5 ms·

This is what I believe to be the cause behind most of the anecdotal stories in the comments here. Google Maps gets bombed with fake edits by people who don't wa

by mike_d 3y ago

This is what I believe to be the cause behind most of the anecdotal stories in the comments here. Google Maps gets bombed with fake edits by people who don't want others using "their" road, so in the event of conflicts map providers have to defer to official sources. When I was at Google I tried to track down someone on the Maps team open to adding a "Jeep Mode" that would let you opt-in to routing via roads that were unavailable and telling you why (washed out, poorly maintained, etc). Nobody seemed to like the idea.

AlotOfReading 3y ago
Many people who haven't had the misfortune of working with geospatial data underestimate how unbelievably hard is to make a good map, let alone a global one.
- ImaCake 3y ago
  Is this because of the data quality and difficulties with merging across CRSes or otherwise slightly differently aligned datasets? I dabble in geospatial data for my work in air quality modelling, accuracy for me means being within approximately 10-50 meters. Even under those very loose constraints I find the data handed to me by clients is often not good enough. Incomplete AutoCad dxfs, PDFs, and dubious SHPs all make the work much harder than it needs to be.
  - AlotOfReading 3y ago
    It's everything. The problem domain for Google maps is effectively "everything on Earth". I haven't worked with gmaps specifically and can't claim specific expertise there beyond some social conversations with people on the team, but some fun things I've encountered include: * Roads that have no physical delineations (e.g. an entire valley is the road). * Landscape features can change rapidly (e.g. forest fires rendering roads unusable on a minute-by-minute basis). * Landscape features can change slowly (e.g. erosion, continental drift) * Landscape features can change slowly and rapidly (e.g. features on glaciers). * Data that's flat out wrong for political reasons (e.g. disputed territories, GCJ-02, hidden "things"). * Data that's flat out wrong for technological reasons (e.g. GPS jamming). * Things that are named in languages without written forms. * Things that have official names other people consider offensive (e.g. Piestewa peak). When you make a map, all of these and more become your problem. Every edge case anywhere in the world is potentially something you have to worry about.
  - cwmma 3y ago
    In addition to what the other commenter said, disparate sources with incompatible schema, often updated at a glacial pace are a big problem and possibly a root cause of the issue in the article.
- strken 3y ago
  It's quite fun trying to work out where an actual walking track is based on a printed topographic map (has good coverage of advertised official tracks but misses some), OSM (has nearly everything but tends to hallucinate non-existent tracks), the output of a local map-maker (compiles OSM and other sources but sometimes has the same track twice in slightly different places), and Google etc. (doesn't show anything a hatchback can't traverse, but has good satellite imagery that can show some tracks). This weekend I'm going to go explore one of the OSM tracks and see where it's a total hallucination, old and overgrown, or real.
  - RicoElectrico 3y ago
    What do you mean by "hallucinate"? FYI most of the time it's a human drawing what they're seeing on the aerial imagery. I know many instances in which someone mapped a track through a field which subsequently got plowed by the field owner, but otherwise I have no idea. Could you tell any specifics?
    - mike_d 3y ago
      Imagine you draw a line following a trail on a map. Looks good, ship it! Now someone else loads that same line on their computer and it looks like a jagged mess because they are twice as zoomed in on the map as you were. Oops. What about the wide parts vs narrow parts of the trail? Do you represent that as two lines or just keep one down the middle? You send your trail to a friend who overlays it on their map that uses a different datum? How were the photos from the airplane assembled, and how did they represent a round object on a flat image? Did they have a good GPS lock when they took the photos, or did they even bother to check? What if the line you created is to be used 100 years in the future when the center of mass of the earth or magnetic north has shifted, how does your coordinate system account for that? I know just about enough GIS stuff to fit on a few index cards, but I quickly realized it is way more complex than how simple Google Maps makes it out to be.
    - strken 3y ago
      Sorry, hallucinate in the sense that the map says there's a track but there isn't anything there, whether or not it was drawn by a human. I meant it as an allusion to the map tripping balls but forgot that the overlap with AI terms would confuse HN. With OSM I think a lot of walking tracks are from GPS traces uploaded by volunteers, so maybe sometimes stuff sneaks in. Or maybe the map shows old tracks that have since been erased by rangers. Or maybe there's a nearby track that has been marked down in the wrong place.
macintux 3y ago
Thanks for trying. I don’t use Google Maps, but if they had a Jeep Mode I’d absolutely use it. Of course, every now and then Google does send someone down the path less travelled by. One day while exploring a remote area and reaching the point where flooding prevented me from going farther, a couple pulled up in some massive SUV, having driven down a road that must have given them pause.
- denton-scratch 3y ago
  Driving from Oxford to Swanage via Poole, looking at the satnav, I noticed that we were passing near to the village of Middle Wallop, and commented on it to my driver (bec ause it's a cool name). We started getting directed down stranger, narrower roads, until we came to a muddy farm track in a tiny village, at which point the satnav announced "You have arrived". We were only halfway to Poole. I must have momentarily touched the satnav screen, and inadvertently reset the destination to Middle Wallop. On the same trip, on arriving at Poole, we should have taken the ringroad; but the driver ignored my navigation directions, and we ended up on a highway into Poole centre. I told the driver to just do a U-turn, and return to the ringroad; then the satnav announced "Board the ferry". We looked at one another, simultaneously saying "What ferry?" Then we looked up, and there was a car-ferry, loading up. So off we sailed to Swanage. Better than taking the ringroad.
rocqua 3y ago
I figured it was a 'smarter' system based on image recognition of satellite data. Or perhaps based on location data of people traveling. I guess this option is much simpler. And it is so frustrating, because it is almost easy to fix, if only you knew the real data source. Especially if it is a local government, they should be quite responsive.
michaelt 3y ago
Doesn't Street View mean they have images showing where the gates and private road signs are?

by mike_d 3y ago

AlotOfReading 3y ago

Many people who haven't had the misfortune of working with geospatial data underestimate how unbelievably hard is to make a good map, let alone a global one.

ImaCake 3y ago
Is this because of the data quality and difficulties with merging across CRSes or otherwise slightly differently aligned datasets? I dabble in geospatial data for my work in air quality modelling, accuracy for me means being within approximately 10-50 meters. Even under those very loose constraints I find the data handed to me by clients is often not good enough. Incomplete AutoCad dxfs, PDFs, and dubious SHPs all make the work much harder than it needs to be.
- AlotOfReading 3y ago
  It's everything. The problem domain for Google maps is effectively "everything on Earth". I haven't worked with gmaps specifically and can't claim specific expertise there beyond some social conversations with people on the team, but some fun things I've encountered include: * Roads that have no physical delineations (e.g. an entire valley is the road). * Landscape features can change rapidly (e.g. forest fires rendering roads unusable on a minute-by-minute basis). * Landscape features can change slowly (e.g. erosion, continental drift) * Landscape features can change slowly and rapidly (e.g. features on glaciers). * Data that's flat out wrong for political reasons (e.g. disputed territories, GCJ-02, hidden "things"). * Data that's flat out wrong for technological reasons (e.g. GPS jamming). * Things that are named in languages without written forms. * Things that have official names other people consider offensive (e.g. Piestewa peak). When you make a map, all of these and more become your problem. Every edge case anywhere in the world is potentially something you have to worry about.
- cwmma 3y ago
  In addition to what the other commenter said, disparate sources with incompatible schema, often updated at a glacial pace are a big problem and possibly a root cause of the issue in the article.
strken 3y ago
It's quite fun trying to work out where an actual walking track is based on a printed topographic map (has good coverage of advertised official tracks but misses some), OSM (has nearly everything but tends to hallucinate non-existent tracks), the output of a local map-maker (compiles OSM and other sources but sometimes has the same track twice in slightly different places), and Google etc. (doesn't show anything a hatchback can't traverse, but has good satellite imagery that can show some tracks). This weekend I'm going to go explore one of the OSM tracks and see where it's a total hallucination, old and overgrown, or real.
- RicoElectrico 3y ago
  What do you mean by "hallucinate"? FYI most of the time it's a human drawing what they're seeing on the aerial imagery. I know many instances in which someone mapped a track through a field which subsequently got plowed by the field owner, but otherwise I have no idea. Could you tell any specifics?
  - mike_d 3y ago
    Imagine you draw a line following a trail on a map. Looks good, ship it! Now someone else loads that same line on their computer and it looks like a jagged mess because they are twice as zoomed in on the map as you were. Oops. What about the wide parts vs narrow parts of the trail? Do you represent that as two lines or just keep one down the middle? You send your trail to a friend who overlays it on their map that uses a different datum? How were the photos from the airplane assembled, and how did they represent a round object on a flat image? Did they have a good GPS lock when they took the photos, or did they even bother to check? What if the line you created is to be used 100 years in the future when the center of mass of the earth or magnetic north has shifted, how does your coordinate system account for that? I know just about enough GIS stuff to fit on a few index cards, but I quickly realized it is way more complex than how simple Google Maps makes it out to be.
  - strken 3y ago
    Sorry, hallucinate in the sense that the map says there's a track but there isn't anything there, whether or not it was drawn by a human. I meant it as an allusion to the map tripping balls but forgot that the overlap with AI terms would confuse HN. With OSM I think a lot of walking tracks are from GPS traces uploaded by volunteers, so maybe sometimes stuff sneaks in. Or maybe the map shows old tracks that have since been erased by rangers. Or maybe there's a nearby track that has been marked down in the wrong place.

macintux 3y ago

Thanks for trying. I don’t use Google Maps, but if they had a Jeep Mode I’d absolutely use it. Of course, every now and then Google does send someone down the path less travelled by. One day while exploring a remote area and reaching the point where flooding prevented me from going farther, a couple pulled up in some massive SUV, having driven down a road that must have given them pause.

denton-scratch 3y ago
Driving from Oxford to Swanage via Poole, looking at the satnav, I noticed that we were passing near to the village of Middle Wallop, and commented on it to my driver (bec ause it's a cool name). We started getting directed down stranger, narrower roads, until we came to a muddy farm track in a tiny village, at which point the satnav announced "You have arrived". We were only halfway to Poole. I must have momentarily touched the satnav screen, and inadvertently reset the destination to Middle Wallop. On the same trip, on arriving at Poole, we should have taken the ringroad; but the driver ignored my navigation directions, and we ended up on a highway into Poole centre. I told the driver to just do a U-turn, and return to the ringroad; then the satnav announced "Board the ferry". We looked at one another, simultaneously saying "What ferry?" Then we looked up, and there was a car-ferry, loading up. So off we sailed to Swanage. Better than taking the ringroad.

rocqua 3y ago

I figured it was a 'smarter' system based on image recognition of satellite data. Or perhaps based on location data of people traveling. I guess this option is much simpler. And it is so frustrating, because it is almost easy to fix, if only you knew the real data source. Especially if it is a local government, they should be quite responsive.

michaelt 3y ago

Doesn't Street View mean they have images showing where the gates and private road signs are?