What happens when What3Words gets lost in translation?

What3Words, nan website and app that translates beingness coordinates into short memorable combinations of words, has been praised and criticized complete nan years.

Now a machine intelligence astatine nan University of Exeter successful nan UK has formally described successful a insubstantial really disorder tin originate from nan geocoding algorithm utilized by What3Words, and questioned its fittingness for directing emergency services to incident locations.

What3Words (W3W) dates backmost to 2013. It's an app that uses a proprietary geocoding strategy to representation geographic coordinates to a group of 3 words, because agelong numbers thin to beryllium much difficult for group to retrieve and pass than words.

The strategy useful by dividing nan world into a grid of 3 metre squares and assigning 3 words from a information group of astir 40,000 words to each square. Thus nan latitude and longitude of New York City Hall (40.712772, -74.006058) maps to clip.apples.leap, which typically would beryllium easier to recall, say, aliases type into a mobile device.

The app, according to nan company, is utilized successful 170 countries by thousands of businesses arsenic good arsenic governments and NGOs. It has received endorsements successful nan UK from nan Automobile Association (AA) and immoderate emergency work groups, which person advised travelers to usage nan W3W app successful lawsuit they request to pass their whereabouts. The makers of nan app itself person described W3W arsenic an "additional tool" that emergency services astir nan world tin usage to find callers.

But nan app is besides nan taxable of ongoing criticism, documented connected nan website What 3 Words is simply a Mess. The tract lists various news and societal media reports that mention problems arising from nan usage of W3W addresses.

Pointing to these concerns, Rudy Arthur, a elder teacher successful information subject astatine nan University of Exeter, has analyzed nan W3W geocoding algorithm, arsenic described successful nan company's patent filing because nan company's codification is closed to scrutiny.

"If W3W is wide adopted by emergency services it must beryllium taxable to rigorous evaluation," he explained successful a preprint paper titled: "A Critical Analysis of nan What3Words Geocoding Algorithm."

The Register contacted Arthur to talk astir his findings but he declined, stating that he hopes nan insubstantial will beryllium published successful an world diary and that he would alternatively hold until nan adjacent reappraisal process is complete earlier discussing nan work.

Arthur successful his insubstantial says that while he's not alert of anterior general world study of W3W, location person been nationalist posts from method experts who person raised concerns astir nan geocoding scheme. For example, 2 years ago, penetration tester Andrew "Cybergibbons" Tierney argued nan algorithm tin create disorder if group incorrectly pluralize/depluralize words aliases misinterpret spoken words for homophone spellings.

Tierney noted that W3W has claimed "people confuse plurals only astir 5 percent of nan clip erstwhile proceeding them publication retired loud," which he said intends that nan chance of a W3W reside being confused conscionable connected nan ground of plurals is 1 successful 27.

W3W, connected nan different hand, says nan anticipation of disorder is overmuch much remote.

"Let's opportunity location are 10,000 perchance confusable combinations ambiguously adjacent to each different successful nan UK," nan institution said erstwhile addressing these concerns successful 2021. "That is 1 successful 2.5 cardinal (0.00004 percent) wide chance of hitting a quadrate that could beryllium considered to person a adjacent quadrate pinch a confusably akin address."

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W3W besides asserted: "The overwhelming proportionality of similar-sounding 3 connection combinations will beryllium truthful acold isolated that an correction is obvious."

The consequence of specified disorder successful nan discourse of emergency services includes scenarios for illustration ambulances directed to nan incorrect location, to nan imaginable detriment of those successful request of assistance.

Arthur's insubstantial identifies 14 chopped modes successful which errors tin beryllium introduced successful nan oral aliases written transmission of connection triplets. These see typos, homophones, autocorrect substitutions, location pronunciation variations, uncertainty astir connection boundaries ("dogs.tart" aliases "dog.start"), and truthful on.

As an illustration taken from Arthur's insubstantial of conscionable homophone correction possibilities, nan location "arose.recede.home" has a disorder group that consists of "arrows.recede.home," "arose.reseed.home," and "arrows.reseed.home." That is to say, these are imaginable soundalike errors that could beryllium introduced erstwhile attempting to convey a W3W reside to different person.

I estimate 20-25 percent of addresses person much than 3 different addresses pinch which they could beryllium confused

It's difficult to measure nan wave of these correction modes, nan information intelligence says, owed to nan restrictive position of nan W3W license. He has, however, made the codification for his information analysis public.

"I estimate 20-25 percent of addresses person much than 3 different addresses pinch which they could beryllium confused, considering only homophones and typing errors," Arthur says successful his paper. "Thus it whitethorn beryllium very difficult, if not impossible, to decipher a miscommunicated reside pinch nan existent system."

"Contrary to what W3W claim, this activity has shown that galore confusable W3W addresses are apt to beryllium and has identified immoderate superior problems pinch nan W3W algorithm. However, while showing that galore confusable pairs exist, this activity does not show that they will beryllium confused."

Pointing to nan various different geocoding systems that are being utilized – GeoHash, Natural Area Codes, Plus Codes (a.k.a. Open Location Code), nan Military Grid Reference System, and nan Maidenhead Locator System – Arthur suggests nan Ordnance Survey National Grid reference strategy would beryllium much suitable for UK emergency services applications.

What3Words did not respond to requests for remark but has antecedently told nan BBC that quality correction is "a anticipation pinch immoderate type of tool." ®