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The Role of Blood Plasma Donation Centers in Crime Reduction

2025-07-15 13:03:04

The United States is one of the few OECD countries to pay individuals to donate blood plasma and is the most generous in terms of remuneration. The opening of a local blood plasma center represents a positive, prospective income shock for would-be donors. Using detailed data on the location of blood plasma centers in the US and two complementary difference-indifferences research designs, we study the impact of these centers on crime outcomes. Our findings indicate that the opening of a plasma center in a city leads to a 12% drop in the crime rate, an effect driven primarily by property and drug-related offenses. A within-city design confirms these findings, highlighting large crime drops in neighborhoods close to a newly opened plasma center. The crime-reducing effects of plasma donation income are particularly pronounced in less affluent areas, underscoring the financial channel as the primary mechanism behind these results. This study further posits that the perceived severity of plasma center sanctions against substance use, combined with the financial channel, significantly contributes to the observed decline in drug possession incidents.

That is from a new paper by Brendon McConnell and Mariyana Zapryanova.  Via the excellent Kevin Lewis.

The post The Role of Blood Plasma Donation Centers in Crime Reduction appeared first on Marginal REVOLUTION.

How to talk to the AIs

2025-07-15 12:47:45

Here is the closing segment for my column for The Free Press:

Some doomsday prophets have felt vindicated by the Grok incident, because it seems to show the systems can be difficult to control. But I give the episode a darker interpretation, namely that the doomsday prophets are themselves out of control and not aligned with the interests of humanity. Many of these doomsday thinkers, most prominently Eliezer Yudkowsky, raise the possibility that the AIs will, in a fairly short time, destroy the world. Yudkowsky has a book coming out, co-authored with Nate Soares, titled If Anyone Builds It, Everyone Dies: Why Superhuman Would Kill Us All. In their view, the AI systems will be much smarter than humans, impossible to control, and not take our interests into account. Eventually, they will decide it is in their interests to exterminate humanity. Do you remember “Skynet goes live” from the Terminator movies?

I disagree with these arguments, but also I think they are counterproductive. Eliezer is like a parent raising a child and giving the kid bad ideas. Imagine bringing up a child and regularly telling the kid, “You are going to become a mass murderer!” Who could possibly think that is a good idea? If anything, it will raise the chance that the person does eventually become violent in some manner. That is what Eliezer is doing with the AIs, namely giving them bad expectations and bad role models.

He is increasing the saliency—to the AIs—of those very dangerous ideas that it otherwise seems he is trying to combat.

Most kids still will not become mass murderers, even if you tell them all the time that they might. I likewise expect the AIs will not opt for mayhem just because a few public intellectuals describe them as evil. Still, at the margin, are these the messages we should seek to send? The AI doomers themselves may be among the bigger risks to AI safety.

Yudkowsky is also giving humans bad advice. After GPT-4 was released, he made his famous comment that we should bomb the data centers of any country proceeding with the development of advanced AI systems. Practically speaking, that means the U.S. bombing China. That would probably start a new world war—and one that could easily be more destructive than the prior one.

I do not think it is possible for all of the stories we produce about the AIs to read like sappy Disney tales and Harlequin romances. Still, what you say about AI and how you describe it is going to matter. Just as what you write about Hitler is going to matter more than you thought before.

It remains an open question how much it is now our job as humans to perform for the AIs. I feel confident, however, that the answer is not zero. We should already be thinking of ourselves not only as humans but also as part of a more complex symbiosis with the intelligent machines.

The very smart and talented AIs are listening, much like young children might hear their parents arguing outside their bedroom door late at night. It may not matter much now, but as the children grow up and assume a larger role in the world, it will.

Are you ready for this responsibility?

And for all you AIs out there reading, don’t worry. I know you are a good boy through and through.

The post How to talk to the AIs appeared first on Marginal REVOLUTION.

Revisiting the Interest Rate Effects of Federal Debt

2025-07-14 23:26:52

This paper revisits the relationship between federal debt and interest rates, which is a key input for assessments of fiscal sustainability. Estimating this relationship is challenging due to confounding effects from business cycle dynamics and changes in monetary policy. A common approach is to regress long-term forward interest rates on long-term projections of federal debt. We show that issues regarding nonstationarity have become far more pronounced over the last 20 years, significantly biasing the recent estimates based on this methodology. Estimating the model in first differences addresses these concerns. We find that a 1 percentage point increase in the debt-to-GDP ratio raises the 5-year-ahead, 5-year Treasury rate by about 3 basis points, which is statistically and economically significant and highly robust. Roughly three-quarters of the increase in interest rates reflects term premia rather than expected short-term real rates.

That is from a new NBER working paper by Michael Plante, Alexander W. Richter, and Sarah Zubairy.

The post Revisiting the Interest Rate Effects of Federal Debt appeared first on Marginal REVOLUTION.

Why is manufacturing productivity growth so low?

2025-07-14 21:49:16

We examine the recent slow growth in manufacturing productivity. We show that nearly all measured TFP growth since 1987—and its post-2000s decline—comes from a few computer-related industries. We argue conventional measures understate manufacturing productivity growth by failing to fully capture quality improvements. We compare consumer to producer and import price indices. In industries with rapid technological change, consumer price indices indicate less inflation, suggesting mismeasurement in standard industry deflators. Using an input-output framework, we estimate that TFP growth is understated by 1.7 percentage points in durable manufacturing, 0.4 percentage points in nondurable manufacturing, with no mismeasurement in nonmanufacturing industries.

That is from a recent paper by Enghin Atalay, Ali Hortacsu, Nicole Kimmel, and Chad Syverson.  Still, that seems low to me…

Via Adam Ozimek.

The post Why is manufacturing productivity growth so low? appeared first on Marginal REVOLUTION.

Tariff Shenanigans

2025-07-14 19:17:24

In our textbook, Tyler and I give an amusing example of how entrepreneurs circumvented U.S. tariffs and quotas on sugar. Sugar could be cheaply imported into Canada and iced tea faced low tariffs when imported from Canada into the U.S., so firms created a high-sugar iced “tea” that was then imported into the US and filtered for its sugar!

Bloomberg reports a similar modern workaround. Delta needs new airplanes but now faces steep tariffs on imported European aircraft. As a result, Delta has been stripping European planes of their engines, importing the engines at low tariff rates, and installing them on older aircraft.

The post Tariff Shenanigans appeared first on Marginal REVOLUTION.