iiinova — where your digital self keeps evolving

Michael Ostrovsky @mostrovsky.bsky.social · 08/02/2025

Here is the only tip you need. You are welcome.

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Michael Ostrovsky @mostrovsky.bsky.social · 08/02/2025

You can remove "during the impending collapse of the federal government/American society" from your statement.

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Michael Ostrovsky @mostrovsky.bsky.social · 04/02/2025

Hasn’t Mirrlees already written this paper? Zero marginal tax rate at the top?

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Michael Ostrovsky @mostrovsky.bsky.social · 02/02/2025

Looking forward to reading it when you’re done!

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Michael Ostrovsky @mostrovsky.bsky.social · 02/02/2025

"You suddenly knock out a random set of the relationships (contracts) and nodes (companies) in a large and very complex network." Ooooh, exogenous random shock!

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Michael Ostrovsky @mostrovsky.bsky.social · 02/02/2025

Slides for the earliest of these papers are available at web.stanford.edu/~ost/papers/...

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Michael Ostrovsky @mostrovsky.bsky.social · 02/02/2025

Two earlier, purely theoretical papers on the topic: web.stanford.edu/~ost/papers/... web.stanford.edu/~ost/papers/...

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Michael Ostrovsky @mostrovsky.bsky.social · 02/02/2025

Shameless self-promotion: I think congestion pricing is one of the most exciting and promising topics in the near future in the area of "Engineering Societal Systems". My most recent paper on the topic is here: web.stanford.edu/~ost/papers/..., see also this thread: bsky.app/profile/most....

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Michael Ostrovsky @mostrovsky.bsky.social · 30/01/2025

NBER Market Design Working Group Report, talking about many exciting recent papers in all areas of market design/design of economic mechanisms. www.nber.org/reporter/202...

nber.org

Working Group Report: Market Design

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Michael Ostrovsky @mostrovsky.bsky.social · 25/01/2025

And how do ChatGPT/Claude do on your exams? That’s the real challenge if you do take-home exams or let students use computers.

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Michael Ostrovsky @mostrovsky.bsky.social · 15/01/2025

Prices are great and should be left alone

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Michael Ostrovsky @mostrovsky.bsky.social · 15/01/2025

(If the evidence for those CA specs is so compelling, how come our neighbors don’t adopt them?)

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Michael Ostrovsky @mostrovsky.bsky.social · 15/01/2025

Cost-benefit - I admit I don’t know much about this particular case, but if it’s good enough for the remaining 49 states, it should be fine for CA too. There is a clear, massive distortion in the market - let’s eliminate it unless the evidence for it is mega-compelling. Which I suspect it isn’t.

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Michael Ostrovsky @mostrovsky.bsky.social · 15/01/2025

I do think there must be a competition problem, but it is only there because of those extra specs which make the market much more restricted and thus easier to “coordinate” prices. More potential (or actual) entry would solve it.

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Michael Ostrovsky @mostrovsky.bsky.social · 15/01/2025

Remove those CA clean-air specs. Have the same requirements as the neighbors. Obvious first step.

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Michael Ostrovsky @mostrovsky.bsky.social · 12/01/2025

Easy fix - allow gasoline from Nevada and Oregon. Totally an own goal by CA.

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Michael Ostrovsky @mostrovsky.bsky.social · 09/01/2025

If Bill Gates was born in the Soviet Union, he would have probably ended up as a successful research mathematician or physicist.

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Michael Ostrovsky @mostrovsky.bsky.social · 09/01/2025

This rings true to me. One of the reasons why the Soviet Union was so strong in math and physics is that super-talented people in those areas didn't have nearly as many outside options to apply their talents as did comparably talented people in the United States.

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Michael Ostrovsky @mostrovsky.bsky.social · 08/01/2025

It is addressing *some* congestion (bridges and tunnels), which is not nothing. But there is more congestion to address, by charging appropriate tolls to taxis, FHVs, and delivery vehicles.

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Michael Ostrovsky @mostrovsky.bsky.social · 08/01/2025

Of course. But in this particular case, we can make useful (if still tentative) takeaways even from just three days of data. More time will generate more takeaways.

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Michael Ostrovsky @mostrovsky.bsky.social · 07/01/2025

In the paper, we work out the specific numbers, and also discuss the related issue of delivery services. Having said all this, the current plan is an amazing first step in the right direction - congratulations to all the policymakers for the incredible work they put into making this happen!

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Michael Ostrovsky @mostrovsky.bsky.social · 07/01/2025

The current plan charges a high amount per trip to regular cars, while charging little to the passengers of taxis and FHVs. So in the areas where the latter type of traffic is predominant, the plan is ineffective. Fortunately, this suggests a straightforward fix - charge more to taxis and FHVs.

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Michael Ostrovsky @mostrovsky.bsky.social · 07/01/2025

Why does this difference in composition matter, and why does it explain the difference in the effectiveness of the congestion pricing plan in the different areas (and the difference between the effects in the two screenshots)? The answer is in my paper with Frank: web.stanford.edu/~ost/papers/...

web.stanford.edu

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Michael Ostrovsky @mostrovsky.bsky.social · 07/01/2025

The second video is from an intersection within the congestion pricing zone (8th Avenue and 30th Street). Over the similar 10-minute period, the fractions of different types of vehicles are completely different: only 48 regular cars, vs. 60 TLCs and 50 taxis. www.youtube.com/watch?v=L3ha...

youtube.com

8th Avenue and 30th Street

YouTube video by Michael Ostrovsky

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Michael Ostrovsky @mostrovsky.bsky.social · 07/01/2025

Both videos are from Dec 7. First one is from Holland Tunnel exit. Over the 10 minutes, the video shows 179 regular cars, 93 TLCs, and 7 taxis (plus a bunch of cars without front plates - but that's a separate issue). So - a substantial majority of vehicles are regular cars. youtu.be/EEK6OXz3Bs4

youtu.be

Holland Tunnel

YouTube video by Michael Ostrovsky

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Michael Ostrovsky @mostrovsky.bsky.social · 07/01/2025

Frank Yang and I have hired several assistants over the past few weeks to take videos of passing cars in Manhattan and classify them (in New York, you can tell FHVs apart from regular cars by the license plates that say "TLC" on them). Below are two 10-minute videos to give a sense of differences.

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Michael Ostrovsky @mostrovsky.bsky.social · 07/01/2025

By contrast, personal vehicles are much more likely to just take two trips per entering (one trip to enter, one trip to go back home). So the routes within the congestion pricing zone have a much higher fraction of taxis/FHVs than do bridges and tunnels leading to it.

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Michael Ostrovsky @mostrovsky.bsky.social · 07/01/2025

The key difference is that Routes 1-5 are fully within the congestion pricing zone, while the bridge/tunnel routes just enter it. Why does it matter? It matters because of taxis and for-hire vehicles (FHVs - Uber and Lyft). These vehicles, by their nature, enter the area and take many trips there.

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Michael Ostrovsky @mostrovsky.bsky.social · 07/01/2025

One can again go to congestion-pricing-tracker and see similar substantial positive effects for many of the bridges and tunnels entering Manhattan (Routes 6, 7, 9, 10, 11, 12, 13) on all three days. So why is there such a striking difference?

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Michael Ostrovsky @mostrovsky.bsky.social · 07/01/2025

There is basically no effect: the red line tracks the blue one very closely. Same conclusion for all three days (Sun-Tue) on Routes 1-5 on congestion-pricing-tracker. By contrast, there is a clear and significant effect in the screenshot on the right: traffic in Holland Tunnel has improved.

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Michael Ostrovsky @mostrovsky.bsky.social · 07/01/2025

Below are two screenshots from www.congestion-pricing-tracker.com (shoutout to the amazing Joshua Moshes and Benjamin Moshes for the tool)! On the left is the time it took today to cross the congestion zone from North to South at various times of day (red line) vs. historical average (blue line).

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Michael Ostrovsky @mostrovsky.bsky.social · 07/01/2025

One would normally want to wait longer to evaluate the effects of major policy changes, but the results of the first three days of #CongestionPricing in New York City are so striking that it is already possible to make some (at least preliminary) conclusions.

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Michael Ostrovsky @mostrovsky.bsky.social · 05/01/2025

Got it. Fair point. Do it. Go for it :)

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Michael Ostrovsky @mostrovsky.bsky.social · 05/01/2025

Joke's on you - the $9 toll only applies when you *enter* Manhattan. Driving *to* Newark airport does not incur a congestion fee.

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Michael Ostrovsky @mostrovsky.bsky.social · 04/01/2025

And lifting it from the comments, here is a "plain English" writeup by Stanford Business Insights: www.gsb.stanford.edu/insights/lea...

gsb.stanford.edu

The “Least Bad” Option for Fixing New York’s Traffic Woes

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Michael Ostrovsky @mostrovsky.bsky.social · 04/01/2025

There is a recent "plain English" write-up about our paper on the Stanford GSB website that you may find interesting: www.gsb.stanford.edu/insights/lea...

gsb.stanford.edu

The “Least Bad” Option for Fixing New York’s Traffic Woes

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Michael Ostrovsky @mostrovsky.bsky.social · 04/01/2025

We plan to write a longer “plain English” op-ed sometime soon, but the basic point of the modification is that the passengers of taxis and Ubers/Lyfts need to pay a lot more per trip ($9) or per mile ($4.50) during peak time, and less (zero) during off-peak hours. Similarly for delivery services.

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Michael Ostrovsky @mostrovsky.bsky.social · 04/01/2025

Thank you, we will definitely take a look. As we discovered, reliable elasticity estimates are hard to find, so each data point is very valuable. Having said that, -.96 falls into the range of alternative elasticity values that we consider (Table 1, Section 2.4), and our main points remain valid.

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Michael Ostrovsky @mostrovsky.bsky.social · 04/01/2025

As Frank Yang and I explain in our recent paper (web.stanford.edu/~ost/papers/...), this particular version of congestion pricing is unlikely to be effective at meaningfully reducing congestion in Manhattan - but fortunately, it is fixable. So it's a great first step!

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