Strava heat map oddities and insights

[lordofthemark]

You can compare 2014 to 2015.

http://labs.strava.com/heatmap/2014-2015.html#13/-76.99914/38.90312/gray/bike

1. There is a big increase in cycling on North Hampton near Park Center. It is not just me, because Park Center Drive itself does not even show up as being ridden. I cannot see any particular closures on other routes that would cause it. The new bike lanes on a road that was already relatively bike friendly, seem to have made a big difference. Similarly either the Wheeler lanes had an impact or Port City Brewing has gotten more popular. Potomac Avenue has gotten busier (new development) but the advisory lanes in Potomac Greens seem to have made no difference (at least to Strava users)

2. You can really see the impact of the road closures at NVCC Alexandria, and where people have detoured to.

3. Some folks are already riding through Army Navy Golf Club. About as many as going through Arlington National Cemetary. How is this possible? I mean I would expect people riding in semilegal places, like the riverwalk in the Navy Yard, or Washington Harbour, but I thought the Country Club was seriously off limits?

4. A lot more people took the airport detour than the Eads Street detour to avoid the mulch.

5. Not much if any increase in riding within Tysons, but a big boost in riding from McLean to the McLean metro station. Take note, FABB.

6. Big increases on the streets of DC, in the places you would expect. Some of course might be increased Strava market penetration.

Topic

[worktheweb]

@Tim Kelley 131833 wrote:

Excellent thinking–you’re probably right on that. And then why does the line fade out so much in the southern half?

This is PURE speculation, but it looks like the fade out is happening just south of “South Thimble Island” which is where the rest area and restaurant is, in fact there is a tiny hot spot on the island. Perhaps the people who were riding from the Delmarva stopped to use the facilities and realized they left Strava on and rectified the situation before continuing? I would imagine there would be more people riding the Delmarva than down in VA Beach/Norfolk. Who knows.

[Raymo853]

@Tim Kelley 131823 wrote:

Yes. And can you confirm that Strava uses wifi maps, triangulation from cell towers, and their own user location heatmaps to record tracks?

I assume Strava just uses the location as calculated by Android or IOS and does not directly access the GPS receiver and calculation algorithms. I actually wonder if Apple or Google would approve “normal consumer” apps that do unless the apps are very focused. Allowing apps to ignore your heavily researched and invested in datasets would defeat the purpose of having a smart phone OS.

Such an app is being marketed currently by Trimble Navigation. I am not sure if it is for sale yet, but it is for Android and IOS and directly accesses the GPS receiver and ignores the other location sources.

[Tim Kelley]

You assume, or you know? And I suppose when your phone is on airplane mode Strava is fully using just GPS?

[hozn]

I am certain that Strava uses the GPS. For one, it is far, far more accurate than cell tower based location services and it continues to work with that same level of accuracy out in the country where there wouldn’t be wifi maps.

I do not know if Android exposes multiple tiers of location so that apps can merely request the level of granularity that they need. I suspect so, but I will read up on it.

Edit: yes, Android provides APIs for the GPS or network-based location services; apps can choose which strategy/ies they wish to use. http://developer.android.com/guide/topics/location/strategies.html There is also a higher-level API that abstracts out the details and chooses the best strategy.

[Raymo853]

I too assume Strava uses the GPS capabilities of phones, but I also assume it also uses the other location methods when they are available. Yes most phones allow you to have the GPS antenna on while on airplane mode suppressing any cell or WiFi type location stuff.

[hozn]

@Raymo853 131887 wrote:

I too assume Strava uses the GPS capabilities of phones, but I also assume it also uses the other location methods when they are available. Yes most phones allow you to have the GPS antenna on while on airplane mode suppressing any cell or WiFi type location stuff.

I’m actually not sure that’s true. There’s certainly no requirement that they use other location strategies. We could ask the developers, I suppose But, as evidence, my previous phone had a really crappy GPS and Strava would refuse to record a ride, saying that the GPS signal was inadequate. The phone worked great for detecting cell networks and wifi; it was only the GPS component that was flaky. (Navigation in the car was also very bad, since it was only able to get coarse-grained locations and would frequently assume I was on nearby roads.)

[Tim Kelley]

@Raymo853 131887 wrote:

I too assume Strava uses the GPS capabilities of phones, but I also assume it also uses the other location methods when they are available.

You’ve used the word “assume” three times in your past two posts. Do you actually know or are you just guessing?

[Raymo853]

@Tim Kelley 131891 wrote:

You’ve used the word “assume” three times in your past two posts. Do you actually know or are you just guessing?

It is hard to be sure since Apple, Samsung, Motorola, Verizon, AT&T , …… do not release this information. They actually go out of their way to hide it.

My attempted message? Smart phones are great for what most of us use them for, finding stuff in the developed World and tracking ourselves. But people need to understand they do not offer the greatest accuracy or precision in location, that is why short segments on Strava are such a joke.

Regardless of this tangent subject, I still would like Strava to address the differences in map tiles used to build their heatmaps.

[LeprosyStudyGroup]

I used strava to track my run across the bay bridge during the 10k race this year, maybe a few others did that but forgot to switch it to run mode?

[Author]

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