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Google Maps Hacks

simonweckert.com

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Re: Google Maps Hacks

#51

Post by jiux »

nudgeee wrote: post #14

I used to work for a mapping & navigation company that offered a traffic API service. It worked by using anonymized cell phone data to predict traffic patterns. I once heard a story that during peak hour, every five minutes or so the jams on a highway would magically disappear then reappear. After some head scratching, turns out there is a train track inbetween the lanes of the highway full of high speed commuters th…

Edge cases like this make work (if that is what one calls it) fun, you know it? Not cynical, but rather true joy in a unique and unexpected challenge.

Re: Google Maps Hacks

#52

Post by RivieraKid »

onionisafruit wrote: post #22
nudgeee wrote: post #14

I used to work for a mapping & navigation company that offered a traffic API service. It worked by using anonymized cell phone data to predict traffic patterns. I once heard a story that during peak hour, every five minutes or so the jams on a highway would magically disappear then reappear. After some head scratching, turns out there is a train track inbetween the lanes of the highway full of high speed commuters th…

How did you fix that? I’ve been wondering how google and the others differentiate between cars on the free vs express lanes.

That's quite easy and there are different ways to do it, the first that comes to mind is using location history.

Re: Google Maps Hacks

#53

Post by kayoone »

ody4242 wrote: post #25
WilTimSon wrote: post #6

Wow, I never actually stopped to think about the way Google determines traffic but it seems so obvious now. This is a very simple but cool trick, I'd expect to see something like this in an action movie where people need to reroute an important car to a particular street. Anyone have any idea how often this data is updated? So if the guy runs through a street with a cart and it turns red, when will it show up as clea…

I guess an important piece (conveniently left out of this story) is that it does not work if there are other cars on the road, as these cars quickly invalidate the data coming from the slow cart.

Not sure if a few cars with GoogleMaps users would cancel out the data from 100 smartphones in the cart though.

Re: Google Maps Hacks

#54

Post by stickfigure »

TeMPOraL wrote: post #36
moltar wrote: post #13

Earlier quoted context omitted.

You can probably avoid it by more accuracy somehow. If the road is just for 1 car width, and there are 50 cars in the same radius (because all are inside the cart), it’s an impossible scenario. I think gps accuracy is something like 3 meters, which is about one car length.

The situation could also easily be discovered by probing accelerometers of the phones that travel in groups. Separate vehicles don't exhibit perfectly synchronized acceleration and deceleration, especially not in a traffic jam.

...unless they're on a bus.

Re: Google Maps Hacks

#55

Post by Frost1x »

duxup wrote: post #33

I always wondered about that. I don't think enough people use Google maps in my area for it to be consistent much of the time. Lots of random (not on map) or way out of date slowdows. The reporting feature doesn't seem to do much. Granted otherwise it is a great app, and I don't pretend to have the solutions to the wonkyness, just wonky at times when it comes to identifying traffic issues.

In many locations your Uber/Lyft drivers are farming a lot of fairly reliable data for Google Maps (and Waze).

Re: Google Maps Hacks

#57

Post by pbhjpbhj »

Frost1x wrote: post #49
ody4242 wrote: post #25

Earlier quoted context omitted.

I guess an important piece (conveniently left out of this story) is that it does not work if there are other cars on the road, as these cars quickly invalidate the data coming from the slow cart.

I always assumed an average was performed over instantaneous velocity that fall in network segments. So, it would depend on the relative magnitude and the edge count on the graph in question you wanted to manipulate. For a long very straight road represented as a single edge, I would assume if you had 100 actual cars, you'd get an average of the manipulated data rate and the real flow rate.

It works out to the same thing, more or less, but I'd guessed they used proximity nodes (junctions) and then when you reach another node use the time (discounting outliers).

Then do the calculations at the server for speed and such.

Re: Google Maps Hacks

#58

Post by CrazyCatDog »

asutekku wrote: post #21
unfundiert wrote: post #9

I'm stunned how fast Google Maps detects traffic jams. I assume all those smartphones are running car navigation and as traffic detection works by trusting the clients I fear there's no chance to avoid this kind of exploit. Nevertheless it would be interesting to know what's the ratio of correct / malicious clients to fool the system. That migt highly depend on whether Google implemented any detection of faulty clien…

Google maps runs also a lot of the time on background so no active navigation is required. I wonder if the introduction of background location activity notifications in iOS 13 decreased the amount of traffic data gathered from iPhone users.

I want one app to track my position at all times. I use google because I’m unaware of another—and I figure they have optimized the energy consumption of doing so. Then again, would be thrilled if someone could recommend an alternate way of doing this on iOS (preferably native).

PS this function allowed me to time stamp my location which proved incredibly helpful in a FOFA request with state patrol—got me out of a ticket that should never have been issued!

Re: Google Maps Hacks

#59

Post by filleduchaos »

stickfigure wrote: post #54
TeMPOraL wrote: post #36

Earlier quoted context omitted.

The situation could also easily be discovered by probing accelerometers of the phones that travel in groups. Separate vehicles don't exhibit perfectly synchronized acceleration and deceleration, especially not in a traffic jam.

...unless they're on a bus.

Exactly. A bus is one vehicle, and you don't want to count every phone on it as a separate entity.

Re: Google Maps Hacks

#60

Post by Spooky23 »

netsharc wrote: post #23

An interesting "red but no traffic" phenomenon is in Iceland, with roads which are next to scenery viewing points. The roads are mostly empty in this country, but everyone must've slowed down when they saw the breathtaking scenery, and would pull into the viewing point's parking spot to stop and take pictures. On Google Maps these areas were marked red. On another navigation related topic; I was using Waze in a high-…

This happens on NY 73, which is a road in the Adirondack High Peaks region between the highway and Lake Placid. It’s legit — even though cars are parked, you still need to slow down!

I usually avoid Google maps for traveling in areas that I don’t know. It takes you off on stupid routes that save marginal time (if any) too much. Waze is good for interstate travel, but IMO Apple is better for giving you the “right”, low drama route.

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