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Analyzing My Google Location History

towardsdatascience.com

105 pointsNicoJuicy26 comments

> I assumed confidence to be the probability of each task. However, often they do not add up to 100. If they do not represent probabilities what do they represent?

The probability of each being true independently?

> How can Google possibly predict activity type between IN_TWO_WHEELER_VEHICLE vs IN_FOUR_WHEELER_VEHICLE ?!

Two wheel vehicles can often make it through traffic, in between cars.

Measuring how much the phone rolled back and forth could be a factor, too. You don’t have to keep a car balanced, you do have to keep a bike/scooter/motorcycle balanced.

I drive a motorcycle in Thailand all the time google is more wrong than right when predicting this.

I'm gonna bet that Thai bike-driving habits are different from those of people in the US, at least in cities.

I going to bet there are more bike driving people with Android phones in places like Thailand, Indonesia, India and the Philippines where on-road behavior is more similar to each other than to the US.

I think it's a pretty hard problem, and we shouldn't be surprised if the accuracy there is low.

Seems feasible to detect a user at above foot speed,that appears to be stopping at intersections but seems to be more immune to congestion than others and label it as a two wheeled vehicle.

https://developers.google.com/android/reference/com/google/a...

It's probably a combination of features, but the suspensions are different, and two wheelers lean when they turn, which should be easy to distinguish from the accelerometer and gyros.

> How can Google possibly predict activity type between IN_TWO_WHEELER_VEHICLE vs IN_FOUR_WHEELER_VEHICLE ?!

Could they be using this from accelerometer data instead of GPS? https://github.com/guillaume-chevalier/LSTM-Human-Activity-R...

https://news.ycombinator.com/item?id=13049143

There are also certain roads/paths that are bike only, through convention (bike lanes) or physical width restrictions.

LOL. There are no such paths in India - Article Author

I've never been to India but presumably you have some parks... However, I do see that google maps has the bicycle overlay greyed out for New Delhi!

I wrote a little script a few years ago to make a nice map out of my location history:

https://dirkjan.ochtman.nl/writing/2012/11/28/tracing-a-path...

> What does the activity type "tilting" mean?

"The device angle relative to gravity changed significantly."

-- https://developers.google.com/android/reference/com/google/a...

I did something like this in a quantified self phase, it's fun to see the location patterns. I was gridding locations into buckets and scoring the entropy over time, to see how diverse the set of locations I was going to was. Long story short, not that diverse. Just over 1 bit was enough! (think: home or work)

We actually did that several years ago in our data viz lab. All of the (willing) lab members tracked their location data and one student developed a way to track and visualize co-occurrences of people over time [1].

Another ways to visualize this kind of information is to use space time cube maps, which turn the time axis into the z-axis for trajectory visualization; GeoTime[2] is the most well known implementation of it AFAIK.

[1] http://profs.etsmtl.ca/mmcguffin/research/2016-gupta-Movemen... [2] https://geotime.com/products/geotime/

it's disappointing that apparently if there is no connection it just throws the data away. I'd prefer if it saved it locally and uploaded when it can

Uhmm, maybe it depends on the phone? I backpacked Europe 4 years ago without a data plan and I have all my location history logged, it seems like it kept it on my phone while offline and then it uploaded it when connected, I used a Galaxy S5 btw.

I'd prefer it to be saved locally or sent to a server of mine with some standard protocol (maybe NMEA 0183 over HTTP POSTs) and never to Google. Of course I could write an app for that (and I did some 8 years ago) but it would be much easier if the OS would cooperate.

By the way, I disabled location services on my devices to prevent at least this form of spying on me.

OwnTracks is an app that does that, https://owntracks.org/ , but I still haven't set up my server to receive the data.

It uses MQTT, which is probably fault tolerant/store data locally if it can't connect to the server right now.

Funny how Google also consider those places where I have stopped just for a minute.

> "My previous phone had some GPS issues, which was leading to my location being shown in Arizona, USA"

Sounds more like your gmail account was compromised

Or you’re getting an IP from somewhere associated with a different region. This happens all the time with my cell connection - it seems the company uses spare Verizon capacity, and when I (or someone else) looks up my 4G is, it’s all over the US with no connection to my actual location.

Or was it that trip to Vegas?

I wish - Article Author

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