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Study: carpooling apps could reduce traffic 3x in NYC

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Re: Study: carpooling apps could reduce traffic 3x in NYC

#51

Post by cashmonkey85 »

chongli wrote: post #15
cashmonkey85 wrote: post #11

Earlier quoted context omitted.

I see this in Tokyo. Americans just stuck at home, stranded and helpless because of their culturally reasons. Oh no wait they just use the awesome public transport system. But it's very difficult for them to enjoy such efficience because...you..know...culture

Huh? Americans don't have a cultural aversion to using world class public transit when in a place like Tokyo. They have a cultural aversion to altering their cities in the radical ways that'd be necessary to build a functional public transit. They call this NIMBY.

Reply to the parent comment then. He was the one claiming Americans must drive cars.

My reply was to what's called a "parent" comment. And in that comment was context. And using that context you should understand my comment. They need to be read together. My comment and the parent comment. Read both together. First the parent comment and then my comment, the "child" comment.

Re: Study: carpooling apps could reduce traffic 3x in NYC

#52

Post by CodeSheikh »

chrishacken wrote: post #44
CodeSheikh wrote: post #37

New York City includes Brooklyn, Queens, Bronx and Staten Island as well. Misleading title and perhaps incomplete study if footprint of cabs is not included from those remaining boroughs in this study. If you live in Manhattan, then you don't use cabs as much within Manhattan because subways cover Manhattan pretty well and travel times in cabs are hellish comparing to subway commute. You often use cabs when you commu…

> travel times in cabs are hellish comparing to subway commute Isn't this because of road congestion though? I thought the principle behind the study was to remove all cars except those 3,000 ride sharing vehicles.

Yes, it is one of the factors but not the only one. Others being people commuting in their own cars (yes we have stubborn folks who refuse to take trains), pedestrian traffic (primarily composed of tourists and selfie enthusiasts), never ending construction and repairs in Manhattan, Food carts maneuvering etc. to name a few.

Re: Study: carpooling apps could reduce traffic 3x in NYC

#53

Post by usrusr »

chillingeffect wrote: post #8

This is great news, until we look at the open space and say, "Wow! Now we can fit so many more commuters on these streets." Nature abhors a vacuum. Not to denigrate the science, I respect the math greatly. It's just that NYC culture is about trying to cram the most things in one place. Few open resources like Central Park remain so very long.

But nature seems to just not abhor the "vacuum" left in cars filled with just a single rider hard enough to fill that. This is about finding a lower bound for the vehicles needed to fulfill demand with multi-occupancy.

What I would find even more interesting is if they used the same simulation to determine the number of cars required to fulfill that demand without multi-occupancy, but with the same level of dispatch smarts and similarly strict optimization for the lowest number of cars possible.

Why would this be interesting? There are not 13000 cabs because less would not be able to meet the existing demand, there are 13000 cabs because the market is big enough to support them (and decisions regarding the volume of the medallion system are surely not done with the optimization vigor as researchers looking for an impressive lower bound in a simulation). Hailable transportation is a very special market where more supply only increases instant hailability, but does not have the conventional effect of decreasing prices. And because more supply means more congestion, it can even increase prices (when rates have a time component on top of a distance component) and demand (when permanent congestion makes it unattractive to have a personal vehicle).

Re: Study: carpooling apps could reduce traffic 3x in NYC

#54

Post by knz »

Xixi wrote: post #45
jozzz wrote: post #30

Earlier quoted context omitted.

Except in Paris there are so many cars in use, causing such a huge amount of pollution, that the government had to ban half the cars in Paris from driving on certain days last year.

Isn't the main issue of Paris the lack of wind to blow the pollution away? Combined maybe with the high number of diesel cars? I don't think you'd see this level of pollution in a city like NYC, or really any city near the coast, simply because of the wind.

Isn't LA known for it's smog?!

Being coastal just means you have prevailing winds - if geography is working against you (barrier mountains or a basin) then you will have a pollution issue.

Re: Study: carpooling apps could reduce traffic 3x in NYC

#55

Post by ticviking »

kirykl wrote: post #9
JoeAltmaier wrote: post #2

And a grid of regular bus service could replace every car in LA. That'd be a harder sell though.

LA has a very underrated transport system. You can get pretty much anywhere, it just might take longer than by car, but only by an hour or two. Biggest hurdle is bus frequency, but even the routes on the hour are reliable and usable.

> but only by an hour or two

So if I have a pretty normal set of afternoon errands like, go to the doctor, get groceries, drop groceries off at home and go to my evening meetup, I'm only looking at an extra 4-8 hours of transit time?

An extra 15-30 minutes of transit time(per leg) is basically what is actually sustainable for non-drivers to be able to get multiple things done in a day.

Re: Study: carpooling apps could reduce traffic 3x in NYC

#56

Post by guessmyname »

CodeSheikh wrote: post #37

New York City includes Brooklyn, Queens, Bronx and Staten Island as well. Misleading title and perhaps incomplete study if footprint of cabs is not included from those remaining boroughs in this study. If you live in Manhattan, then you don't use cabs as much within Manhattan because subways cover Manhattan pretty well and travel times in cabs are hellish comparing to subway commute. You often use cabs when you commu…

I didn't know how big New York City was until I went from Central Park (North side) to the Brooklyn Botanic Garden... walking... never again!

Re: Study: carpooling apps could reduce traffic 3x in NYC

#57

Post by Fricken »

Nav_Panel wrote: post #32
Fricken wrote: post #21

Earlier quoted context omitted.

That's the problem with most american cities- grossly inefficient land use policy. Fix land use and effective transportation becomes an afterthought.

It's very hard to "fix" land use once the land is already "in use". Much harder than before the land is developed, at least. LA seems to be doing the right thing: build subway lines/high-density transit, even if it "goes nowhere," and the density will follow.

We've been building our cities wrong for what(?) 80 years or so. We've been aware of it for over 50. Still, there are depressingly few examples where we've been able to meaningfully change course. We don't drive our personal automobiles, they drive us. We ironically associate the car with freedom, yet building for the car renders every other mode of transportation ineffective, at great cost to our wallets, our physical, mental and social well-being, and to our environment.

Re: Study: carpooling apps could reduce traffic 3x in NYC

#58

Post by awjr »

I find the focus on congestion within the transport space to be perplexing. I'm guessing it is to do with the visibility of congestion. Waze recently did a survey and identified the Netherlands as the best place to drive (https://www.waze.com/driverindex).

The Netherlands is also the only western country with a negative obesity trend expected to hit 8% by 2030, currently at 10% vs the UK's 25%. The USA I believe is getting close to 36%.

We can try and blame our diets, however our built environment is creating a public health crisis of inoordinate scale. The car is very much to blame for this.

The car and car sharing is not the answer to traffic. Creating segregated end to end cycle networks with good junctions enabling people to choose to ride up to 5 miles to school/work is absolutely critical to avert this public health crisis.

Re: Study: carpooling apps could reduce traffic 3x in NYC

#59

Post by Justsignedup »

awjr wrote: post #58

I find the focus on congestion within the transport space to be perplexing. I'm guessing it is to do with the visibility of congestion. Waze recently did a survey and identified the Netherlands as the best place to drive ( https://www.waze.com/driverindex ). The Netherlands is also the only western country with a negative obesity trend expected to hit 8% by 2030, currently at 10% vs the UK's 25%. The USA I believe is…

NYC's problem is also distance. Depending on where you're coming from biking could take 1.5-2hrs each way. I enjoy it but the problem is with extreme rising housing costs people are pushed further and further.

Though to be honest, a SAFE biking lane system would be a much welcome gift in NYC. Currently in certain areas I have to work doubly hard to not get killed daily.

Re: Study: carpooling apps could reduce traffic 3x in NYC

#60

Post by source99 »

awjr wrote: post #58

I find the focus on congestion within the transport space to be perplexing. I'm guessing it is to do with the visibility of congestion. Waze recently did a survey and identified the Netherlands as the best place to drive ( https://www.waze.com/driverindex ). The Netherlands is also the only western country with a negative obesity trend expected to hit 8% by 2030, currently at 10% vs the UK's 25%. The USA I believe is…

Much of the academic research I have read (Check out Good Calories, Bad Calories by Gary Taubes) shows the exact opposite to be true.

Our diets accounts for dramatically much higher cause of obesity than our environment and specifically cars.

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