Wealth and Inequality

1. Branko Milanovic:

There are very good reasons to study distribution of net wealth, globally and within countries. Even for those people in the rich world who are “anomalously” placed among the wealth-poor and who may lead nice lives despite owning nothing, a shock in the form of a medical emergency (unless there is public health care), or loss of job may have catastrophic consequences. There is just no wealth to fall back on to tide you over the bad times. A decline in the value of the main asset (housing) had similar consequences for many people in the US during the recent crisis. Finally, wealth, especially when we look at the rich, is the source of both economic and political power. It is not people who are running huge, and hard to repay, credit card debts, who are likely to be “players” by contributing to the political campaigns, influencing policy and setting legislative agenda.

It was hard to excerpt. Read the whole thing. Pointer from Mark Thoma.

2. The Washington Post:

Just over a decade ago, homeownership — the single biggest engine of wealth creation for most Americans — reached a historic high for African Americans, nearly 50 percent. Now the black homeownership rate has dipped under 43 percent, and the homeownership gap separating blacks and whites is at levels not seen in a century, according to Boston University researcher Robert A. Margo.

…For a substantial number of African Americans who remain homeowners, their properties only hurt their net worth. According to the Fed survey, 1 in 7 owed more on their mortgages than their homes were worth in 2013, a sharp increase from 2010.

By comparison, just 1 in 18 white homeowners was underwater, an improvement from 2010. Also, African Americans own fewer businesses, stocks and other equities than whites — assets that have all recovered sharply since the recession.

Some of us dare to suggest that the government should encourage saving, rather than home borrowership. The housing lobby drowns us out.

Andrew Gelman is Too Glib

Not in general, but in this post, where he writes,

I’d like to flip it around and say: If we see something statistically significant (in a non-preregistered study), we can’t say much, because garden of forking paths. But if a comparison is not statistically significant, we’ve learned that the noise is too large to distinguish any signal, and that can be important.

Pointer from Mark Thoma. My thoughts:

1. Just as an aside, economists are sometimes (often?0 guilty of treating absence of evidence as evidence of absence. For example, if you fail to reject the efficient markets hypothesis, can you treat that as evidence in favor of the EMH? Many have. Similarly, when Bob Hall could not reject the random walk model of consumer spending, he said that this was evidence in favor of rational expectations and consumption smoothing.

2. I think that a simpler way to make Gelman’s point would be to say that passing a statistical significance test is a necessary but not a sufficient condition for declaring the evidence to be persuasive. In particular, one must also address the “selection bias” problem, which is that results that pass significance tests are more likely to be written up and published than results that fail to do so.

What’s In Alexis Tsipras’ Wallet?

He is soon to be the Greek premier. The Independent reports,

A Syriza government would have to rely on taxes but tax revenues are down as people wait to see if taxes will be reduced by the new government. This means that Greece may only have the money – though this is disputed by Syriza leaders – until the end of February to pay state employees and pensions and service the debt.

As a far leftist, we can presume he wants to spend lots of other people’s money. Where can he get it?

1. Greek taxpayers. Greece actually was supposed to run a primary surplus this year, meaning that they would only have to borrow to pay interest on debt, not to fund ordinary spending. But apparently the Greek taxpayers do not see it that way. UPDATE: Tony Yates points out a problem even if you have a primary surplus and decide to blow off the interest on your debt. (pointer from Mark Thoma),

the Greek government does not have the funds to stand behind its own banks. They would be left insolvent by a Greek default [economically, they are already, really]. A run on Greek banks, either prompted by default or the threat of it, could not be stemmed by a credible guarantee of deposits.

2. Non-bank investors willing to invest in Greek bonds. Considering that Tsipras does not sound particularly eager to pay off such investors, they might be a bit shy.

3. Banks willing to invest in Greek bonds, since those bonds carry zero risk (according to capital regulations). Still, I can imagine that bank managers are a tad worried that the regulators who designated sovereign debt as risk-free don’t actually have any money with which to back that up.

4. The European Central Bank, which just announced a big “quantitative easing” program, so it needs stuff to buy. The question is how eager Germany and other European countries are to be Tsipras’ sugar daddies.

Pointers in (1) and (4) from Tyler Cowen. Possible outcomes, in order from highest probability to lowest:

1. Eurocrats devise a new elaborate shell game under which they funnel money from other countries to Tsipras while pretending not to do so, hoping that ordinary voters in those countries will not notice, or that even if people notice they will be powerless to do anything about it.

2. The European central bank goes ahead and buys bonds from Tsipras, because the alternative is scarier.

3. Tsipras ends up implementing austerity, because his wallet is empty.

4. Tsipras ends up printing a new Greek currency, as Greece exits the Euro.

Michael Shermer Scrambles the Axes

You can listen to his talk at Cato.

In some respects, he sounds conservative. He seems to me to take a civilization vs. barbarism view of recent controversies regarding police, in that he believes that in a civilized society citizens must not threaten police. He insists that moral significance attaches to people as individuals, not as members of oppressed classes.

However, he breaks with conservatives in that he views religion as barbaric. He insists instead on science and reason. And in general, I think he would be happier earning the approval of progressives than earning that of conservatives. His main theme, that human beings are making moral progress (he speaks of a moral Flynn Effect), is one that sits more easily with progressives than with conservatives.

To the extent that he is libertarian, he sounds more like Rand than like Rothbard. He believes that the institution of the state is needed to keep individuals from using violence to solve disputes.

On economic issues, he offered thumbs-up for free trade and economic growth. But he said nothing about what I see as the most fundamental issue in economic philosophy today: how much can the emergent order of a little-regulated economy be improved by technocratic management? Clearly there are those who think that the answer is very much, while there are those of us who disagree. I suspect that Shermer is not on the libertarian side of this issue.

Bob Hall on Labor Force Participation Trends

With Nicolas Petrosky-Nadaeu, he writes (scroll down at the link for the paper),

In the bottom 10 percent of households by household income, 33 percent of individuals participated in the labor market in 1998-1999. By 2011-2013 this proportion was 44 percent. At the other end of the household income distribution, the rate of labor market participation fell from 81 to 76 percent. The largest decline was for individuals living in households in the third quartile of the household income distribution, where the participation rate fell from 74 percent to 68 percent.

Pointer from Tyler Cowen.

Usually, I would have possible explanations handy. In this case, I am so stumped that I am willing to offer the possibility that their statistics are not accurate.

UPDATE: Possibly relevant:

According to a recent Pew report, the percentage of mothers who stay at home with their children (a statistic that includes non-working single mothers) fell from 49% in the late 1960s to a low of 23% in 1999, but then rose to 29% by 2012.

The Omniscient Voyeur

Bryan Caplan writes,

In the GSS, males report an average of 14.19, women an average of 4.76.* If you mean the median, then males report a median of 3, woman a median of 2.

In my statistics course, I use this as a classic example of biased statistics. Here is why I suspect bias.

Suppose that the number of men is M and the number of women is W. Suppose that an omniscient voyeur can count all of the heterosexual relationships. Call this number n. Then the average number of sex partners for men is n/M. For women, it is n/W. Assuming that W and M are about the same, then the omniscient voyeur will know that the averages are about the same. So if the reported averages are different, then the reported averages are biased statistics.

What I am Reading

1. Michael Shermer, The Moral Arc. I am only a few pages in, and he already has cited Bill Dickens and Bryan Caplan, among others.

2. Jeffrey Friedman and Wladimir Kraus, Engineering the Financial Crisis. This is a re-read for me. They share with me the view that risk-based capital rules contributed heavily to the crisis. They make a very subtle point, though. They do not believe that bankers went all-out to maximize the effective leverage of their banks. Thus, the authors reject the moral hazard arguments of deposit insurance and too-big-to-fail.

The way I would put their argument is this. Suppose that bank managers were, for whatever reason, actually quite concerned about risk exposure. They thought, even if incorrectly, that the value of keeping their franchises intact and avoiding trouble was very important. Even so, with the risk weights that regulators placed on different assets, the effective rate of return on mortgage securities was much higher than that on other asset classes, including low-risk mortgage loans. Thus, the risk-based capital rules, along with the lenient ratings by rating agencies of mortgage securities, served to steer capital into high-risk mortgage loans and thereby into feeding the housing bubble.

In making their argument that the crisis was in my terminology a cognitive failure rather than a moral failure, the authors point out that if bankers had merely wanted to maximize their exploitation of implicit and explicit guarantees, they could have acted differently. They could have held higher-risk, higher-return tranches of mortgage securities. They could have held less capital (before the crisis, major banks tended to have leverage ratios well below regulatory limits).

Heritability of g

Plomin and Deary write,

(i) The heritability of intelligence increases from about 20% in infancy to perhaps 80% in later adulthood. (ii) Intelligence captures genetic effects on diverse cognitive and learning abilities, which correlate phenotypically about 0.30 on average but correlate genetically about 0.60 or higher. (iii) Assortative mating is greater for intelligence (spouse correlations ~0.40) than for other behavioural traits such as personality and psychopathology (~0.10) or physical traits such as height and weight (~0.20). Assortative mating pumps additive genetic variance into the population every generation, contributing to the high narrow heritability (additive genetic variance) of intelligence.

Pointer from Kyle Griffin. Read the whole thing. The authors’ discussion of Genome-wide Complex Trait Analysis, a new method of examining genetic influence, was new to me. Deary is the author of Intelligence: A Very Short Introduction, which doubles as an excellent introduction to statistical methods in research.

In my appearance in St. Louis in six weeks, I will be talking about the forces that cause stratification of earnings to accelerate. One of those factors is assortative mating based on g.

Taleb, Evolution, and GMOs

The podcast with Russ Roberts is here.

Taleb’s point is that “science” cannot prove that GMO’s are safe. We know that when organisms evolve using a trial-and-error process of gradual tweaking, that process is safe. But direct intervention to create GMO’s is not the same process.

Taleb says.

The big risk is what can happen when you have two things going together–which is, what happens, Soviet style, is a combination of monopoly of some plants over others, that it’s too large a system; and of course creation of other species that will themselves also be too powerful and then you may kill the GMOs or one may kill the other and you may have huge imbalances in nature. And these imbalances in nature can produce large deviations.

I think I get Taleb’s point. But it strikes me that to cause catastrophic harm, a GMO has to be both weird enough to cause unprecedented things to happen but not so weird that it fails to function as a living organism. That may be an impossible combination.