has blue traffic lights instead of green

#94

Post by Findecanor »

cxrlosfx wrote: post #51

Red cabbage or Blue Cabagge, in northern Germany is also called red cabbage (Rotkohl), same color for some regions of Austria and Switzerland (Rotkraut). In southern Germany it is called Blue Cabagge (Blaukraut). If you ask people in Germany what the color of the vegetable is, they will answer "purple" (lila). There are some strange ways in the evolution of a language, depending on the region and events in the region…

Red cabbage is a bit of a weird example because its colour depends first on the acidity/basicity of the soil it was grown in, and then when you're using it on the acidity of other ingredients.

For example, if you cook it with apple (which is acidic), it will turn redder.

Re: Why Japan has blue traffic lights instead of green

#95

Post by vages »

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 am looking out my hotel room window in Hiroshima in this very instant, and I even got my wife to confirm it: The traffic lights definitely are GREEN.

Re: Why Japan has blue traffic lights instead of green

#96

Post by iopq »

the_mitsuhiko wrote: post #65
iopq wrote: post #56

Earlier quoted context omitted.

Because they use 绿, not 青 so it would not result in blue lights But in Korea they have the same confusion: https://www.dreamstime.com/traffic-lights-road-blue-speed-li...

To the best of my knowledge it's different in Korea. As far as I know the call it blue lights but they are green.

They are not blue, but because the word for blue is also ambiguous they are more like a teal color

Re: Why Japan has blue traffic lights instead of green

#97

Post by manxman »

troad wrote: post #50
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 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…

[flagged]

Re: Why Japan has blue traffic lights instead of green

#98

Post by mcpackieh »

troad wrote: post #50
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 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…

In English, things that are orange are often called red. Particularly, but not limited to, hair.

Re: Why Japan has blue traffic lights instead of green

#99

Post by kouru225 »

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…

My memory form my time living in Japan is that they do not have a consistent shade of blue/green that their traffic lights conform to. You will see completely different colors depending on the location, and even see different colors within the same location. Some areas are more blue and some areas are more green.

Re: Why Japan has blue traffic lights instead of green

#100

Post by blincoln »

NegativeK wrote: post #93
perilunar wrote: post #60

Earlier quoted context omitted.

With the switch from incandescent bulbs to LED traffic lights it would be very easy to change the shape of the lights: e.g. octagonal for stop, triangular for caution, and circular for go. Keep the colors, but add shape as well. Seems like an obvious and useful change to me.

That might fall apart for people with poor visual acuity.

If they're roughly the same size and in the same order as the round lights today, people with poor visual acuity would still see more or less what they see currently.
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