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Suburban Ride-Sharing Is Mathematically Unlikely

citylab.com

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Re: Suburban Ride-Sharing Is Mathematically Unlikely

#3
This is probably about as accurate as the Drake equation.

At the company I work at in the UK, probably 80% of people lift-share. Admittedly that is unusual but still. The article makes several mistakes anyway:

* "8 out of 31000" is one source to one destination - so it is very misleading

* They don't realise that people might be willing to work different hours in order to find a lift share

* 10 percent seems unoptimistic

Re: Suburban Ride-Sharing Is Mathematically Unlikely

#4
The article has two insights, which are kinda related in an surprising way.

One is tangentially mentioning that car poolers almost always know each other and will not go with random strangers; I thought to myself, yes, I am not young and I cannot remember ever hearing or seeing first hand a "hitchhiker" style car pool although coworkers helping each other out (critically, without a dedicated app/service middleman) is almost normal. The insightful part is the successful ride sharing services actual business model is psychologically tricking users into pretending to be taxi drivers and taxi customers rather than some random dude picking up anonymous hitchhikers which is what they really are.

The second semi-related insight is when the free market numbers won't work, just demand the government socially engineer a private profit. Specifically the part of the article where the government should artificially manipulate parking prices to make him the billionaire he is entitled to be because he is so much more deserving of a billion than everyone else. As the article implies, the concept of suburban ride sharing IS mathematically impossible as defined and the only hope for that sector is winning some kind of "dictator for a day" lotto to basically oppress and dominate the inhuman locals.

What ties them together is the concept of LARPing, live action role play. In the first insight from the article, you can successfully run a middleman transport business, basically an online semi-illegal unlicensed gypsy cab dispatcher service, by convincing both participants to LARP that they're taxi drivers and passengers. In the second insight from the article, aside from all this complicated mathy stuff which is none the less true, you can tell a business sector is dead when the only serious business plan first involves LARPing like becoming dictator for life or mass social engineering or whatever other wish fulfillment.

The esoteric message of the article, as opposed to the mathy exoteric message, is the sector is dead because the only participants are the business hustler equivalent of joining the SCA and mistakenly thinking that means you're actually the municipal government, rather than the reality of getting drunk with friends in costume. Which is fun, but don't confuse it with actual political rule.

Re: Suburban Ride-Sharing Is Mathematically Unlikely

#5
post #2

Where I live, commuter trains are packed, though (Europe). How can that be? The same logic should apply to commuter trains as to cars?

I think people are significantly more likely to choose to live near a train than they are to choose to live near someone who works near where they work. Among other things, it's a much more concrete consideration when house hunting.

Re: Suburban Ride-Sharing Is Mathematically Unlikely

#7
post #2

Where I live, commuter trains are packed, though (Europe). How can that be? The same logic should apply to commuter trains as to cars?

It's because Europe doesn't do suburbs and parking lots the same way that America does. Densified development around transit services will result in more people taking those services. Less and/or more costly parking in the city centre will result in fewer people driving. This is how Europe does things.

Basically, the mix of vehicles (cars, trains, driverless cars, whatever) is far less deterministic than the urban development patterns. Build suburbs with homogeneous lot sizes and city centres with a lot of free parking, and the mode choice is more or less a foregone conclusion.

Re: Suburban Ride-Sharing Is Mathematically Unlikely

#8
Here's a super depressing mathematical proof of why the services fail in the burbs:

First the assumption is a car is necessary for living in general. I am very happy for the 0.1% of the population who live in an urban hugbox where they don't need a car, but this is a general argument for 99% of the population or a unicorn sized middleman app.

My garage costs perhaps $50K lifetime, including land, maint, all added together. An online mortgage calculator spat out $290/mo for my garage. I suppose as a fraction of the cost of the house its not ridiculous. Or at 20 working days per month, simply having the possibility to drive my own car costs $20 to park it at home. Use it or not, I'm out $20 per day.

I bought the cheapest toyota out there for my commute. Many people will insist on the largest SUV they can afford, but whatever. Many people will replace their car every two years to show off conspicuous consumption whereas I drive my cars into the ground because I'm super arrogant and rebellious about not impressing other people. Anyway simple straight line capex depreciation of $20K vs 250 commutes per year vs maybe a decade life of the car means each working day the car drops in value $8 no matter if I drive it to work or not.

Being a commuter car instead of a SUV I am kinda cheating on gas expense when I actually drive to work. Figure 40 miles round trip at 80 MPH (I don't live in CA LOL, and flex time a lot) and 40 / 30 mpg = 1.3 gallons burned per commute and we'll pessimistically call the average price of gas over a decade $3 (LOL) so it costs me $4 to actually drive instead of car pool.

Now there are two ways the math argument kills suburban car pooling. The first is I'm out $28/day to commute no matter if I actually commute, car pool, or call in sick. The variable cost is a menial minimal $4 to actually do it. So I do NOT save 100% of the cost of my commute, I only save about 10% of my commute cost by not commuting. Why bother? If I wanted to save 10% I'd be infinitely more likely to get an even smaller car or live in a cheaper area than to give up the convenience of my car for a mere 10% savings. This argument is like people who pay $4000 mortgage and then shiver in the dark because they can't afford the heating bill, its not that turning down the thermostat is a great idea, but its that they obviously demonstrate incredibly bad economic management to end up in a scenario like that.

The other killer is car pooling takes a lot of time, and regardless of how high or low an employer values his feudal servant's time, outside work people seem pretty happy to drop $20+/hr to get drunk or watch theater movies or whatever. So I feel $20/hr is a reasonable valuation of time for the general public. Now lets say car pooling costs 15 minutes extra wasted time at each of four endpoints, for a total of an hour. If you insist on matching up strangers online, they probably don't live or work nearby each other. Now an hour of free time is worth $20, and car pooling will cost me an hour, but save me $4... So car pooling puts me $16 in the lifestyle hole.

So mathematically I don't save much money by occasionally car pooling, and the standard of living is dramatically lower.

I tried to calculate a math model for reliability and dropped it... its hard to compare a nearly 100% reliable toyota vs a very hypothetical service that may or may not match you up after hours and may or may not match you up with weirdo axe murderers or maybe not. Basically you have one system that although expensive is nearly perfectly reliable and nearly perfectly safe, vs a pile of question marks that might ... might ... turn out as good. Maybe. But you can't build a math model off that so I gave up.

Re: Suburban Ride-Sharing Is Mathematically Unlikely

#9
post #3

This is probably about as accurate as the Drake equation. At the company I work at in the UK, probably 80% of people lift-share. Admittedly that is unusual but still. The article makes several mistakes anyway: * "8 out of 31000" is one source to one destination - so it is very misleading * They don't realise that people might be willing to work different hours in order to find a lift share * 10 percent seems unoptimi…

Yea, as soon as I got to the "8 out of 31000" line, I knew the author wasn't being intellectually honest, and I couldn't trust any of the other assumptions he made.

Re: Suburban Ride-Sharing Is Mathematically Unlikely

#10
post #4

The article has two insights, which are kinda related in an surprising way. One is tangentially mentioning that car poolers almost always know each other and will not go with random strangers; I thought to myself, yes, I am not young and I cannot remember ever hearing or seeing first hand a "hitchhiker" style car pool although coworkers helping each other out (critically, without a dedicated app/service middleman) is…

Hitchhiker-style carpooling is alive and well in DC. http://www.slug-lines.com/

All the major arteries into DC from Virginia have HOV lanes. At many major interchanges, there are parking lots. If you want a ride that doesn't take 2+ hours, you park at the interchange and hop in a stranger's car.

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