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Interactive visualization of commute times for all US cities

trulia.com

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Re: Interactive visualization of commute times for all US cities

#71

Hi, Sha from Trulia here. I worked on some of the frontend aspects of this visualization and would be happy to answer any questions. We're pulling in OSM road data and published GTFS files for public transit routing. I just linked to SF but you can also search for other cities: http://www.trulia.com/local#commute/new-york-ny http://www.trulia.com/local#commute/miami-fl http://www.trulia.com/local#commute/austin-tx

Is this the absolute worst-case commute times? It never takes me that long to commute into/out of miami, or baltimore, or fort lauderdale. More like half the time. DC actually seemed like it went the opposite way as it usually takes an hour and a half to get from VA through the beltway into DC while the map showed only an hour for as far out as Dale City. A half hour (or more) from Petworth into Downtown during rush…

I used to commute from Miramar to Pompano Beach up i95 every day, 45min to 1:30 just to go 18miles.. So I don't see them that far off.

Re: Interactive visualization of commute times for all US cities

#72

Hi, Sha from Trulia here. I worked on some of the frontend aspects of this visualization and would be happy to answer any questions. We're pulling in OSM road data and published GTFS files for public transit routing. I just linked to SF but you can also search for other cities: http://www.trulia.com/local#commute/new-york-ny http://www.trulia.com/local#commute/miami-fl http://www.trulia.com/local#commute/austin-tx

Have you considered making a map where the color at each point is the average commuting time from there to all points within a radius? For example: http://www.jefftk.com/news/2010-11-17.html

The maps you've added are awesome when you know where you're looking at, but if you don't yet have a place picked out then knowing where to look is good too.

A naive way to compute the kind of summary map I'm interested in is to just make the color at each point on your summary map be the average color on your map for a specific place. Something smarter could weight points by their desirability (I care more about how fast it is to downtown than to an arbitrary point in a suburb) but the naive version is pretty useful on it's own.

Re: Interactive visualization of commute times for all US cities

#73

Hi, Sha from Trulia here. I worked on some of the frontend aspects of this visualization and would be happy to answer any questions. We're pulling in OSM road data and published GTFS files for public transit routing. I just linked to SF but you can also search for other cities: http://www.trulia.com/local#commute/new-york-ny http://www.trulia.com/local#commute/miami-fl http://www.trulia.com/local#commute/austin-tx

For the non-technical, what are you using to create/draw the overlay heat maps? I thought it might be some sort of tile server but it seems to be drawn using JS?

Re: Interactive visualization of commute times for all US cities

#75
post #50

Earlier quoted context omitted.

Is this the absolute worst-case commute times? It never takes me that long to commute into/out of miami, or baltimore, or fort lauderdale. More like half the time. DC actually seemed like it went the opposite way as it usually takes an hour and a half to get from VA through the beltway into DC while the map showed only an hour for as far out as Dale City. A half hour (or more) from Petworth into Downtown during rush…

Agreed on DC - the places that I plugged in from northern va. (22102, 22213, 22046, etc.) all seemed to be showing the best-case times. Some places that it says are a 5-10 commute are more like 30-45 minutes at rush hour. Also, not related to the commute times, but the crime rates look strange. At least, it's showing Arlington, VA as almost completely red (very high crime). Maybe the data is right, but that would be…

I checked out gaithersburg, which it claims is > 60 minutes from bethesda. It's about 45 on average, even in typical traffic.

Re: Interactive visualization of commute times for all US cities

#76

I think it's a very awesome idea, and I'm impressed with the visuals. However it seems that several people on here are claiming wildly inaccurate commute times, and I myself have noticed this as well. I think part of the problem is that it is hard to get a full understanding of what rush hour traffic is like, and that the actual volumes of traffic and slowdown differ depending on locality and road. Sever places, incl…

Public transit estimates from Outer Sunset to Financial District and from Outer Sunset to Fort Mason are quite accurate.

Re: Interactive visualization of commute times for all US cities

#77
post #73

Hi, Sha from Trulia here. I worked on some of the frontend aspects of this visualization and would be happy to answer any questions. We're pulling in OSM road data and published GTFS files for public transit routing. I just linked to SF but you can also search for other cities: http://www.trulia.com/local#commute/new-york-ny http://www.trulia.com/local#commute/miami-fl http://www.trulia.com/local#commute/austin-tx

For the non-technical, what are you using to create/draw the overlay heat maps? I thought it might be some sort of tile server but it seems to be drawn using JS?

Hi, Talin from Trulia here.

For commute, our heatmaps are rendered in canvas, based on JSON data from our servers. This allows for the efficient slider.

We also have static image tiles, for certain (ahem) browsers that don't support canvas. The downside is that they can't use the slider.

Re: Interactive visualization of commute times for all US cities

#79
post #71

Earlier quoted context omitted.

Is this the absolute worst-case commute times? It never takes me that long to commute into/out of miami, or baltimore, or fort lauderdale. More like half the time. DC actually seemed like it went the opposite way as it usually takes an hour and a half to get from VA through the beltway into DC while the map showed only an hour for as far out as Dale City. A half hour (or more) from Petworth into Downtown during rush…

I used to commute from Miramar to Pompano Beach up i95 every day, 45min to 1:30 just to go 18miles.. So I don't see them that far off.

But go to Miramar and look at how the heat is drawn. Huge swaths of area off the scales, and then north of that, inexplicably, is the heat again, saying that something five miles away is somehow 60 minutes, but nothing in between could be reached in 60 minutes. It just obviously does not represent an accurate commute time for the local area... it's some generic calculation done which they probably assumed was correct when they tested it because the one city they were looking at's traffic pattern correlated with their algorithm.

And i'm not trying to give them a hard time, really. It's a neat visualization. But for me, practically, I couldn't use this to tell actual commute times, and I think that's apparent based on the other comments on here. You want my opinion? They should crowdsource taxi drivers. Who else would have a better idea what the traffic's like at any given time of day?

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