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Boston public schools map switch aims to amend 500 years of distortion (theguardian.com)
19 points by kuon 216 days ago | hide | past | web | 19 comments | favorite



Ah yes, map projections. Time for everyone to complain about why the projection is inaccurate (because all of them are).

The problem with Gall-Peters is that it gives a misleading impression of equatorial regions--it scrunches up the width and exaggerates the height. Humans are bad at estimating area when the rectangles have different ratios for their sides--notice how Africa appears to be the same size as Asia; in reality, it's only ~⅔ the size.

So, yeah, the Mercator is horrible as a projection. Cartographers have known that for over a hundred years. Yet if you want a better map projection, there are several decent ones that are better than Gall-Peters (which is basically the inverse of the Mercator: exaggerate the equator at expense of the poles). Even if you limit yourself to equal-area, Mollweide and Eckert do better jobs of avoiding shape distortion. Outside of equal-area, well, Robinson and Winkel tripel tend to do very well, striking a decent balance between all of the different kinds of distortions.

As a general rule of thumb, any map projection that insists that it depict a globe as a rectangle seems to do very terribly.


Globes! I'm sure I had a globe in my classroom in grade school and I had one on my desk at home. I'm sure they didn't represent the actual shape of the earth, but much better in terms of visualization.


Even if your globe is a perfect sphere, it's good enough for all practical purposes. The difference between the Earth's diameter across the equator vs. between the north and south poles is only 3.3 parts per thousand.

In other words, suppose you have a globe one meter in diameter and it is (erroneously) a perfect sphere. The error is just a few millimeters, hardly enough to notice or worry about on a globe of that size.

And that globe is much better than any possible projection onto a flat map.

This is what's puzzling to me: instead of arguing about one map projection vs. another, why don't they use globes instead to give a more accurate picture? Then they could get into the interesting discussions about the compromises and errors that all map projections make.


It's funny because Gall-Peters is one of the worst projections in terms of distortion. It doesn't preserve shapes anywhere.


Fun fact I recently learned: about 90% of world population is in the Northern Hemisphere. I expected it to be lop sided, but not that much.

http://bigthink.com/strange-maps/563-pop-by-lat-and-pop-by-l...


Not surprising. The equator runs under the bulk of Africa, through the middle of Brazil and Indonesia. The Southern Hemisphere ends up containing about 80% water, about half the landmass of the Northern Hemisphere. And about half of the Southern Hemisphere's landmass is uninhabitable Australian or Antarctic desert.

The more impressive fact is that half of the world's population lives in a small-ish circle in Asia: http://io9.gizmodo.com/more-than-half-of-the-worlds-populati...


Wait? Schools still use Mercator?! Gall-Peters is even worse!

And the reason was social justice? How how the reason being science? The Robinson and Winkel projections are much more accurate. The planet is spherical, not rectangular.

This is about as idiotic and anti-science as teaching Creationism and Intelligent Design in schools.


Yeah completely agree. The article leads me to think the district made the change for political reasons rather than scientific ones.

If that is true, then that is indeed disappointing. Sure, the kids may gain more insights into cartography/geography, but I wonder if the lesson plan now includes a false narrative of the oppressive white man made his continents bigger because "racism."


West Wing vignette on the Gall-Peters projection

https://www.youtube.com/watch?v=vVX-PrBRtTY


And stop putting north up top every time.

Or even stop aligning with the earths spin occasionally.



TLDR: switching to Gall-Peters rather than Mercator projector for the world map. Apparently, jaws dropped, which speaks volumes about the quality of the education here.

https://xkcd.com/977

(The reason for the hate statement next to Gall-Peters is that the Gall-Peters projection has been at the center of not just one, but multiple serious political scandals over multiple centuries. Furthermore, the people who introduced it lied about it, because the primary reason for Gall-Peters is not mapmaking, or education, but "social justice", whatever that means. Exactly what is wrong in 2016 with using a fucking globe or Google maps (which now has a zoomed-out earth view on the satellite section). Also, please don't politicize map projections, or if you absolutely must, Robinson is the way to go)


What do you mean "don't politicize maps"? Maps are one of the most political things there are, with countless wars and disputes over territories, boundaries, and their importance in navigation and imperialism. I also don't get your claim that it isn't mapmaking—it's a map, look—or education, when maps have a big role in history classes and affect one's worldview. It's about striving for an accurate representation of our globe, and if you're against that because "the evil SJWs!", maybe it's you who needs to stop politicizing things. Regarding Google Maps, not every classroom is equipped with a projector, and a globe would have to be really large for students to see them and you'd need a 2D representation for student printouts anyway.


The controversy is not about where borders lie, the controversy is about which country appears the biggest on the map. How to draw the SAME borders so X appears bigger, that's what were discussing. I assure you those wars and disputes were not about the projection of those maps, but about what was drawn on the maps.

If you want to go for accuracy in worldview, show people a globe. If you want a map, Robinson projection is probably the way to go for "most accurate looking". If you want to cross the dateline, and navigate easily, I'd still go with Mercator I think.


My point was that the whole concept of a map is political, even if the disputes don't directly involve this issue with them. The whole world doesn't use the Mercator projection, they use ones more suited towards representing their hemisphere. That's politics.

As for your last point, the fact that you have to mention the drawbacks and advantages of different maps shows that there isn't actually one right answer. That's politics. Map choice has to accept limitations. You can't get a globe everywhere, the 2D plane is still really popular in our world so it's not a binary choice between "globe" and "Robinson", but rather "what exactly am I looking for in a map". It is politics and you can't just immediately shut down anything deviating from the status quo because "my way is the only way".


I can argue to shut down anything in science that gets changed because of political reasons, because there shouldn't be politics in science.

The further along we seem to get the worse it seems to get though. I did math, statistics specifically, so ... well ever since climate change that's a lost cause. And that's uniformly bad. Bad for the quality of people at university, students and academics. Bad for the science itself. Bad for society (imho). Bad for everyone.

The ONLY merit Gall-Peters has is this supposed "social justice" bullshit. Neither Gall and Peters were honest. Neither of them had anything to contribute to mapmaking. They just wanted attention and money. Get out. Just ... get out. Find a better reason, or please don't bother anyone.


> there shouldn't be politics in science

Politics is unavoidable in science. There was never an era in which the two weren't combined from phrenology to modern-day examples like global warming which you mentioned. To expect science to be free from outside influence is overly idealistic. Science needs funding. That fact alone makes it inseparable.

> The ONLY merit Gall-Peters has is this supposed "social justice" bullshit.

Now you're just being dishonest. Did you miss the whole "equal area" thing?

> They just wanted attention and money.

Yeah map projection creators are rolling in royalties... You tell me to find a better reason and you come up with bullshit like this, ha!


> My point was that the whole concept of a map is political

No, navigation is.


Well yes the Mercator projection was about navigation, but maps are also used in other ways since they represent the world. A common example is to depict territories in disputes. Maps were originally for navigation yes, but that's not their only use.




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