2021: Our Most Popular Posts

While the blog got its start with Joy Buchanan in mid-2020, we are now just finishing up our first full year and now have a full weekly slate of bloggers. This seems like a good opportunity to reflect on our most popular posts from each of our regular bloggers. We hope you enjoy looking back at these popular posts.

Monday: Mike Makowsky

Makowsky‘s most popular post was from May 2021, titled “Academic Publishing: How I think we got here.” This post generated a significant amount of discussion on Twitter among economists and other academics, and is the second most widely read post on this blog with almost 10,000 views. Makowsky outlined the history and incentives of “how we got here” in terms of the problems with academic publishing, and he is skeptical that there is any easy fix. It seems there is nothing economists love arguing about more than our profession itself. (Follow Makowsky on Twitter)

Tuesday: Scott Buchanan

Scott Buchanan‘s most popular post is “Money as a Social Construct” is from September 2020. It discusses the very basic definition of what we mean by money, and the importance of social trust for both the functioning of money and general social order. The related theme of cryptocurrencies is something he has written a lot about in the last few months of 2020. (He is not yet on Twitter!)

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PSNE: No More, No Less

Today marks the 27th 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, is a natural offshoot of economics. And, finally a 3rd 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:

  1. Player 2 would choose B over U because 3>2.
  2. Player 2 would choose A over D because 4>1.
  3. 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.
  4. 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) does 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 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 identified 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.

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 not 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.

Redesigning Unemployment Insurance

How does unemployment insurance work?

From the worker’s perspective, unemployment insurance isn’t detectable unless the worker loses their job. Once that’s happened, the person can apply for benefits – a check that you can cash or deposit into your bank account. These benefits vary by state, with the composition of your family, and your income prior to separation. The most generous maximum benefit is provided by Massachusetts at $823 per week for an individual and the least generous is provided by Mississippi at $235 per week. States also vary by the length of time for which a person can collect benefits. Montana is the most generous at 28 weeks and North Carolina ties with Florida for the least generous at 12 weeks. If you find a job and become employed before the maximum benefit duration, then you stop receiving payments.

From the employer’s perspective, unemployment insurance is the premium that you pay per employee each year. The premium is not optional – so it’s a tax. Employers pay it for the privilege employing workers. There are two components of the tax: a state and federal portion. The federal portion is more or less constant per employee. The state portion changes with the incidence of unemployment claims and payments that a state makes in the prior year. When a lot of people get fired, state unemployment taxes rise as a policy response.

Why provide UI benefits?

There are two typical reasons for governments to provide unemployment benefits – and a 3rd not-so-typical reason. The first is as a matter of relief. People often lose a job through no fault of their own, and we don’t want those people to become destitute or to forego the bare essentials that money can afford. The second reason to provide benefits is as a matter of macroeconomic spending stimulus. Contrary to popular belief, this stimulus is not about encouraging greater production through greater sales. The stimulus is meant to encourage total spending in the economy to be higher than it would have been otherwise (See Irving Fisher on debt deflation and Scott Sumner on NGDP targeting). The 3rd and not so typical reason for governments to provide unemployment insurance is to keep people from going to work (See Tyler Cowen for why this might be desirable during a pandemic).

Incentives Matter

The 3rd reason above hints at a problem. People lose benefits when they become employed again. It is exactly because benefits provide relief that they reduce the incentive to find a job. Importantly, this is not a judgment of propriety or moral chastisement. It simply is the case that UI payments make being unemployed a little more tolerable. The tenacity with which people search for a job becomes a little less urgent. Anyone well acquainted with human nature (outside of a textbook) will tell you that it is good for humans to work. There are economic, social, and psychological benefits – not to mention the material benefits enjoyed by society. So, longer periods of unemployment are a problem.

Not only does the receiving UI benefits cause longer unemployment spells, losing benefits when you find a job acts as a penalty to finding a labor market match. It’s not happenstance that people who lose their UI benefits tend to become employed shortly thereafter. In terms of economic activity and gains from trade, society is materially better off when people find jobs more quickly (probably socially better off too). If you can get people to acknowledge the above logic, then there is plenty of room for people to disagree on the propriety of the UI benefits system.

Remove Disincentives – Keep the Relief

As Thomas Sowell is known for saying “There are no solutions – only trade-offs.”  That’s true. It’s also true that there is also no such thing as a free lunch. But some things are a lot more like a free lunch than others.

Wouldn’t it be nice if we could just help unemployed people and not disincentivize them from finding a job? In part it’s impossible. The UI payments do both and there is no separating them. But, the disincentive provided by removing payments when a job is found can be addressed. Why not just permit UI benefits even after someone has found a job?

An Outlay Neutral Prescription

What does the social program designer consider? Simply, the policy maker considers government outlays, government revenues, and economic impact. All else constant, policy makers like small outlays, high revenues, and good economic impacts.

I propose that states adopt the following policy. First, eliminate variables benefits. This part of the policy is not essential, but it clarifies the exposition. Now, it doesn’t matter whether you were an executive at a bank or a janitor at the bank – both receive the same weekly UI payment if they lose their job. What should the benefit be? For the purposes of outlay neutrality, the new benefit is the same as the average benefit was last year. The average benefit and total outlay across all claimants is unchanged.

When a person finds a job under the current system they are paying an implicit tax when their benefits get pulled. Let’s eliminate the employment disqualification. That’s right. When a person finds a job, they just continue to receive benefits. They don’t receive UI benefits indefinitely, however. In order to maintain outlay neutrality, the duration of UI benefit payments will be equal to the average duration last year.

Say what?!

Put yourself in the shoes of the person looking for a job under the current system. Say that your UI benefit is $800 per week and that you job-search for 10 hours each week. Say that you find a job that pays $1,000 per week. If you take the job, then you will go from working 10 hours per week to working 40 hours per week. And, you go from having an income of $800 per week to having an income of $1,000 per week. In other words, you get to work 30 more hours per week for $200 more income. The unemployed person is making the decision to take the job at $25 per hour, or stay home at $80 per hour ($1,000/40 Vs $800/10).

But what’s the perspective under the outlay neutral proposal in which the benefits continue even after employment? The decision is substantially different.  The unemployed person is making the decision to take the job at an average of $45 per hour, or stay home at $80 per hour ($1,800/40 Vs $800/10).

Of course, staying home still might look attractive. But it looks relatively less attractive than it did under the standard system of work-disqualifying benefits. If a person has 4 weeks of remaining benefits when they find the job, then continuing to receive UI benefits would mean that the total income over that month would be $7,200, versus $3,200 from staying home, or $4,000 under the standard system. Again putting yourself in the shoes of the unemployed, doesn’t this decision look different? Might you feel enticed to accept the job?

Under the proposed policy, government outlays are constant – there is no change in expenditures. Revenues increase because more employed workers means more employer-paid UI tax payments (not to mention other tax payments). Economic performance improves because greater employment increases total output. Let’s go ahead and throw in the additional social benefits too.

People Have Feelings

…And they’re complicated. Part of the sympathetic idea of unemployment insurance benefits is to provide relief. As a matter of gut instinct, this is why many people favor the UI transfer program over others. They can imagine themselves in such a circumstance through no wrong-doing of their own. But once we say that benefits will continue – even after someone finds their job – the UI program becomes less obviously a matter of sympathy-inducing relief. There is a political problem.

I say: put your feelings aside. Let’s get people employed again. Let’s increase tax revenues and increase economic activity. Let’s address the problem of unemployment in a better way – and spend not a dime more doing it.

Wait for the Lower Cost Version of Policy

I’ve written previously about initial US state compulsory schooling laws in regard to literacy and in school attendance rates. I ended with a political economy hypothesis. Here’s the logic:

  1. Legislators like lower costs, all else constant (more funding is available for other priorities).
  2. Enforcing truancy and educating an illiterate populous is costly.
  3. Therefore, state legislatures that passed compulsory attendance legislation will already have had relatively high rates of school attendance and literacy.

That’s it. Standard political economy incentives. But is it true? Well, we can’t tell what’s going on in politician heads today, much less 150 years ago. Though, we can observe evidence that might corroborate the story. In plain terms, consistent evidence for the hypothesis would be that school attendance and literacy rates were rising prior to compulsory schooling legislation. The figures below show attendance and literacy rates for children ages 10 to 18.

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