nobel

Fellow EWED blogger Jeremy Horpedahl generally gives good advice. Therefore, when the other week he provided a link and recommended that we watch Joel Mokyr’s 2025 Nobel lecture*, I did so.

There were three speakers on that linked YouTube, who were the economics laureates for this year. They received the prize for their work on innovation-driven economic growth. The whole video is nearly two hours long, which is longer than most folks want to listen to, unless they are on a long car trip. Joel’s talk was the first, and it was truly engaging.

For time-pressed readers here, I have snipped many of the speakers’ slides, and pasted them below, with minimal commentary.

First, here are the great men themselves:

Talk # 1. Joel Mokyr: Can Progress in Innovation Be Sustained?

And indeed, one can find pieces of evidence that point in this direction, such as the slower pace of pharm discoveries.

But Joel is optimistic:

Joel provides various examples of advances in theoretical knowledge and in practical technology (especially in making instruments) feeding each other. E.g., nineteenth century advances in high resolution microscopy led to study of micro-organisms which led to germ theory of disease, which was one of the all-time key discoveries that helped mankind:

So, on the technical and intellectual side, Joel feels that the drivers are still in place for continued strong progress. What may block progress are unhelpful human attitudes and fragmentation, including outright wars.

Or, as Friedrich Schiller wrote, “Against stupidity, the gods themselves contend in vain”.

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Talk # 2: Philippe Aghion, The Economics of Creative Destruction

He commented that on the personal level, what seems to be a failure in your life can prove to be “a revival, your savior” (English is not his first language; but the point is a good one).

Much of his talk discussed some inherent contradictions in the innovation process, especially how once a new firm achieves dominance through innovation, it tends to block out newer entrants:

KEY SLIDE:

Outline of the rest of his talk:

[ There were more charts on fine points of his competition/innovation model(s)]

Slide on companies’ failure rate, grouped by age of the firm:

His comment..if you are a young , small firm, it only takes one act of (competitors’) creative destruction to oust you, whereas for older, larger, more diverse firms, it might take two or three creative destructions to wipe you out.

He then uses some of these concepts to address “Historical enigmas”

First, secular stagnation:

[My comment: Total factor productivity (TFP) growth rate in economics measures the portion of output growth not explained by increases in traditional inputs like labor and capital. It is often considered the primary contributor to GDP growth, reflecting gains from technological progress, efficiency improvements, and other factors that enhance production]

I think this chart was for the US. Productivity, which grew fast in the 1996-2005 timeframe, then slowed back down.

In the time of growth soaring, there was increased concentration in services. The boost in ~1993-2003 was a composition effect, as big techs like Microsoft, Amazon, bought out small firms, and grew the most. But then this discouraged new entries.

Gap is increasing between leaders and laggers, likely due to quasi-monopoly of big tech firms.

Another historical enigma – why do some countries stop growing? “Middle Income Trap”

Made a case for Korea, Japan growing fastest when they were catching up with Western technology, then slowed down.

China for past 30 years has been growing by catching up, absorbing outside technology. But the policies for pioneering new technologies are different than those for catching up.

Europe: During WWII lot of capital was destroyed, but they quickly started to catch up with US (Europe had good education, and Marshall plan rebuilt capital)…but then stagnated, because not as strong in innovation.

Europeans are doing mid-tech incremental innovation, whereas US is doing high tech breakthrough.

[my comment: I don’t know if innovation is the whole story, it is tough to compete with a large, unified nation sitting on so much premium farmland and oil fields]

Patents:

Red =US, blue=China, yellow=Japan, green=Europe. His point: Europe is lagging.

Europe needs true unified market, policies to foster innovation (and creative destruction, rather than preservation).

Finally: Rethinking Capitalism

GINI index is a measure of inequality.

Death of unskilled middle-aged men in U.S.…due in part to distress over of losing good jobs [I’m not sure that is the whole story]. Key point of two slides above is that US has more innovation, but some bad social outcomes.

So, you’d like to have best of both…flexibility (like US) AND inclusivity (like Europe).

Example: with Danish welfare policies, there is little stress if you lose your job (slide above).

Found that innovation (in Europe? Finland?) correlated with parents’ income and education level:

…but that is considered suboptimal, since you want every young person, no matter parents’ status, to have the chance to contribute to innovation. Pointed to reforms of education in Finland, that gave universal access to good education..claimed positive effects on innovation.

Final subtopic: competition. Again, the mega tech firms discourage competition. It used to be that small firms were the main engine of job growth, now not so much:

Makes the case that entrant competition enhances social mobility.

Conclusions:

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Talk # 3. Peter Howitt

The third speaker, Peter Howitt showed only a very few slides, all of which were pretty unengaging, such as:

So, I don’t have much to show from him. He has been a close collaborator of Philippe Aghion, and he seemed to be saying similar things. I can report that he is basically optimistic about the future.

* The economics prize is not a classic “Nobel prize” like the ones established by the Swedish dynamite inventor himself, but was established in 1968 by the Swedish national bank “In Memory of Alfred Nobel.”

Here is an AI summary of the 2025 economics prize:

The 2025 Sveriges Riksbank Prize in Economic Sciences in Memory of Alfred Nobel was awarded to Joel Mokyr, Philippe Aghion, and Peter Howitt for their groundbreaking work on innovation-driven economic growth. Mokyr received half of the prize for identifying the prerequisites for sustained growth through technological progress, emphasizing the importance of “useful knowledge,” mechanical competence, and institutions conducive to innovation. The other half was jointly awarded to Aghion and Howitt for developing a mathematical model of sustained growth through “creative destruction,” a concept that explains how new technologies and products replace older ones, driving economic advancement. Their research highlights that economic growth is not guaranteed and requires supportive policies, open markets, and mechanisms to manage the disruptive effects of innovation, such as job displacement and firm failures. The award comes at a critical time, as concerns grow over threats to scientific research funding and the potential for de-globalization to hinder innovation.

Today marks the 27^th anniversary of John Nash winning The Sveriges Riksbank Prize in Economic Sciences in Memory of Alfred Nobel for his contributions to game theory.

Opinions on game theory differ. To most of the public, it’s probably behind a shroud of mystery. To another set of the specialists, it is a natural offshoot of economics. And, finally a 3^rd non-exclusive set find it silly and largely useless for real-world applications.

Regardless of the camp to which you claim membership, the Pure Strategy Nash Equilibrium (PSNE) is often misunderstood by students. In short, the PSNE is the set of all player strategy combinations that would cause no player to want to engage in a different strategy. In lay terms, it’s the list of possible choices people can make and find no benefit to changing their mind.

In class, I emphasize to my students that a Nash Equilibrium assumes that a player can control only their own actions and not those of the other players. It takes the opposing player strategies as ‘given’.

This seems simple enough. But students often implicitly suppose that a PSNE does more legwork than it can do. Below is an example of an extensive form game that illustrates a common point of student confusion. There are 2 players who play sequentially. The meaning of the letters is unimportant. If it helps, imagine that you’re playing Mortal Kombat and that Player 1 can jump or crouch. Depending on which he chooses, Player 2 will choose uppercut, block, approach, or distance. Each of the numbers that are listed at the bottom reflect the payoffs for each player that occur with each strategy combination.

Again, a PSNE is any combination of player strategies from which no player wants to deviate, given the strategies of the other players.

Students will often proceed with the following logic:

Player 2 would choose B over U because 3>2.
Player 2 would choose A over D because 4>1.
Player 1 is faced with earning 4 if he chooses J and 3 if he chooses C. So, the PSNE is that player 1 would choose J.
Therefore, the PSNE set of strategies is (J,B).

While students are entirely reasonable in their thinking, what they are doing is not finding a PSNE. First of all, (J,B) doesn’t include all of the possible strategies – it omits the entire right side of the game. How can Player 1 know whether he should change his mind if he doesn’t know what Player 2 is doing? Bottom line: A PSNE requires that *all* strategy combinations are listed.

The mistaken student says ‘Fine’ and writes that the PSNE strategies are (J, BA) and that the payoff is (4,3)*. And it is true that they have found a PSNE. When asked why, they’ll often reiterate their logic that I enumerate above. But, their answer is woefully incomplete. In the logic above, they only identify what Player 2 would choose on the right side of the tree when Player 1 chose C. They entirely neglected whether Player 2 would be willing to choose A or D when Player 1 chooses J. Yes, it is true that neither Player 1 nor Player 2 wants to deviate from (J, BA). But it is also true that neither player wants to deviate from (J, BD). In either case the payoff is (4, 3).

This is where students get upset. “Why would Player 2 be willing to choose D?! That’s irrational. They’d never do that!” But the student is mistaken. Player 2 is willing to choose D – just not when Player 1 chooses C. In other words, Player 2 is indifferent to A or D so long as Player 1 chooses J. In order for each player to decide whether they’d want to deviate strategies given what the other player is doing, we need to identify what the other player is doing! The bottom line: A PSNE requires that neither player wants to deviate given what the other player is doing – Not what the other player would do if one did choose to deviate.

What about when Player 1 chooses C? Then, Player 2 would choose A because 4 is a better payoff than 1. Player 2 doesn’t care whether he chooses U or B because (C, UA) and (C, BA) both provide him the same payoff of 4. We might be tempted to believe that both are PSNE. But they’re not! It’s correct that Player 2 wouldn’t deviate from (C, BA) to become better off. But we must also consider Player 1. Given (C, UA), Player 1 won’t switch to J because his payoff would be 1 rather than 3. Given (C, BA), Player 1 would absolutely deviate from C to J in order to earn 4 rather than 3. So, (C, UA) is a PSNE and (C, BA) is not. The bottom line: Both players must have no incentive to deviate strategies in a PSNE.

There are reasons that game theory as a discipline developed beyond the idea of Nash Equilibria and Pure Strategy Nash Equilibria. Simple PSNE identify possible equilibria, but don’t narrow it down from there. PSNE are strong in that they identify the possible equilibria and firmly exclude several other possible strategy combinations and outcomes. But PSNE are weak insofar as they identify equilibria that may not be particularly likely or believable. With PSNE alone, we are left with an uneasy feeling that we are identifying too many possible strategies that we don’t quite think are relevant to real life.

These features motivated the later development of Subgame Perfect Nash Equilibria (SGPNE). Students have a good intuition that something feels not quite right about PSNE. Students anticipate SGPNE as a concept that they think is better at predicting reality. But, in so doing, they try to mistakenly attribute too much to PSNE. They want it to tell them which strategies the players would choose. They’re frustrated that it only tells them when players won’t change their mind.

Regardless of whether you get frustrated by game theory, be sure to have a drink and make toast to John Nash.

*Below is the normal form for anyone who is interested.