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Do transportation network companies decrease or increase congestion?

advances.sciencemag.org

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Re: Do transportation network companies decrease or increase congestion?

#61

Post by kuzehanka »

jacques_chester wrote: post #53
javawizard wrote: post #39

Earlier quoted context omitted.

That's fair, but a certain percentage of Uber and Lyft customers are people who would otherwise drive their own car, so any study that removes the effects of Uber- and Lyft-operated vehicles altogether paints an inaccurate picture.

The point is not (so much) the number of cars, the point is the different behaviour . Self-drivers will go as smoothly as they can from one parking location to another. Uber and Lyft drivers will loop until they get a ride and stop disruptively at the beginning and end of each ride.

Stop disruptively? What does that even mean. Do taxis also stop disruptively according to your definition?

> Uber and Lyft drivers will loop until they get a ride

I ride Uber almost every weekday twice a day. I'd say about 80% of the time the driver has their next trip queued up before my trip ends.

What Uber has done for cities is reduce the number of people who drive in to work and then spend 15 minutes looping around looking for a place to park, possibly multiple times each day.

Re: Do transportation network companies decrease or increase congestion?

#62

Post by bb88 »

Barrin92 wrote: post #20
blondie9x wrote: post #14

Link to the study exactly. https://advances.sciencemag.org/content/5/5/eaau2670 Having just read the study the results make sense. The authors look at car ownership reduction. They find that Uber and Lyft are not actually helping with that. We do not observe a meaningful change in car ownership, with an average of 1.08 cars per household in 2010 and 1.10 cars per household in 2016 (36). This is because as people move…

>The question is what is the best response to help the environment? invest in public transit that can transport people in a denser fashion instead of relying on cars. The fundamental limitation of the car is the low amount of passengers / area it can transport. http://i.imgur.com/G7cAK4Y.gif >Is that partially why many cities and countries do not want them to operate in their jurisdiction? Among other things, yes. Bu…

The story for public transportation in most large cities in the US is not awesome.

    1.  Crime
    2.  Forces you to come in contact with people you would not choose to associate with normally
    3.  Public transportation vehicles are often dirty/unclean
    4.  Long waits during off peak times, often, which forces you to revolve your schedule around public transportation
    5.  Commutes are often longer
    6.  Can't get to your destination often without a long walk, or another vehicle
    7.  Usually still requires walking in the rain/hail/snow/sleet/wind/sub-zero temps
    8.  Initial build out and future expansion are very expensive.
Unless those are addressed in new buildouts, public transportation will continue to have the reputation of public housing and public schools in many places.

Re: Do transportation network companies decrease or increase congestion?

#64

Post by sokoloff »

Barrin92 wrote: post #20
blondie9x wrote: post #14

Link to the study exactly. https://advances.sciencemag.org/content/5/5/eaau2670 Having just read the study the results make sense. The authors look at car ownership reduction. They find that Uber and Lyft are not actually helping with that. We do not observe a meaningful change in car ownership, with an average of 1.08 cars per household in 2010 and 1.10 cars per household in 2016 (36). This is because as people move…

>The question is what is the best response to help the environment? invest in public transit that can transport people in a denser fashion instead of relying on cars. The fundamental limitation of the car is the low amount of passengers / area it can transport. http://i.imgur.com/G7cAK4Y.gif >Is that partially why many cities and countries do not want them to operate in their jurisdiction? Among other things, yes. Bu…

Make public transport remotely competitive with private transport on a time basis and people will flock to it in cities. In cities where public transport is effective (many European capitals and pretty much just NYC and select parts of DC and Chicago in the US), people of all strata of life use it because it's time effective to do so. Because "everyone" is using it, it feels (and usually is) reasonably safe, clean, and "normal".

In other cities in the US, it's so broken that people with time pressure and money in their lives don't use it (and so don't particularly support it from a policy/voting perspective either). Predictably, it's no longer "normal" and feels less clean and safe (and might actually be so).

Re: Do transportation network companies decrease or increase congestion?

#65

Post by gamblor956 »

kuzehanka wrote: post #61
jacques_chester wrote: post #53

Earlier quoted context omitted.

The point is not (so much) the number of cars, the point is the different behaviour . Self-drivers will go as smoothly as they can from one parking location to another. Uber and Lyft drivers will loop until they get a ride and stop disruptively at the beginning and end of each ride.

Stop disruptively? What does that even mean. Do taxis also stop disruptively according to your definition? > Uber and Lyft drivers will loop until they get a ride I ride Uber almost every weekday twice a day. I'd say about 80% of the time the driver has their next trip queued up before my trip ends. What Uber has done for cities is reduce the number of people who drive in to work and then spend 15 minutes looping aro…

It really hasn't. People who drive to work park in monthly lots, usually with assigned spots. Uber replaced people driving to restaurants and bars.

Re: Do transportation network companies decrease or increase congestion?

#66

Post by wmij »

NYC area driver here... TLDR the entire article but I'll give my first hand perspective to say that "T" (taxi) and "L" (livery) plated vehicles on the highways in the NY metro area DO significantly add to congestion as the drivers keep their speeds well under the limit while traveling in passing lanes. Frequently I see these non "cab" "T" and "L" vehicles that I assume are "transportation network" company contractors driving unusually slow because they're either on their mobile devices (looking for pickups?) or driving so under the limit that I assume to not break any GPS speed monitoring rules enforced by these "transportation network" companies, or just generally inept.

I'm not advocating speeding by any means, but after driving 500k+ miles in the NYC metro area you can spot the ineptness and/or driving under fear of speed monitoring of these "T"/"L" plated vehicles. All it takes is for one to be driving 45 mph in a 55 zone on a two lane road with an already congested merge ahead, or they travel in the left passing lane at speeds well under the limit preventing other motorists from advancing, or overall poor driving, then it's a chain reaction of braking and delays mounting behind them.

I've always assumed that the monitoring of these drivers adherence to speed limits is the reason why they travel noticeably slower than the average driver in normal traffic. If that's the case it unfortunately causes the average capable driver to become indirectly part of the "transportation network"'s speed monitoring resulting in delays for everybody.

In the relative absence of these "T" and "L" plated vehicles, I've driven in moderate to heavy volumes where the average speeds are in the 60-65+ MPH range. However, when the livery vehicles start to increase within similar volumes of traffic the average speeds seem to drop and the congestion related delays seem to increase.

So if you were to ask me "Do transportation network companies decrease or increase congestion?" My answer would be "yes". Why? Based on my observations, I suspect it's related to the speed monitoring of the "transportation network" company and a tendency of the drivers of these vehicles being inept relative to other non "transportation network" drivers.

Re: Do transportation network companies decrease or increase congestion?

#67

Post by thereisnospork »

gamblor956 wrote: post #65
kuzehanka wrote: post #61

Earlier quoted context omitted.

Stop disruptively? What does that even mean. Do taxis also stop disruptively according to your definition? > Uber and Lyft drivers will loop until they get a ride I ride Uber almost every weekday twice a day. I'd say about 80% of the time the driver has their next trip queued up before my trip ends. What Uber has done for cities is reduce the number of people who drive in to work and then spend 15 minutes looping aro…

It really hasn't. People who drive to work park in monthly lots, usually with assigned spots. Uber replaced people driving to restaurants and bars.

Either way I'd call that a net win for society. Where's the paper that estimates how many dui-related deaths Uber et al has prevented?

Re: Do transportation network companies decrease or increase congestion?

#68

Post by hedora »

matt4077 wrote: post #54
_jal wrote: post #34

Earlier quoted context omitted.

Well, no. Japanese cars are not otherwise distinguishable by their frequent mid-block stop-and-wait actions, for instance, nor for diverting commuters from public transportation.

Read the actual paper. They seem to have used two methods to make the alternative ("counterfactual") scenario more realistic than just "remove Uber cars": - They compare increase in congestion and Uber/Lyft activity for short road segments, and show that these two changes correlate - They compare reality to a model that does not include ride sharing, but does model increased population etc. This (generally well-regar…

Increases in congestion at popular drop off / pick up sites are not necessarily bad. It could be that dropping people off is the new bottleneck because the rest of the road network is less congested, and now there are more trips (i.e., the road is providing more value because it is more efficient).

A study that measured door-to-door time, and the number of passenger-miles per hour would be much more useful.

I’m not sure why traffic engineers refuse to use metrics that are directly related to the quality of the experience for the people using the roads, or the economic value delivered.

Re: Do transportation network companies decrease or increase congestion?

#69

Post by mrerrormessage »

bb88 wrote: post #62
Barrin92 wrote: post #20

Earlier quoted context omitted.

>The question is what is the best response to help the environment? invest in public transit that can transport people in a denser fashion instead of relying on cars. The fundamental limitation of the car is the low amount of passengers / area it can transport. http://i.imgur.com/G7cAK4Y.gif >Is that partially why many cities and countries do not want them to operate in their jurisdiction? Among other things, yes. Bu…

The story for public transportation in most large cities in the US is not awesome. 1. Crime 2. Forces you to come in contact with people you would not choose to associate with normally 3. Public transportation vehicles are often dirty/unclean 4. Long waits during off peak times, often, which forces you to revolve your schedule around public transportation 5. Commutes are often longer 6. Can't get to your destination…

I agree that many of your points present legitimate difficulties with the use of public transit in the US as it currently exists. However, I think that the first two points are just as true for ride share as they are for public transit. Ride share also has crime (see sexual assault scandals https://money.cnn.com/2018/04/30/technology/uber-driver-sexu...) and ride sharing (particularly pool-style) also "forces you too come into contact with people you would not normally choose to associate with"; some people (including myself) see this as a benefit of public/shared transit, not a drawback.

Part of the problem is that public transit scales differently from ride share. The more riders public transit has, the better it gets. The more riders ride share has (beyond a certain point) the worse it gets.

Re: Do transportation network companies decrease or increase congestion?

#70

Post by jacques_chester »

kuzehanka wrote: post #61
jacques_chester wrote: post #53

Earlier quoted context omitted.

The point is not (so much) the number of cars, the point is the different behaviour . Self-drivers will go as smoothly as they can from one parking location to another. Uber and Lyft drivers will loop until they get a ride and stop disruptively at the beginning and end of each ride.

Stop disruptively? What does that even mean. Do taxis also stop disruptively according to your definition? > Uber and Lyft drivers will loop until they get a ride I ride Uber almost every weekday twice a day. I'd say about 80% of the time the driver has their next trip queued up before my trip ends. What Uber has done for cities is reduce the number of people who drive in to work and then spend 15 minutes looping aro…

> Stop disruptively? What does that even mean. Do taxis also stop disruptively according to your definition?

Yes. But the number of taxis has not exploded in 5 years.

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