Let’s Consider How Self-Driving Cars Impact The Future Of Mass Transit

Dr. Lance Eliot, AI Insider

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Here in Southern California, a key local transit entity is called MTA (Metropolitan Transit Authority) and provides mass transit options for commuters from throughout Los Angeles county. You’ve got light rail, heavy rail, buses, and the like.

Of the nearly one hundred MTA stations used by commuters to get access into the transit system, it turns out that only a few of those stations directly intersect with a second line. This means that you need to hop onto one train, hop off at another station, wait for the next right train, hop on, and maybe then arrive at the final station you were intending to reach. It seems likely you’ll need to make at least two or three such stops and switches, in reality, due to the lack of stations being interconnected with multiple lines.

Many people perceive that it is too confusing to have to make so many switches. They perceive that it uses up too much time, having to make the switches and sit around for the needed waiting times for the next right train.

The less riders on the mass transit system, the less valuable it is having the mass transit system.

It also means that the lack of ridership implies there’s less people taken out of the conventional car traffic pool.

And, thus, the mass transit doesn’t achieve some key stated goals of reducing conventional car traffic, which tends to also reduce pollution, and the mass transit is supposed to produce a lower cost alternative per mile per person traveled.

Looking At The Year 2047 For A Solution

One topic being discussed and debated here in Southern California is the proposed development of a new north-south spine that would run throughout central L.A. and create more intersecting points with the existing stations. According to Metro, the new line would potentially serve 90,000 trips a day and become the busiest light-rail line in the United States.

If all goes well in terms of proceeding to build the new line, it would open in the year 2047.

That’s right, the official ribbon cutting for the first ridership would be about 30 years from now.

For most of us, it’s hard to imagine waiting thirty years for something. If you have small children, they’ll be middle aged by the time the new line is running. If you are middle aged now, you’ll likely be nearing retirement. If you are already retired now, I can only hope you’ll be around to come and see the grand unveiling of the new line.

In terms of construction cost, it’s estimated that it could be around $150 million per mile (totaling a cost of about $3 billion), if built at street level.

Focus on the year 2047.

Place your mind into the future.

The Future Should Include AI Autonomous Cars

What does this have to do with AI self-driving driverless autonomous cars?

Depending upon whom you believe, we’re presumably going to have quite a number of AI self-driving cars on our roadways by the time that the year 2047 rolls around. One notable prediction mentioned in a Fortune magazine article predicted that by the year 2040 that about 95% of new cars sold in the United States will be AI self-driving cars.

If that’s the case, it would tend to suggest that by the year 2047 there will be a plentiful number of AI autonomous cars cruising around our highways and byways.

If we go along with the notion that it won’t be until about 2040 that the predominant new car purchase will consist of AI self-driving cars, it suggests that during the 2020’s and the 2030’s we’ll have a mix of conventional cars and AI self-driving cars, but that conventional cars will still be the dominant mode of car traffic on our roads.

Returning to the matter at-hand, I began by mentioning that the Los Angeles mass transit system is proposing to add a new line at a cost of perhaps $3 billion to $5 billion dollars, and that it won’t be ready until 2047.

Hard-To-Digest Questions About Future Mass Transit

Here’s the million dollar (or billion dollar) question: Do we need more mass transit by the time we reach the mid-2040’s and beyond?

If we’re going to have widespread AI self-driving cars by that same time frame, perhaps we’re pouring money into adding mass transit that will ultimately have been for not.

In other words, yes let’s keep the existing mass transit system going, since we presumably need it during the next 30 years or so for purposes of shoring up the lack of widespread AI self-driving cars, but maybe we should be doing a “gut check” as to starting to build something that won’t come available until a future in which it maybe won’t be needed.

It’s perhaps a bridge to nowhere, as they say.

In any case, any mass transit project that is going to get started now or in the near future, and for which it might take 30 years or more to get built, we probably should look in the mirror and say do we like what we see?

Does it make sense to pump money into such projects?

Though I’ve brought up the question in the context of the Los Angeles mass transit, it seems prudent to ask the same question about any mass transit proposed anywhere in the United States.

Consider The Trade-offs Involved

Another argument in favor of proceeding with massive multi-decades long mass transit projects would be that even if AI self-driving cars are popular by 2047, maybe we will still need mass transit.

Let’s consider that aspect, analyzing the positions both in-favor and opposing to it.

Some believe that with the prevalence of AI self-driving cars, we are going to have a ridesharing-as-an-economy way of living.

This means that ridesharing will be the dominant mode of travel and that we’ll be using AI self-driving cars to do so.

If that happens, would anyone want to use mass transit?

Commuters can use the convenience of an autonomous car that provides their own private bubble, as it were, and will take them directly to where they want to go, they don’t need to wait to use it, and presumably the cost will be relatively low since there will such an abundant supply of these AI self-driving cars roaming and roving around.

Furthermore, the AI self-driving car can cover the last mile for them.

The vaunted and prized “last mile” is a reference to the problem that most mass transit options can’t get you to your actual desired destination.

Plus, some believe that there will be potentially a Personal Rapid Transit (PRT) system consisting of a means to have an autonomous car ride on a sled or similar conveyance platform, whisking the driverless in a train-like system to a destination point, and then the autonomous car will disembark and drive the rest of the way to the desired destination.

Suppose instead we say that we’ll need less mass transit, but not eliminate it entirely. There will still be circumstances perhaps of not wanting to use an AI self-driving car and instead ride on a train or a bus.

How Big Is Big

In the United States, there is about $65 billion spent annually toward the ongoing upkeep of our countries mass transit systems.

The average trip length is around 5.5 miles.

There are an estimated 433,000 people employed by mass transit in America, of which 97% of them are in the operational aspects of mass transit.

These are numbers provided by the American Public Transportation Association (APTA).

If AI self-driving cars were to emerge and if it meant that mass transit would gradually disappear or dramatically scale-down, presumably this would mean that the $65 billion annually being spent today would possibly go to other uses.

What would happen to the nearly half a million people employed by mass transit? Seemingly, hopefully, the ramp down of mass transit would occur over a lengthy enough period that those people would be able to shift to some other area of the economy.


Today, there are an estimated 5% of cars in the United States that are being used for ridesharing.

By the year 2040, some predictions are that 68% of cars will be used for ridesharing.

This opens up a tremendous capacity for doing ridesharing. It seems like this shift would have to take away ridership from someplace else, and thus mass transit could be one place that gets reduced in terms of ridership as commuters shift over to using AI self-driving cars.

As a side note, some believe that mobility today is suppressed and not fully exercised due to the arduous and costly aspects of transportation, therefore, the advent of more readily available and affordable mobility might uncork the bottle, namely unleashing the suppressed need, a phenomena often referred to as induced demand.

People today that don’t travel, or only travel to some degree N, they will all now opt to travel and do so for some heightened amount Z. If you believe in that notion, it could be that with such a massive scaling up of demand for travel, the mass transit still remains in place.

We might need both the advent of AI self-driving cars and the ongoing capability of mass transit to handle all of that gargantuan demand.

Over the last 20 years or so, the growth of mass transit passenger miles has eclipsed the number of car miles traveled (per the APTA stats). Mass transit though still only is used by a relatively small percentage of the traveling public. With the emergence and ultimately prevalence of AI self-driving cars, it might seem reasonable to anticipate that the number of car miles traveled will not only eclipse the mass transit passenger miles, but do so by perhaps a dramatic amount.

We also need to consider the opportunity costs associated with spending on future mass transit expansions.

These speculations involve all sorts of economic guesses and also technological guesses.

When will AI self-driving cars become prevalent?

Will they be as safe as mass transit?

Will they be as reliable?

Will they be more or less costly than mass transit?

Whether or not we should bet on the future of mass transit based on the various predictions is a tough call. Some say play it safe and build a potential bridge to nowhere, in case it turns out to be a bridge to somewhere, while others decry this kind of logic and say don’t put good money after bad.

Guess we need time to let this play out, and maybe a transportation “witch doctor” to sort this out.

For free podcast of this story, visit: http://ai-selfdriving-cars.libsyn.com/website

The podcasts are also available on Spotify, iTunes, iHeartRadio, etc.

More info about AI self-driving cars, see: www.ai-selfdriving-cars.guru

To follow Lance Eliot on Twitter: @LanceEliot

For his Forbes.com blog, see: https://forbes.com/sites/lanceeliot/

For his Medium blog, see: https://medium.com/@lance.eliot

For Dr. Eliot’s books, see: https://www.amazon.com/Dr.-Lance-Eliot/e/B07Q2FQ7G4

Copyright © 2019 Dr. Lance B. Eliot

Dr. Lance B. Eliot is a renowned global expert on AI, Stanford Fellow at Stanford University, was a professor at USC, headed an AI Lab, top exec at a major VC.

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