Comment by velcrovan | Hacker News Reader

Comment by velcrovan | Hacker News Reader

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There is another big problem with W3W that Terence doesn’t mention: it isn’t scalar.

From another W3W-criticism blog post (https://mwfrost.com/space-is-scalar.html):

“An addressing system is successful insofar as it enables us to execute the suite of cognitive tasks that constitute navigation. Associating a destination with its location on the earth is only one of these chores.

“If you have a powerful computer in your pocket, and you want to use your brain to remember and then use your voice or a text message to share a geographic location with someone else who also has a powerful pocket computer, what3words has got you covered. If you want to infer how far that location is from another location, or which roads might connect to it, you are out of luck. Building an addressing system is difficult, expensive work specifically because legitimate addresses embed so many levels of hierarchical categories and scalar proportions for us. Remembering coordinate locations is cognitively burdensome, but the signifiers retain some meaning relative to one another. You can tell the search and rescue team that you’ve twisted your ankle at ringleader.kilt.comedians, but as soon as you’ve moved 3 meters east, you’re at since.duplicates.backswing, and the technologically-enhanced mnemonic crutch has exhausted its usefulness. Augmenting one cognitive task in a manner that debilitates the constellation of surrounding faculties is not the right way to apply technology to our problems.”

> You can tell the search and rescue team that you’ve twisted your ankle at ringleader.kilt.comedians, but as soon as you’ve moved 3 meters east, you’re at since.duplicates.backswing, and the technologically-enhanced mnemonic crutch has exhausted its usefulness.

This represents my disappointment as well. When I initially heard of the system, I thought it was hierarchical; the first word describing some larger chunk, the second describing a chunk within that chunk, and the third describing the 10' x 10' block nested at the bottom. That would have been a fairly cool thing; you could easily go for less precision in order to represent a larger space -- your neighborhood, for instance. Instead, it just feels entirely non-intuitive for a system that seems to have been created to offer mnemonic names for spaces.

Perhaps there are technological limitations to the problem that I can't see that prevent a hierarchical solution from being possible or feasible. But I just see little value in an 'addressing' system where one cell's address is totally unrelated to the cells adjoining it.

edit: I've just found w3w's justifications for a non-hierarchical system on their site and they seem weak to me, but who knows, I'm no expert on the matter. -- https://support.what3words.com/hc/en-us/articles/207768985-W...

Our startup offers a geohash phrase that is hierarchical in nature. You can find the docs at: qalocate.bamsaas.com/whitepapers

How does Google's Plus codes fair in comparison with W3W? It's apparently open-source: https://plus.codes/developers

Here's a link to a Wiki page, in the repo for Open Location Code (prior name for Plus Codes), where they compare it against numerous location encoding systems including W3W.

https://github.com/google/open-location-code/wiki/Evaluation...

For W3W, they say:

- The codes may be pseudo-randomly generated and so nearby places may have completely different codes.

- It may be possible for multiple people to apply for codes for the same location and for different codes to be generated.

- Making a mistake with a code may simply display somewhere else - for example, on What3Words, "banana rabbit monkey" is a location in Argentina, "banana monkey rabbit" is in Russia.

- [It charges] money either for granting a code, for resolving codes or for allowing users to select their own short code.

- [It does] not work offline and [has] a single provider.

Plus Codes has respective advantages for each of these points, i.e., it's not proprietary; can be encoded/decoded offline; nearby places have similar codes; codes can be made longer for more accuracy; excludes easily confused characters; etc. Overall I found the article makes a convincing case for Plus Codes.

This is my main complaint I can intuitively know, using rules of thumb, if a lat lon is within 100 miles, on this hemisphere, etc.

Is "angry ape alligator" right next door or in Europe? No idea. Which fire station do we relay a call to? I don't know, let's ask w3w servers (during an emergency ... )

To the precision that I want to get someone to help me when I'm trapped in a car, you really only need a few significant digits of lat/lon (.YYYY/.ZZZZ) will get you to within 1 km most of the time. The left-of-decimal numbers are not needed if you are calling local 911, as an increment there shifts by a hundred km.

I don't see the relevance of that complaint. People don't memorize their current lat long to 16 sig figs either. You'd still need a gps device or a paper map without w3w.

I think the point is that ringleader.kilt.comedians and since.duplicated.backswing have no relation at all to each other, and don't communicate to the user their spatial relationship. On the other hand, you could infer that 1234 W Something Rd is nearby 1238 W Something Rd.

EDIT: Also, given a set of lat/long coordinates, regardless of the precision, you could infer their spatial relationship as well.

Yea, in LL, 1 second of arc at the equator is about 101 feet or 31 meters which means it's pretty easy to figure out relative coordinates, particularly N/S. Even UTM/MGRS is better in this respect.

That UTM/MGRS even exits seems to be lost on most pitching W3W.

For great circles the metric ratio is close to 40000km/360. A simple trick would be converting to 400gon first¹, but even using 111 Km per degree is a useful approximation.

So 0.01 decimal degree difference in latitude is always 1.11km or roughly 1km. All you need to remember is your length of 1 degree longitude at given latitude which is the following basic trigonmetric relation:

0.01deg = cos(lat) * 1.11km

Cheap linear approximation will do well here too. In South to North order: So usually factor down to 0.8 to 0.7 (38 to 48 Miles) if you live anywhere in the continental US. For Europe it's 84km in Rome, 72km in Paris, 69 in London, 67 in Berlin and 56km in Stockholm

And for approximating local distances it's simply those metric deltas with pythagoras, no need for Haversine or even non-spherical earth models here.

The most important relation for anyone who is into earth and the metric system, is that it's 10M meters or 10,000 km from pole to equator per original definition. You dont even need to remember the earth radius, since that's also defined by 4x10,000km/2π historically.

¹It's a shame that the metric revolution stopped short of Gradians, when it comes to full metric convenience here.

https://en.wikipedia.org/wiki/Earth%27s_circumference#Histor...

"you could infer that 1234 W Something Rd is nearby 1238 W Something Rd."

Don't overestimate that. There are nasty exceptions where the street disappears and continues elsewhere without a significant gap in house numbers, especially in cities with a long history.

Don't throw the baby out with the bathwater here. Being able to naively navigate city -> street -> number is incredibly useful, and that it is occasionally broken doesn't make it an undesirable feature.

It's more than occasionally broken, there's billions of people living in spots where it doesn't work.

Billions? You've found navigation by street number to be unreliable in 20+ % of locations?

Either way, it does work for several billion other people.

I haven't personally found it to be the case, but I do know that people in much of the developing world simply don't have/use street addresses like are common in the "West".

Just because you use a system like W3W or even just lat/long for a rural address in a developing country, doesn't really mean you will easily be able to navigate to it. Many rural roads don't have names/numbers and may not even be marked on mapping software. Navigating to these kinds of places takes local knowledge (or at least a GPS, a recent topo map, and careful planning) to get to.

That's why an address consists of more than a street name and a number. It includes town, province/state, postal code, and country. When given two actual complete addresses, it is indeed possible to infer relative distance with reasonable accuracy, exceptions notwithstanding. (And I live near St Paul Minnesota!)

Even granting that your “nasty exceptions” comprise fully half of all complete addresses, that would simply mean that a normal addressing scheme is better than W3W 50% of the time and no worse in all other cases.

I believe the point is that W3W have no relationship between each other - which is probably inherent, as I assume it's a hash of some kind. You can't do anything meaningful with two W3W addresses, even though they may be literally adjacent to each other.

A common feature of most addressing systems is being able to infer relative distance - this is usually true of even street address. (Yes, I am aware this is not always true, and yes, I am aware there are hilarious counter-examples. I don't think that changes the point.)

With lat/long, you don't need GPS, a paper map is surprisingly effective -- and, in what is the point here, with a paper map (or GPS), you don't need a link to What Three Words' servers. There isn't a good use case for a mnemonic for lat/long that loses the latter's spatial-relationship information.

Above all, the weird thing about W3W has always been that if you have the device to do the lookup, you have the device to exchange and store long and not particularly memorable strings of numbers...

If, by w3w you mean gps-capable device. Like a phone. Which can give you those digits. And if connected to the internet to query w3w's database, can send your precise location.

There's also the old country directions method - navigate by Landmarks. If your emergency services operator is familiar with the geography of their area, this becomes much easier. If you are similarly familiar, this can be very quick.

"Timmy fell down the well by the old mine on the edge of town! Good girl, Lassie."

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