A flaw regarding the chance of “out-earning” your parents

When Raj Chetty publishes a paper, it generally comes with a splash. The last one is no exception. His paper (co-authored), picked up by David Leonhardt at the New York Times and Justin Wolfers on Twitter, basically measures the American dream : what are your chances to do better than your parents. The stunning conclusion is that someone born in 1940 had a 90%+ chance of “out-earning” his parents compared with a few points above 50% for those born in the 1980s. I am not convinced. Well, when I am not convinced, I am saying I am not convincing about how big the drop is! I think the drop is smoother (the slope of decline is gentler) and the starting point for the 1940 cohort is too high.  As a big fan of Chetty, I must press this point.

More precisely, I am saying that the bar (income threshold) over which someone had to jump in 1940 is underestimated and overestimated in 1980. Setting the bar too low (high) means very high (low) chances of “out-earning” your parents. To set the bar too low, you must underestimate (overestimate) the income of the parents.  This could occur if household economies of scale are not accounted for.

An income of 30,000$ for 3 persons is not the same as an income of 60,000$ for 6 peoples. On a per capita basis, the income is the same. But, if you adjust for economies of scale in housing and furnitures, there are differences (the simplest is square root).  This gives you income per adult equivalent. Chetty et al. are aware of that and they provided a sensitivity analysis which is not mentioned by those who are relaying the article. Since household size has tended to fall over time, the growth in per capita income is faster than the growth in income per adult equivalent (a better measure). Any correction for this long-term demographic trend would attenuate the slope of the decline of the chance to out-earn your parents. And indeed, once Chetty et al. make the correction, the decline is much more modest (but still present – see below).


Simultaneously, Chetty et al. also present other important sensitivity checks. All of them relevant. But, in a strange decision, Chetty et al. decided to isolate each of the sensitivity checks rather than compile them. Taken individual, they all seem minor – except adjusting for family size. But compound this with the other sensitivity check proposed by Chetty et al.: price deflators. Using the well-known bias in the the CPI that overestimates inflation by 0.8%, Chetty et al. find that, by the end of their perod, there is roughly a ten percentage point difference between the baseline uncorrected CPI and the corrected CPI (see below). Compound this with the corrections for family and you still get a decline – but again the slope of the decline is much more modest. If you add panel B from figure 3 in Chetty et al – which includes taxes and transfers – you probably get a few extra points up. There will still probably be a decline, but a moderate one.


Finally, at footnote 19, Chetty et al. also point out that they do not account for in-kind transfers prior to 1967 (there were some).  And, on page 13, they point out that “one may be concerned that levels of absolute mobility for recent cohorts may still be understated because of increases in fringe benefits, nonmarket goods, or under-reporting of income in the CPS”. Add in all these little extra problems to the family size, the transfers and the inflation correction and I am not sure how big the drop from 1940 to the end of the studied period is. Finally, I would also add that an understudied point in economic history is what the distribution of in-kind payments according to income was. From studying the British industrial revolution, I have generally to see that it is the poorest workers who receive in-kind payments (which are not measured) and the richest receive much fewer of those in proportion of their incomes. One of the few to note that distributional was the hardcore left-leaning scholar Gabriel Kolko who mentioned this issue in Dissent back in the 1950s.  If Kolko is correct, then the income of “poor parents” in 1940 is underestimated. As a result, the bar over which the children of said parents must jump is set mildly too low. If that is the case, the odds for the 1940 birth cohort are overestimated.

Combine all of these things together and I am not sure that the drop is as dramatic as many are making it out to be. I would be very satisfied if Chetty et al. would publish all the corrections they did and do a sensitivity check with hypothetical regarding a sliding-scale of in-kind payments in 1940 according to income (10% of income for poorest to 0% for the richest). I would just like to see how much it matters.

In Cuba, not having a car might save your life

My two blog posts on the health statistics of Cuba have convinced me to try to assemble a research article on the topic of assessing health outcomes under Castro’s regime. My first blog post was that there is a trade-off (the core of the article) that Castro decided to make. He would use extreme coercive measures to reduce some forms of mortality in order to shore up support abroad. The cost of such institutions is limited economic growth and increased mortality from other causes (dying from waterborne diseases or poverty diseases rather than dying from measles).

When I thought of that, I was inspired by Werner Troesken’s Pox of Liberty on the American constitution and the disease environment of the country. I was mostly concerned by direct medical interventions. However, the extent of coercive measures used by Castro go well beyond simple medical care (or medical imposition). Price controls, rationing and import restrictions on many goods could also help improve life expectancy. Indeed, rationing salt at 10g (hypothetical number) per person per day is a good way to prevent dietary diseases that emerge as a complication from overconsumption of salt. That will, by definition, raise life expectancy.

And so will bans on importing cars.

There is an extensive literature on the role that car fatalities has on life expectancy. This paper in Demography (one of the top demographic journals) finds that male life expectancy in Brazil is lowered by 0.8 years by traffic deaths. And traffic has very little to do with the quality of health care services. Basically, the more you drive, the more chances you have of dying (duh!). But, people don’t care much because the benefits of driving outweigh the personal risks.

In Cuba, people don’t get to make that choice. As a result, the very few drivers on Cuban roads have few accidents. According to WHO data, the car fatality rate is 8.15 per 100,000. There is also only 55 cars per 1,000 persons in Cuba. The next closest country is Nicaragua at 93 cars per 1,000 and the top country is Uruguay at 584 cars per 1,000. When you compute reported (rather than WHO estimated) car fatalities per 1,000 cars (rather than persons), Cuba becomes the unsafest place to drive in Latin America (1.46 fatalities per 1,000 cars) after El Salvador (2.22 fatalities per 1000 cars but only 129 cars per 1000), Ecuador (1.78 fatalities per 1000 cars but only 109 cars per 1000) and Bolivia (1.53  fatalities per 1000 cars and only 113 cars per 1000).

The graph below shows the relation between car fatalities per 100,000 inhabitants and life expectancy. Cuba is singled out as a black square. Low rate of car fatalities, higher life expectancy. Obviously, this is not a regression and so I am not trying to infer too much. However, it seems fair to say that Cuba’s life expectancy can easily be explained by the fact that Cubans face stiff prohibitions on the ability to drive. Those prohibitions give them a few extra years of life for sure, but would you really call that a ringing endorsement of the health outcomes under Castro’s regime? I don’t…


Regional jealousies and transboundary rivers in South Asia

In the final reckoning, Pakistan got about 80 per cent of the Indus and India 20 per cent. India has limited rights on the western rivers and cannot undertake projects on those rivers without providing all the details to Pakistan and dealing with Pakistan’s objections. Why did India put itself in that position? The answer is that if Pakistan got the near-exclusive allocation of the three western rivers, India for its part got the eastern rivers. This was important from the point of view of the Indian negotiators because the water needs of Punjab and Rajasthan weighed heavily with them in seeking an adequate allocation of Indus water for India. Yet, Punjab had a serious grievance over the signing of the IWT [Indus Waters Treaty] by the union government. Citing provisions of the IWT which caused transfer of three river waters to Pakistan, Punjab had terminated all its water-sharing agreements with its neighbouring states in 2004.

The demand of Kutch (in Indian Gujarat), which used to fall into a catchment area of River Indus, decades back, was not taken into consideration despite many petitions, arguing about their historical claim on its water, sent by the prominent Kutchi leaders, in 1950s, to India’s Ministry of Irrigation and Power. Also people from the Indian side of Kashmir always show their ire against the IWT. On 3 April 2002, the Jammu & Kashmir Legislative Assembly, cutting across party affiliations, called for a review of the treaty. The state government has been contending that in spite of untapped hydroelectric potential, the state has been suffering from acute power deficiency due to restrictions put on the use of its rivers by the Indus Treaty. They claim that their interests were not taken into consideration and their views were not taken while signing the treaty. (6-7)

This is from my latest paper, “Disputed Waters: India, Pakistan and the Transboundary Rivers,” published by Studies in Indian Politics, and which you can find here.

Here is a map of all the Indian states mentioned in the excerpt above:



Testing the High-Wage Economy (HWE) Hypothesis

Over the last week or so, I have been heavily involved in a twitterminar (yes, I am coining that portemanteau term to designate academic discussions on twitter – proof that some good can come out of social media) between myself, Judy Stephenson , Ben Schneider , Benjamin Guilbert, Mark Koyama, Pseudoerasmus,  Anton Howes (whose main flaw is that he is from King’s College London while I am from the LSE – nothing rational here), Alan Fernihough and  Lyman Stone. The topic? How suitable is the “high-wage economy” (HWE) explanation of the British industrial revolution (BIR).

Twitter debates are hard to follow and there is a need for summaries given the format of twitter. As a result, I am attempting such a summary here which is laced with my own comments regarding my skepticism and possible resolution venues.

An honest account of HWE

First of all, it is necessary to offer a proper enunciation of HWE’s role in explaining the industrial revolution as advanced by its main proponent, Robert Allen.  This is a necessary step because there is a literature attempting to use high-wages as an efficiency wage argument. A good example is Morris Altman’s Economic Growth and the High-Wage Economy  (see here too) Altman summarizes his “key message” as the idea that “improving the material well-being of workers, even prior to immediate increases in productivity can be expected to have positive effects on productivity through its impact on economic efficiency and technological change”. He also made the same argument with my native home province of Quebec relative to Ontario during the late 19th century. This is basically a multiple equilibria story. And its not exactly what Allen advances. Allen’s argument is that wages were high in England relative to energy. This factors price ratio stimulated the development of technologies and industries that spearheaded the BIR. This is basically a context-specific argument and not a “conventional” efficiency wage approach as that of Allen. There are similarities, but they are also considerable differences. Secondly, the HWE hypothesis is basically a meta-argument about the Industrial Revolution. It would be unfair to caricature it as an “overarching” explanation. Rather, the version of HWE advanced by Robert Allen (see his book here) is one where there are many factors at play but there is one – HWE – which had the strongest effects. Moreover, while it does not explain all, it was dependent on other factors that contributed independently.  The most common view is that this is mixed with Joel Mokyr’s supply of inventions story (which is what Nick Crafts has done). In the graph below, the “realistically multi-causal” explanation is how I see HWE. In Allen’s explanation, it holds the place that cause #1 does. According to other economists, HWE holds spot #2 or spot #3 and Mokyr’s explanations holds spot #1.


In pure theoretical terms (as an axiomatic statement), the Allen model is defensible. It is a logically consistent construct. It has some questionnable assumptions, but it has no self-contradictions. Basically, any criticism of HWE must question the validity of the theory based on empirical evidence (see my argument with Graham Brownlow here) regarding the necessary conditions. This is the hallmark of Allen’s work: logical consistency. His work cannot be simply brushed aside – it is well argued and there is supportive evidence. The logical construction of his argument requires a deep discussion and any criticism that will convince must encompass many factors.

Why not France? Or How to Test HWE

As a doubter of Allen’s theory (I am willing to be convinced, hence my categorization as doubter), the best way to phrase my criticism is to ask the mirror of his question. Rather than asking “Why was the Industrial Revolution British”, I ask “Why Wasn’t it French”. This is what Allen does in his work when he asks explicitly “Why not France?” (p.203 of his book). The answer proposed is that English wages were high enough to justify the adoption of labor-saving technologies. In France, they were not. This led to differing rates of technological adoptions, an example of which is the spinning jenny.

This argument hinges on some key conditions :

  1. Wages were higher in England than in France
  2. Unit labor costs were higher in England than in France (productivity-adjusted wages) (a point made by Kelly, Mokyr and Ó Gráda)
  3. Market size factors are not sufficiently important to overshadow the effects of lower wages in France (R&D costs over market size mean a low fixed cost relative to potential market size)
  4. The work year is equal in France as in England
  5. The cost of energy in France relative to labor is higher than in England
  6. Output remained constant while hours fell – a contention at odds with the Industrious Revolution which the same as saying that marginal productivity moves inversely with working hours

If most of these empirical statements hold, then the argument of Allen holds. I am pretty convinced by the evidence advanced by Allen (and E.A. Wrigley also) regarding the low relative of energy in England. Thus, I am pretty convinced that condition #5 holds. Moreover, given the increases in transport productivity within England (here and here), the limited barriers to internal trade (here), I would not be surprised that it was relatively easy to supply energy on the British market prior to 1800 (at least relative to France).

Condition #3 is harder to assess in terms of important. Market size, in a Smithian world, is not only about population (see scale effects literature). Market size is a function of transaction costs between individuals, a large share of which are determined by institutional arrangements. France has a much larger population than England so there could have been scale effects, but France also had more barriers to internal trade that could have limited market size. I will return to this below.

Condition #1,2,4 are basically empirical statements. They are also the main points of tactical assault on Allen’s theory.  I think condition #1 is the easiest to tackle. I am currently writing a piece derived from my dissertation showing that – at least with regards to Strasbourg – wages in France presented in Allen (his 2001 article) are heavily underestimated (by somewhere between 12% and 40% using winter workers in agriculture and as much as 70% using the average for laborers in agriculture). The work of Judy Stephenson, Jane Humphries and Jacob Weisdorf has also thrown the level and trend of British wages into doubts. Bringing French wages upwards and British wages downwards could damage the Allen story. However, this would not be a sufficient theory. Industrialization was generally concentrated geographically. If labor markets in one country are not sufficiently integrated and the industrializing area (lets say the “textile” area of Lancashire or the French Manchester of Mulhouse or the Caën region in Normandy) has uniquely different wages, then Allen’s theory can hold since what matters is the local wage rate relative to energy. Pseudoerasmus has made this point but I can’t find any mention of that very plausible defense in Allen’s work.

Condition #2 is the weakest point and given Robert Fogel’s work on net nutrition in France and England, I have no problem in assuming that French workers were less productive. However, the best evidence would be to extract piece rates in textile-producing regions of France and England. This would eliminate any issue with wages and measuring national productivity differences. Piece rates would perfectly capture productivity and thus the argument could be measured in a very straightforward manner.

Condition #4 is harder to assess and more research would be needed. However, it is the most crucial piece of evidence required to settle the issue once and for all. Pre-industrial labor markets are not exactly like those of modern days. Search costs were high which works in a manner described (with reservations) by Alan Manning in his work on monopsony but with much more frictions. In such a market, workers may be willing to trade in lower wage rates for longer work years. In fact, its like a job security argument. Would you prefer 313 days of work guaranteed at 1 shilling per day or a 10% chance of working 313 days for 1.5 shillings a day (I’ve skewed the hypothetical numbers to make my point)? Now, if there are differences in the structure of labor markets in France and England during the 18th and 19th centuries, there might be differences in the extent of that trade-off in both countries. Different average discount on wages would affect production methods. If French workers were prone to sacrifice more on wages for steady employment, it may render one production method more profitable than in England. Assessing the extent of the discount of annual to daily wages on both markets would identify this issue.

The remaining condition (condition #6) is, in my opinion, dead on arrival. Allen’s model, in the case of the spinning jenny, assumed that labor hours moved in an opposite direction as marginal productivity. This is in direct opposition to the well-established industrious revolution. This point has been made convincingly by Gragnolati, Moschella and Pugliese in the Journal of Economic History. 

In terms of research strategy, getting piece rates, proper wage estimates and proper labor supplied estimates for England and France would resolve most of the issue. Condition #3 could then be assessed as a plausibility residual.  Once we know about working hours, actual productivity and real wages differences, we can test how big the difference in market size has to be to deter adoption in France. If the difference seems implausible (given the empirical limitations of measuring effective market size in the 18th century in both markets), then we can assess the presence of this condition.

My counter-argument : social networks and diffusion

For the sake of argument, let’s imagine that all of the evidence favors the skeptics, then what? It is all well and good to tear down the edifice but we are left with a gaping hole and everything starts again. It would be great to propose a new edifice as the old one is being questioned. This is where I am very much enclined towards the rarely discussed work of Leonard Dudley (Mothers of Innovation). Simply put, Dudley’s argument is that social networks allowed the diffusion of technologies within England that fostered economic growth. He has an analogy from physics which gets the point across nicely. Matter has three states : solid, gas, liquid. Solids are stable but resist to change. Gas, matter are much more random and change frequently by interacting with other gas, but any relation is ephemeral. Liquids permit change through interaction, but they are stable enough to allow interactions to persist for some time. Technological innovation is like a liquid. It can “mix” things together in a somewhat stable form.

This is where one of my argument takes life. In a small article for Economic Affairs, I argued (expanding on Dudley) that social networks allowed this mixing (I am also expanding that argument in a working paper with Adam Martin of Texas Tech University). However, I added a twist to that argument which I imported from the work of Israel Kirzner (one of the most cited books in economics, but not by cliometricians – more than 7000 citations on google scholar). Economic growth, in Kirzner’s mind,  is the result of entrepreneurs discovering errors and arbitrage possibilities. In a way, growth is a process of discovering correcting errors. An analogy to make this point is that entrepreneurs look for profits where the light is while also trying to move the light to see where it is dark. What Kirzner dubs as “alertness” is in fact nothing else than repeated and frequent interactions. The more your interact with others, the easier it becomes for ideas to have sex. Thus, what matters is how easy it is for social networks to appear and generate cheap information and interactions for members without the problem of free riders. This is where the work of Anton Howes becomes very valuable. Howes, in his PhD thesis supervised by Adam Martin who is my co-author on the aforementioned project (summary here), showed that most innovators went in frequent with one another and they inspired themselves from each other. This is alertness ignited!

If properly harnessed, the combination of the works of Howes and Dudley (and also James Dowey who was a PhD student at the LSE with me and whose work is *Trump voice* Amazing) can stand as a substitute to Allen’s HWE if invalidated.


If I came across as bashing on Allen in this post, then you have misread me. I admire Allen for the clarity of his reasoning and his expositions (given that I am working on a funded project to recalculate tax-based measures in the US used by Piketty to account for tax avoidance, I can appreciate the clarity in which Allen expresses himself). I also admire him for wanting to “Go big or go home” (which you can see in all his other work, especially on enclosures). My point is that I am willing to be convinced of HWE, but I find that the evidence leans towards rejecting it. But that is very limited and flawed evidence and asserting this clearly is hard (as some of the flaws can go his way). Nitpicking Allen’s HWE is a necessary step for clearly determining the cause of BIR. It is not sufficient as a logically consistent substitute must be presented to the research community. In any case, there is my long summary of the twitteminar (officially trademarked now!)

P.S. Inspired by Peter Bent’s INET research webinar on institutional responses to financial crises, I am trying to organize a similar (low-cost) venue for presenting research papers on HWE assessment. More news on this later.

Carta de Voltaire dirigida a Rousseau, em resposta a ele

Um excelente texto mostrando o contraste entre dois conceitos de liberdade. Voltaire representa a liberdade do liberalismo clássico: o indivíduo deve ser livre de constrangimentos externos, ser livre para buscar sua concepção individual de felicidade. Rousseau representa outra concepção de liberdade: o indivíduo só será livre se acatar um conceito de felicidade que os demais irão lhe impor. Rousseau está por trás de basicamente todas a ditaduras estabelecidas desde então, principalmente as de esquerda, formadas por pessoas de bem que sabem o que é bom para os outros, que falam que o capitalismo só cria problemas e que deveríamos fazer um governo mais “democrático”. Em outras palavras, pessoas chatas, agressivas, que não respeitam as decisões alheias e sentem uma incontrolável vontade de ensinar para os outros o que é bom.

30 de Agosto de 1755

Recebi, senhor, vosso novo livro contra o gênero humano, e vos agradeço por isso. Vós agradareis aos homens, sobre quem fala vossas verdades, e não os emendará. Ninguém poderia pintar um quadro com cores mais fortes dos horrores da sociedade humana, para os quais nossa ignorância e debilidade tem tanta esperança de consolo. Ninguém jamais empregou tanta vivacidade em nos tornar novamente animais: pode-se querer andar com quatro patas, quando lemos vossa obra. Entretanto, como já faz mais de sessenta anos que perdi este costume, percebo, infelizmente, que é impossível recomeçar, e deixo essa maneira natural àqueles que são mais dignos que vós e eu. Já não posso mais embarcar para encontrar os selvagens do Canadá, em primeiro lugar, porque as doenças de que sofro me prendem ao redor do maior médico da Europa, e não encontraria a mesma assistência junto aos Missouris. Em segundo, porque a guerra está sendo travada lá naquele país, e o exemplo de nossas nações tornou os selvagens quase tão perigosos quanto nós. Devo me limitar a ser um selvagem pacífico, na solidão que escolhi, perto de vossa pátria, onde vós devíeis estar.

Concordo convosco que a literatura e as ciências causaram ocasionalmente muitos danos. Os inimigos de Tasso fizeram de sua vida uma longa série de infortúnios. Os de Galileu fizeram-no gemer dentro da prisão, aos setenta anos de idade, por haver entendido como a Terra se movimenta; e o que é ainda mais desonroso, obrigaram-no a desdizer-se. Desde que vossos amigos começaram a publicar o Dicionário Enciclopédico, os rivais os desafiam com o tratamento de deístas, ateus e mesmo de jansenistas.

Se porventura eu puder me incluir entre aqueles cujos trabalhos não trouxeram mais do que a perseguição como única recompensa, poderei mostrar-vos o tipo de gente perseguidora que me prejudica desde que produzi minha tragédia Édipo; uma biblioteca de calúnias ridículas impressas contra mim. Um ex-padre jesuíta, que salvei da desgraça total, me pagou o serviço que lhe prestei com um libelo difamatório; um homem, ainda mais culpado, imprimiu minha própria obra sobre o século de Luís XIV com notas nas quais a mais crassa ignorância vomitou as mais baixas imposturas; um outro, que vendeu a um editor, usando meu nome, alguns capítulos de uma pretensa História Universal; o editor, ávido o suficiente para imprimir esse amontoado de erros crassos, datas erradas, fatos e nomes mutilados; e, finalmente, os homens covardes e vis o suficiente para me responsabilizar pela publicação desta rapsódia. Eu mostrar-vos-ei a sociedade contaminada por este tipo de homens – desconhecido em toda a antiguidade – que, não podendo abraçar uma profissão honesta, seja de trabalho manual ou de serviço, e desafortunadamente sabendo ler e escrever, se tornam agentes literários, vivem de nossas obras, roubam os manuscritos, alteram-nos, vendem-nos. Eu poderia lamentar-me porque fragmentos de uma zombaria, feitos há pelo menos trinta anos, sobre o mesmo sujeito que Chapelain foi burro o bastante para tratar seriamente, circulam hoje pelo mundo, graças à traição e avareza desses infelizes, que misturaram suas grosserias às minhas pilhérias, e preencheram as lacunas com uma estupidez equiparada somente à sua malícia e que, ao cabo de 30 anos, vendem por toda parte um manuscrito que é apenas deles, e digno tão somente deles.

Eu poderia acrescentar, em último lugar, que roubaram uma parte do material que eu juntei nos arquivos públicos para usar na História da Guerra de 1741, quando era historiador da França; que venderam a uma livraria de Paris esse fruto de meu trabalho; que nessa época invejaram minhas posses, como se eu estivesse morto e pudessem colocá-las à venda. Eu poderia mostrar a ingratidão, a impostura e o roubo me perseguindo por quarenta anos, do pé dos Alpes ao pé do meu túmulo. Mas o que eu concluiria de todos esses tormentos? Que não tenho o direito de reclamar; que o Papa, Descartes, Bayle, Camões e centenas de outros sofreram injustiças iguais, ou ainda maiores; que este destino é o de quase todos daqueles que foram inteiramente seduzidos pelo amor às letras.

Admita, senhor, que estas coisas são pequenas desgraças particulares de que a sociedade pouco se apercebe. Que importa para a humanidade que alguns zangões roubem o mel de poucas abelhas? Os homens das letras fazem grande estardalhaço de todas estas pequenas querelas, enquanto o resto do mundo ou os ignora ou disso gargalha.

De todos os desgostos afetando a vida humana, esses são os menos graves. Os espinhos ligados à literatura, ou um pouco menos de reputação, são flores quando comparados aos outros males que a todo momento inundam a terra. Admita que Cícero, Varrão, Lucrécio ou Virgílio não tiveram a menor culpa nas proscrições. Mário era um ignorante, Sila, um bárbaro, Antônio, um crápula, o imbecil Lépido leu um pouco de Platão e Sófocles; enquanto Otávio César, covardemente apelidado de Augusto, esse tirano sem coragem, agiu apenas como um assassino detestável no momento em que privou a sociedade dos homens de letras.

Admita que Petrarca e Boccaccio não fizeram nascer os problemas da Itália; que as brincadeiras de Marot não produziram São Bartolomeu, e que a tragédia de Cid não produziu a guerra da Fronde. Os grandes crimes são cometidos apenas pelos grandes ignorantes. O que faz e fará sempre deste mundo um vale de lágrimas é a avidez e o indomável orgulho dos homens, desde Thamas-Kouli-Kan, que não sabia nem ler, até um oficial de alfândega, que não sabe nem contar. As letras alimentam, endireitam e consolam a alma; elas vos servem, senhor, durante o tempo que escreveis contra elas. Vós sois como Aquiles, que se encolerizava contra a glória, e como o padre Malebranche, que, com sua imaginação brilhante, escrevia contra a imaginação.

Se alguém tem o direito de queixar-se da literatura, sou eu, porque em todos os momentos e em todos os lugares ela serviu à minha perseguição; mas deve-se amá-la, não obstante o mau uso que dela fazem; como deve-se amar a sociedade na qual tantos homens maldosos corrompem os suscetíveis; como deve-se amar a sua pátria, mesmo que ela nos trate com alguma injustiça; como se deve amar o Ser Supremo, apesar das superstições e do fanatismo que desonram tão freqüentemente o seu culto.

M. Chappuis disse-me que vossa saúde anda muito mal, deveis restabelecê-la na terra natal, aproveitando junto à sua liberdade, beber comigo o leite de nossas vacas, e passear em seus campos.

Muito filosoficamente e com a mais alta estima, etc

The Uniqueness of Italian Internal Divergence

A few weeks ago, I got engaged in a twitter debate with Garett Jones, Pseudoerasmus and Anna Missiaia (see her great work here) about institutions in Italy. During the course of that discussion, I was made aware that I held a false belief. Namely, the belief that since the late 19th century, there had only been a minor divergence within Italy. In reality, there has been considerable divergence within the country since the late 19th century.

In the wake of the Italian referendum, it is worth examining how big is this divergence. Below is a map of regional GDP per capita taken from Europa.ec.  The southern regions of Italy have GDP per capita below 75% of the European average while some of the northern regions have GDP per capita above 125% of the European average. The IStat database suggest similar levels of divergence across regions in Italy.


So, how much divergence was there – say a little a more than one hundred years ago? Well, according to the great work of Felice (see here in the Economic History Review and here), there were more similarities back in the 19th century than there are today. Take the Liguria which – in 1891 – had per capita value added of 44% above national average. Take also Campania which was 3% below the national average. Today, the IStat data places Liguria 9% above national average but the region of Campania is 37% below the national average. Overall, regardless of how you present the data , divergence has increase. Just expressed at coefficient of variations, there has been an increase. In 1891, the coefficient of variation stood at 22.95% while it stood at 28.95% in 2013.


This makes Italy into an oddity. My own work shows that in Canada, since the 19th century, there has been considerable convergence (see article in Economics Bulletin). The same happened in the United States (see this paper by Michener and McLean), in England (here and here) and in Sweden (here). Among western countries, increased internal divergence is rare and Italy is the prime case example. And this is a strong indictment. Either Italy as a whole shares the same steady-state status and something is preventing upwards convergence from the South or Italy has two different economies with two different steady-states. In both cases, the implications are depressing.

Has there been any improvements in the relative economic conditions of American blacks?

A few years ago, I was teaching at HEC Montréal and I explained that putting people in prison – by statistical definition – did reduce unemployment. My students were shocked that I would say that. I told them that it was important to know definitions like that because you can then analyze the BS that politicians and pundits can spew.

And the case of Black-Americans is the best example, especially with regards to the wage gap. In recent years, I have seen pundits (left and right) use the slightly increasing ratio of black-to-white wages as a tool to promote their favored political narrative (i.e. the BS that I am referring to).

But, at the same time, the incarceration rates of Blacks has increased dramatically. Tell me, do you think that the socio-economic features of blacks in jail are distributed the same way as the socio-economic features of blacks not in jail? Of course not, criminals tend to be clustered disproportionately at the bottom of the income ladder. However, when its time to collect the wage statistics for blacks and whites, you are basically considering only the wages of blacks not in jail (i.e. blacks who are in the top centiles of the wage distribution). So, you’re basically committing a sin of statistical composition.

Some bloggers have caught on to that – the wage ratio is going up at the same pace as the incarceration rate for blacks. But they caught on after the work of scholars like Becky Pettit and Bruce Western came along (here and here and see graph below that illustrates the effect of correcting for incarceration on the employment rate of blacks).


When I look at this evidence, I understand why some people are pissed off at the conditions of Black Americans. It throws in doubt the contention that there has been racial convergence in America. At the same time, I wonder if the lack of recognition given to this statistical issue is a form of cognitive dissonance. If you claim that the convergence is mostly an artifice of composition fallacies, then what does it say about the policies of the last 30-40 years?