There is no ignorance so blind as academic ignorance.

Interesting: Exaggeration, lack of perspective or simple ignorance? I enjoy the Literary Review principally because their reviewers are informed and are more experienced in the real world than most academic reviewers. But sometimes examples of delusional mindsets creep in. This is from Trading Places, a review by Andrea Stuart of Coolie Woman: The Odyssey of Indenture by Gaiutra Bahadur. The topic of the book is an interesting one and not often discussed - the intra-imperial migrations of the British Empire. Not just white colonialists out from the Metropolitan to the colonies but all sorts of intra-imperial migrations to Fiji, Guyana, Trinidad & Tobago, South Africa, etc. Bahadur's family was part of those migrations, moving from India to Guyana sometime around 1900 (not clear in the review when).

Here is the sentence that leapt out to me. I am surprised it did not get caught in the editing process.

In 1987 they fled the troubled realities of British Guiana, still haunted by its slave past, and moved to New Jersey. There the new migrants would find the conditions almost as hostile as those that their ancestors had once encountered elsewhere in the New World.

Really? You are comparing conditions of a free immigrant in 1987 New Jersey to those of an indentured migrant in 1900 Guyana?

What were the harsh conditions in New Jersey? Local residents protested the arrival of new immigrants in their community. Someone spat on her father. One of the immigrants was beaten up. Obviously that shouldn't happen. But do you honestly think that is the equivalent of indentured servitude in Guyana in 1900? And if you don't, why say so?

Curious about who could make such a blindingly stupid comment, I looked up Andrea Stuart's bio at the front of the magazine.

Andrea Stuart is currently a Writer in Residence at Kingston University.

Enough said. There is no ignorance so blind as academic ignorance.

Everything is subject to change over time

From Two Cheers for 'First World Problems' by Virginia Postrel.

In a world of constraints, necessary trade-offs, constantly changing circumstances and ever changing expectations, it is a challenge to maintain philosophical and emotional harmony. Postrel has some excellent discussion of the tension between rising expectations and maintaining a sense of perspective.

Online shopping and overnight shipping have become like Google or IMDB. They constitute what what my strategy-professor husband Steven Postrel calls “new-wave utilities,” a category that also includes ubiquitous retailers such as 7-Eleven and Starbucks. These businesses have taught us to count on them -- and take them for granted -- the way we assume the tap water will be clean and the lights will turn on. Unless something goes wrong, we don’t think about how amazing they are or how we got them in the first place.

It took years of sustained efforts by online retailers and delivery services to make overnight orders realistic. It also took dissatisfaction: insanely demanding companies working to please insanely demanding customers -- or, in some cases, to offer customers services they hadn’t even thought to ask for -- as each improvement revealed new sources of discontent.

“Form follows failure,” is what Henry Petroski, the civil engineering professor and prolific popular writer, calls the process. Every step forward begins with a complaint about what already exists. “This principle governs all invention, innovation, and ingenuity; it is what drives all inventors, innovators, and engineers,” he writes. “And there follows a corollary: Since nothing is perfect, and, indeed, since even our ideas of perfection are not static, everything is subject to change over time.”

Rising expectations aren’t a sign of immature “entitlement.” They’re a sign of progress -- and the wellspring of future advances. The same ridiculous discontent that says Starbucks ought to offer vegan pumpkin lattes created Starbucks in the first place. Two centuries of refusing to be satisfied produced the long series of innovations that turned hunger from a near-universal human condition into a “third world problem.”

Complaining about small annoyances can be demoralizing and obnoxious, but demanding complacency is worse. The trick is to simultaneously remember how much life has improved while acknowledging how it could be better. In the new year, then, may all your worries be first world problems.

Of particular relevance, we found evidence for a strong coupling over time between cognitive abilities . . . and reading

Well this is an interesting summary that I have never seen anywhere. I love reading and am convinced that there is a beneficial relationship between enthusiastic reading and cognitive capability. However, I have never seen any studies that empirically support that assumption. But apparently I have been looking in the wrong places. This summary from Uncoupling of Reading and IQ Over Time: Empirical Evidence for a Definition of Dyslexia by Emilio Ferrer, Bennett A. Shaywitz, John M. Holahan, Karen Marchione, and Sally E. Shaywitz is pretty categorical.

In previous research (Ferrer & McArdle, 2004), we found a strong association between the development of cognitive ability and changes in academic achievement (i.e., academic knowledge and quantitative abilities) during childhood and
adolescence. We described these interconnections as coupled developmental sequences in which levels of one variable were
positively related to changes in time in the other variable. Of particular relevance, we found evidence for a strong coupling over time between cognitive abilities (i.e., Full Scale, Nonverbal, and Verbal IQ on the Wechsler Intelligence Scale for Children–Revised, or WISC-R) and reading (i.e., Letter-Word Identification, Word Attack, and Passage comprehension reading scales from the Woodcock-Johnson Psycho-Educational Battery, or WJ) for individuals in Grades 1 to 12 (Ferrer et al., 2007). Such couplings represented influences from, for example, cognition in a given year to positive changes in reading the following year. Results from those analyses indicated that (a) there was a positive dynamic relation between reading and cognitive ability from Grades 1 to 12; (b) this dynamic relation was symbiotic, with each process influencing the other over time; and (c) the mutual dynamics of reading and cognition appeared to be strongest during Grades 1 to 3, less strong during 4th to 8th grade, and weakest from 9th to 12th grade. Studies of adults, too, have found that cognitive ability (Verbal IQ) predicts reading accuracy (Berninger, Abbott, Thomson, & Raskind, 2001).

I am reading this to say that reading and IQ are reinforcing and that the biggest impact is in the earliest years.

There is also this from Diet, Parental Behavior, and Preschool Can Boost Children’s IQ by Anna Mikulak.

Interventions focused on interactive reading — teaching parents how to engage their children while reading with them — were found to raise children’s IQ by over 6 points. These interventions do not seem to have an effect for children over 4 years old, suggesting that the interventions may accelerate language development, which, in turn, boosts IQ.

I sometimes wish that people would put a little more emphasis on the observance of the law than they do on its enforcement.

It is always dangerous to stray into Wikiquotes. There is so much that is so interesting.

Dangerous as it might be, I periodically wander over to check the source of a quote to ensure that proper attribution is being made accurately. I was just looking up a quote by Calvin Coolidge and came across all these other worthies.

It is characteristic of the unlearned that they are forever proposing something which is old, and because it has recently come to their own attention, supposing it to be new.

From 'Address at Holy Cross' (25 June 1919), published in Have Faith In Massachusetts: A Collection of Speeches and Messages (2nd Ed.), Coolidge, Houghton Mifflin, p. 231

Workmen’s compensation, hours and conditions of labor are cold consolations, if there be no employment.

From the speech ‘Plymouth, Labor Day’ (1 September 1919), as printed in Have Faith in Massachusetts: A Collection of Speeches and Messages (2nd Ed.), Houghton Mifflin, pp. 200-201

I favor the policy of economy, not because I wish to save money, but because I wish to save people. The men and women of this country who toil are the ones who bear the cost of the Government. Every dollar that we carelessly waste means that their life will be so much the more meager. Every dollar that we prudently save means that their life will be so much the more abundant. Economy is idealism in its most practical form.

Coolidge's Inaugural Address (1924).

Governments do not make ideals, but ideals make governments. This is both historically and logically true. Of course the government can help to sustain ideals and can create institutions through which they can be the better observed, but their source by their very nature is in the people. The people have to bear their own responsibilities. There is no method by which that burden can be shifted to the government. It is not the enactment, but the observance of laws, that creates the character of a nation.

"Speech on the Occasion of the 150th Anniversary of the Declaration of Independence" (5 July 1926).

There is far more danger of harm than there is hope of good in any radical changes.

"Speech on the Occasion of the 150th Anniversary of the Declaration of Independence" (5 July 1926).

We live in an age of science and abounding accumulation of material things. These did not create the Declaration. Our Declaration created them. The things of the spirit come first. Unless we cling to that, all of our material prosperity, overwhelming though it may appear, will turn to a barren scepter in our grasp. If we are to maintain the great heritage bequeathed to us, we must be like minded as the Founders who created. We must not sink into a pagan materialism. We must cultivate the reverence which they had and for the things that are holy. We must follow the spiritual and moral leadership which they showed. We must keep replenished, that they may glow with a more compelling flame, the altar fires before which they worshipped.

"Speech on the Occasion of the 150th Anniversary of the Declaration of Independence" (5 July 1926).

Mr. Hoover, if you see ten troubles coming down the road, you can be sure that nine will run into the ditch before they reach you and you have to battle with only one of them.

As recounted by Herbert Hoover ; from Coolidge: An American Enigma, Robert Sobel, Regnery Publishing (2000), p. 242 : ISBN 0895262479, 9780895262479

I sometimes wish that people would put a little more emphasis on the observance of the law than they do on its enforcement. It is a maxim of our institutions, that the government does not make the people, but the people make the government.

From an address before the Women’s National Committee for Law Enforcement, as quoted in The New England historical and genealogical register, Volume 87, H. F. Waters, New England Historic & Genealogical Society (1933), p. 100

Nothing in the world can take the place of persistence. Talent will not; nothing is more common than unsuccessful men with talent. Genius will not; unrewarded genius is almost a proverb. Education will not; the world is full of educated derelicts. Persistence and determination alone are omnipotent. The slogan "press on" has solved and always will solve the problems of the human race.

Quote from a program at a Coolidge memorial service (1933); cited in The Oxford Dictionary of Quotations (1999).

Current needs versus past luxuries

From Calvin Coolidge.

Workmen’s compensation, hours and conditions of labor are cold consolations, if there be no employment.

From the speech ‘Plymouth, Labor Day’ (1 September 1919), as printed in Have Faith in Massachusetts: A Collection of Speeches and Messages (2nd Ed.), Houghton Mifflin, pp. 200-201

A great example of the importance of priorities. All the above are good things but the ability to be productively employed necessarily takes precedence over the necessary safeguards associated with that employment.

Too often we hold the nice-to-haves as sacrosanct over the need-to-haves. All nations move in cycles of prosperity and either retrenchment or restructuring. The great challenge, during those phases of restructuring and retrenchment, is balancing the needs of the future against the privileges of the past.

We see this playing out across the nation as municipalities approach or plunge into bankruptcy. Which takes precedence in Detroit, the benefit and pension obligations incurred when the city was 2 million strong and growing at 5% or the restructuring and smaller cost structures necessary for a city of 700,000, shrinking by 5% a year and needing to relaunch itself? Historically we have answered that old obligations take precedence but obviously the right answer is current needs over past nice-to-have obligations.

Obvious it might be but its unpleasantness prompts us to hide from the harsh decisions that follow from such prioritization.

All the glorious realms owned by happy credulity in days of yore

From the preface to the tale The Adalantado of the Seven Cities by Washintgon Irving. Just simply beautiful evocation of imagination and wonder.

"There are more things in heaven and earth than are dreamed of in our philosophy," and among these may be placed that marvel and mystery of the seas, the Island of St. Brandan. Those who have read the history of the Canaries, the fortunate islands of the ancients, may remember the wonders told of this enigmatical island. Occasionally it would be visible from their shores, stretching away in the clear bright west, to all appearance substantial like themselves, and still more beautiful. Expeditions would launch forth from the Canaries to explore this land of promise. For a time its sungilt peaks and long, shadowy promontories would remain distinctly visible, but in proportion as the voyagers approached, peak and promontory would gradually fade away until nothing would remain but blue sky above and deep blue water below. Hence this mysterious isle was stigmatized by ancient cosmographers with the name of Aprositus or the Inaccessible. The failure of numerous expeditions sent in quest of it, both in ancient and modern days, has at length caused its very existence to be called in question, and it has been rashly pronounced a mere optical illusion, like the Fata Morgana of the Straits of Messina, or has been classed with those unsubstantial regions known to mariners as Cape Fly Away and the coast of Cloud Land.

Let us not permit, however, the doubts of worldly-wise sceptics to rob us of all the glorious realms owned by happy credulity in days of yore. Be assured, O reader of easy faith! - thou for whom it is my delight to labor - be assured that such an island actually exists, and has from time to time been revealed to the gaze and trodden by the feet of favored mortals. Historians and philosophers may have their doubts, but its existence has been fully attested by that inspired race, the poets ; who, being gifted with a kind of second sight, are enabled to discern those mysteries of nature hidden from the eyes of ordinary men. To this gifted race it has ever been a kind of wonder-land. Here once bloomed, and perhaps still blooms, the famous garden of the Hesperides, with its golden fruit. Here, too, the sorceress Armida had her enchanted garden, in which she held the Christian paladin, Rinaldo, in delicious but inglorious thraldom, as set forth in the immortal lay of Tasso. It was in this island that Sycorax the witch held sway, when the good Prospero and his infant daughter Miranda were wafted to its shores. Who does not know the tale as told in the magic page of Shakespeare? The isle was then

". . . full of noises,
Sounds, and sweet airs, that give delight, and hurt
not."

The island, in fact, at different times, has been under the sway of different powers, genii of earth, and air, and ocean, who have made it their shadowy abode. Hither have retired many classic but broken-down deities, shorn of almost all their attributes, but who once ruled the poetic world. Here Neptune and Amphitrite hold a diminished court, sovereigns in exile. Their ocean-chariot, almost a wreck, lies bottom upward in some sea-beaten cavern ; their pursy Tritons and haggard Nereids bask listlessly like seals about the rocks. Sometimes those deities assume, it is said, a shadow of their ancient pomp, and glide in state about a summer sea ; and then, as some tall Indiaman lies becalmed with idly flapping sail, her drowsy crew may hear the mellow note of the Triton's shell swelling upon the ear as the
invisible pageant sweeps by.

On the shores of this wondrous isle the kraken heaves its unwieldy bulk and wallows many a rood. Here the sea-serpent, that mighty but much-contested reptile, lies coiled up during the intervals of its revelations to the eyes of true believers. Here even the Flying Dutchman finds a port, and casts his anchor, and furls his shadowy sail, and takes a brief repose from his eternal cruisings.

In the deep bays and harbors of the island lies many a spellbound ship, long since given up as lost by the ruined merchant. Here, too, its crew, long, long bewailed in vain, lie sleeping from age to age in mossy grottos, or wander about in pleasing oblivion of all things. Here in caverns are garnered up the priceless treasures lost in the ocean. Here sparkles in vain the diamond and flames the carbuncle. Here are piled up rich bales of Oriental silks, boxes of pearls, and piles of golden ingots.

Such are some of the marvels related of this island, which may serve to throw light upon the following legend, of unquestionable truth, which I recommend to the implicit belief of the reader.

Success and decline

Quite interesting. Why does Singapore have such a low birth rate? by Tyler Cowen. Singapore is a fascinating little country. As multicultural as the US and probably the world's best argument (for the time being) for the potential efficacy of government policy. Whether sustainable and whether replicable elsewhere is entirely debatable.

The article is a useful recapitulation of sociological and demographic debates in a very small, controlled environment. Cowen identifies eight factors potentially affecting/suppressing fertility and provides the Singapore specific data for each. However, much that is said in this instance is applicable elsewhere, just without so much clarity. My summary of his summary:

1) Singapore educates well and education is correlated with reduced fertility.
2) Singapore has a high cost of living which makes children expensive which, ceteris paribus, reduces demand for children.
3) Singapore has a lot more entertaining distractions than in the past, raising the opportunity cost of children.
4) Singaporean women have greater economic and professional opportunity raising their specific opportunity costs for children.
5) Traditional cultural expectations of women in Singapore are demanding and inflexible, making the incompatibility between careers and family more stark than in other countries.
6) Government pronatalism propaganda is ineffective.
7) Singapore is inescapably dense and density has a negative correlation with fertility.
8) Child care and related subsidies are insufficient to outweigh the above factors.

The real productivity competition is between familial models not between genders

Two very recent and very interesting economic papers on the gender wage gap. It has long been known based on evidence across the OECD that most of the gap is attributable to several common-sense factors: degree level, type of profession, work hour volume, sector, labor force participation continuity, and part-time/full-time. Factor in these obvious variables and the wage gap shrinks dramatically, usually to close to the margin of error of measurement.

This much has been known for the better part of ten or twenty years though it has been largely ignored in popular discussions. What has been missing from much of the research has been one further factor which has always been obvious to me in my management consulting career, both managing consulting business units around the world as well as implementing HR systems for global and national clients. That missing factor is the value of the marginal hour.

Claudia Goldin tackles this pretty directly and rather cleverly in A Grand Gender Convergence, just out today. The issue is that not all hours are created equal in all industries. In Goldin's terms, some industries have linear compensation (more hours worked yield proportionally more income on a direct linear basis) and other industries have non-linear compensation (more hours worked yield a disproportionately greater income). With a linear compensation industry, if you work 10% more hours you will see your income increase by 10%. In a non-linear compensation industry, if you work 10% more hours, you might see your income increase by 20%. Non-linear compensation is also often referred to as winner-take-all markets.

Part of the non-linear effect is based on the old adage, practice makes perfect. More hours of practice make you better and better, even if only incrementally so. Even though there might be a declining rate of improvement for each increment, in a competitive, transparent market where there are high returns to the customer, there can still be outsized returns to small increments of improvement. If you need heart surgery, what is your demand elasticity, if you have the resources, for the best surgeon? Pretty low. Obviously you would be willing to pay significantly more than the average person to obtain the best, even if the cardiac surgeon is only marginally better than the next best.

In industries characterized by high reward, high competition, high growth, high transparency, where compensation is predominantly in objective and empirical terms such as money (as opposed to status or some other murkier form of compensation) there is usually non-linear, winner-take-all compensation. Examples of non-linear, winner-take-all markets include music, sports, chess, mathematics, film, art, hard sciences, law, finance, management consulting, etc. Specialized fields within some industries also often are characterized by non-linear compensation (for example surgeons versus general practitioner MDs in the field of healthcare).

In my profession of management consulting, two professionals of equal educational attainment and experiential background might both work 50 hours a week. However, the nature of the business is such that client's demands and needs change on short notice, projects come off the tracks and other unplanned events occur. The employee who is able to pack in 60 hours one week and only 40 the next in order to fly out to deal with an emergency or spend extra time with a struggling client is worth much more than an employee who works the steady 50 hours and cannot deviate from that schedule.

This variable marginal hour value is huge in most competitive industries and it is a compounding issue. The employee who puts in the same volume of hours but deals with a broader variety of client problems gains much broader, and therefore greater value, experience than the one who simply performs the routine work that can be fit to a less flexible schedule.

In the past, this issue of marginal hour value has been substantially ignored because the data is scarce and it is hard to model. Goldin begins to water that desert.

Goldin indicates that there is little empirical data to support alternate explanations of wage gap differentials (such as discrimination) and that most of the gap is explained by the obvious issues such as full-time versus part-time, etc. She then goes on to show that much of the remaining unexplained residual gaps is attributable to the premium placed on the marginal hour value in terms of hour volume flexibility (ability to increase volume hours when necessary) and hour schedule adaptability (ability to work non-standard hours such as evenings, weekends and holidays) and schedule flexibility (ability to adjust schedule on short notice).

From her paper, footnotes omitted.

But what can explain the residual portion of the gap that now remains? There are many contenders. Some would claim that earnings differences for the same position are due to actual discrimination. To others it is due to women’s lower ability to bargain and their lesser desire to compete. And still others blame it on differential employer promotion standards due to gender differences in the probability of leaving.

A better answer, I will demonstrate, can be found in an application of personnel economics. The explanation will rely on labor market equilibrium with compensating differentials and endogenous job design.

As women have increased their productivity enhancing characteristics and as they “look” more like men, the human capital part of the wage difference has been squeezed out. What remains is largely how firms reward individuals who differ in their desire for various amenities. These amenities are various aspects of workplace flexibility. Workplace flexibility is a complicated, multidimensional concept. The term includes the number of hours to be worked and also the need to work particular hours, to be “on call,” give “face time,” be around for clients, be present for group meetings and so forth. Because these idiosyncratic temporal demands are generally more important for the highly-educated workers, I will emphasize the college educated and occupations at the higher end of the earnings distribution.

[snip]

The main takeaway is that what is going on within occupations—even when there are 469 of them as in the case of the Census and ACS - is far more important to the gender gap in earnings than is the distribution of men and women by occupations. That is an extremely useful clue to what must be in the last chapter. If earnings gaps within occupations are more important than the distribution of individuals by occupations then looking at specific occupations should provide further evidence on how to equalize earnings by gender. Furthermore, it means that changing the gender mix of occupations will not do the trick.

[snip]

Whenever an employee does not have a perfect substitute nonlinearities can arise. When there are perfect substitutes for particular workers and zero transactions costs, there is never a premium in earnings with respect to the number or the timing of hours. If there were perfect substitutes earnings would be linear with respect to hours. But if there are transactions costs that render workers imperfect substitutes for each other, there will be penalties from low hours depending on the value to the firm.

[snip]

Individuals place different values on the amenity, “temporal flexibility,” and firms or sectors face different costs in providing the amenity.

The only drawback to the paper is that it treats non-linear industries as if it is easy and reasonable to shift from high variability schedules to planned schedules (her solution to the remaining wage gap). With changing law, regulations, technology and social standards, it is always conceivable that that might be achievable, in practice it is relatively uncommon. Goldin provides evidence for how and why it occurred in the Pharmacy sector but it is hard to see how the necessary changes could be brought about elsewhere.

The other paper is Degrees Are Forever: Marriage, Educational Investment, and Lifecycle Labor Decisions of Men and Women by Mary Ann Bronsony. Bronsony is not looking specifically at marginal hour value and non-linearity, though she covers some similar ground. She is examining, as the paper title intimates, the degree to which a college degree functions as a form of life-cycle insurance policy for women, particularly in the context of divorce. From her abstract.

Women attend college today at much higher rates than men. They also select disproportionately into low-paying majors, with almost no gender convergence along this margin since the mid-1980s. In this paper, I explain the dynamics of the gender differences in college attendance and choice of major from 1960 to 2010. I document first that changes in returns to skill over time and gender differences in wage premiums across majors cannot explain the observed gender gaps in educational choices. I then provide reduced-form evidence that two factors help explain the observed gender gaps: first, college degrees provide insurance against very low income for women, especially in case of divorce; second, majors differ substantially in the degree of work-family flexibility they offer, such as the size of wage penalties for temporary reductions in labor supply.

Her findings also tip the hat at the ever present danger of unintended consequences despite honest efforts.

My results show that some family-friendly policies increase the share of women in science and business majors substantially, while others further widen both college gender gaps.

Specifically, in an environment where there is generous paid maternity leave, "the model predicts that the policy increases both college gender gaps" and "Under the maternity leave policy women accumulate less experience by their mid to
late-thirties, and thus have lower wages later in life." For part-time work entitlement policies, "the policy has one main effect on women's lifecycle labor supply: women choose to supply less labor to the market over most of their lifetime." Finally she looks at the implications of fully-subsidized child-care. Here, "The policy increases the labor supply of college women in the model mostly in their early childbearing years." However, there is an unintended class consequence. In other words, everyone pays indirectly for the fully funded childcare but the primary beneficiaries are college educated women in science/business occupations.

You always have to be careful of complex models, economic and otherwise. The greater the complexity, the more likely it is that there are false assumptions built into them. These only manifest themselves when many parties use the models under many circumstances, over time. Any new model, regardless of the conclusions, has to be in the wait-and-see category of evidence.

Both these papers help move the knowledge frontier outwards. From my perspective it also moves us closer to an honest discussion of the variability in personal trade-off decisions which are far more sophisticated than we have allowed in the past. It also moves us towards the root issue - what policies support the rapid accumulation of an appropriate portfolio of Knowledge, Experience, Skills, Values and Behaviors that allow a person to optimize their personal productivity across a range of unique personal trade-off decisions.

Despite my caution regarding Bronsony's model and its conclusions, it should be noted that the answers are compatible with the rather ironic comparison of gender policies in the US with those in Sweden. Sweden has the lengthy guaranteed maternity leaves, affordable childcare, and access to part-time schedules that are often advocated for in the US. The consequence though is exactly the opposite of the supposed justification. These policies are supposed to make it easier for women to have both careers and children. However, compared to the US, the gender wage gap is much higher in Sweden and the labor market is much more segregated than in the US. Whereas in the US women are represented in virtually all fields including at the top of all fields, women in Sweden are heavily concentrated in Government employment and in the caring industries (education, childcare, healthcare and eldercare). These outcomes are exactly what Bronsony's model predicts. As she alludes to in the article, there is a conflict of goals. Do we want to make it easier for women to have careers or do we want to make it easier for them to have children. The policies being pursued in Sweden make it easy for them to have children. Counter-intuitively, those in the US make it easier for them to have careers.

Finally, these papers begin to move us towards a truly interesting and challenging discussion. We are accustomed to frame this as equity in terms of gender individualism, i.e. group averages of individual males and individual females. I suspect the real issue is much more complicated. We ought to be framing the discussion in terms of optimum life-time productivity for familial units. This was much the message in Charles Murray's recent book, Coming Apart.

The following graphic does not do the complexities of the issue justice but I think does capture some of the complex trade-offs. None of the bars are measured, merely indicative of relative outcomes. On the bottom axis you have education attainment (did not graduate high school, high school graduate and or some college, and college graduate and or higher) matched with familial structure (single parent, single, married). The vertical axis is life time accumulated earnings per adult person in the household by quintile where Quintile One is the top 20% of people in terms of life time earnings. I have left off the complicating issue of divorce which has a major impact on life earnings. I have also omitted, except in the furthest right column, to separate the distinctly different outcomes of married couples in terms of one earner, two equal earners or one primary and one secondary earner. Interestingly, for reasons discussed by Goldin, married with a primary and secondary income structure tend to do better than married, equal earners.

At each educational attainment level, single parenthood is a huge impediment to productivity as reflected in potential life time earnings. Single people do pretty well but married people do especially well. Interestingly, if you are married (with no children before marriage), completed high school on time and are employed at all, you have less than a 2% chance of being in poverty. The single most effective anti-poverty policy would be one that reduced the number of children born to single parents.

What all this means, and just scratching the thin surface to the complexity, is that choices about education attainment and about familial structure dominate your likely life time productivity. How early or late you make those choices and how effectively you are able to carry out those choices are also contributors.

I think the real productivity issue is not about fairness regarding gender equity or race or any of the other common demographic markers. The productivity issue hinges on the competition between familial models. Intact families with significant education attainment and investment beat all other familial productivity models hands down. But what is the role of the government in such a tangled and complex issue, if any? And what are the policies that would be likely to make a difference? Deep, fraught and complex waters

Food production systems evolved as a result of the accumulation of many separate decisions about allocating time and effort

From Guns, Germs, and Steel: The Fates of Human Societies by Jared Diamond, page 107. Running through the book so far is a sub-theme which has not emerged as anything explicit - that some complex outcomes are not arrived at via intent but through the evolutionary pressures of individual tactical decisions in a complex environment yielding an aggregate outcome that was not anticipated, might not even have been conceivable, in advance. It is essentially the sociological/economic equivalent of the human eye which was long a bugbear for evolutionary theory - how do you explain the intermediate evolutionary steps that get you to the remarkable human eye when there is no apparent value to the eye except as a complete and finished feature? That was eventually explained but Diamond is dealing with similar issues regarding the transition from hunter gather economies to settled agriculture.

I must say that I think this idea of (r)evolutionary outcomes arising from the aggregation of innumerable tactical decisions dealing with pressing short term problems is an intriguing one and one which I suspect has greater importance than we acknowledge.

The underlying reason why this transition was piecemeal is that food production systems evolved as a result of the accumulation of many separate decisions about allocating time and effort. Foraging humans, like foraging animals, have only finite time and energy, which they can spend in various ways. We can picture an incipient farmer waking up and asking: Shall I spend today hoeing my garden (predictably yielding a lot of vegetables several months from now), gathering shellfish (predictably yielding a little meat today), or hunting deer (yielding possibly a lot of meat today, but more likely nothing)? Human and animal foragers are constantly prioritizing and making effort-allocation decisions, even if only unconsciously. They concentrate first on favorite foods, or ones that yield the highest payoff. If these are unavailable, they shift to less and less preferred foods.

Many considerations enter into these decisions. People seek food in order to satisfy their hunger and fill their bellies. They also crave specific foods, such as protein-rich foods, fat, salt, sweet fruits, and foods that simply taste good. All other things being equal, people seek to maximize their return of calories, protein, or other specific food categories by foraging in a way that yields the most return with the greatest certainty in the least time for the least effort. Simultaneously, they seek to minimize their risk of starving: moderate but reliable returns are preferable to a fluctuating lifestyle with a high time-averaged rate of return but a substantial likelihood of starving to death. One suggested function of the first gardens of nearly 11,000 years ago was to provide a reliable reserve larder as insurance in case wild food supplies failed.

Conversely, men hunters tend to guide themselves by considerations of prestige: for example, they might rather go giraffe hunting every day, bag a giraffe once a month, and thereby gain the status of great hunter, than bring home twice a giraffe's weight of food in a month by humbling themselves and reliably gathering nuts every day. People are also guided by seemingly arbitrary cultural preferences, such as considering fish either delicacies or taboo. Finally, their priorities are heavily influenced by the relative values they attach to different lifestyles—just as we can see today. For instance, in the 19th-century U.S. West, the cattlemen, sheepmen, and farmers all despised each other. Similarly, throughout human history farmers have tended to despise hunter-gatherers as primitive, hunter-gatherers have despised farmers as ignorant, and herders have despised both. All these elements come into play in people's separate decisions about how to obtain their food.

The birth interval for many farm peoples is around two years, half that of hunter-gatherers

From Guns, Germs, and Steel: The Fates of Human Societies by Jared Diamond, page 88. Diamond discusses the advantages of food production (herding and agriculture) over the hunter-gatherer economy. What seems obvious to us now in hindsight was not particularly foreseeable at the time. In the transition from hunter-gatherer to settled agriculture there are a number of costs. Farmers work harder, longer, and die younger, on average than hunter-gatherers. So why transition? In part it is because there are all sorts of interlocking unintended benefits to settled agriculture as illustrated by this discussion.

By selecting and growing those few species of plants and animals that we can eat, so that they constitute 90 percent rather than 0.1 percent of the biomass on an acre of land, we obtain far more edible calories per acre. As a result, one acre can feed many more herders and farmers - typically, 10 to 100 times more - than hunter-gatherers. That strength of brute numbers was the first of many military advantages that food-producing tribes gained over hunter-gatherer tribes.

In human societies possessing domestic animals, livestock fed more people in four distinct ways: by furnishing meat, milk, and fertilizer and by pulling ploughs. First and most directly, domestic animals became the societies' major source of animal protein, replacing wild game. Today, for instance, Americans tend to get most of their animal protein from cows, pigs, sheep, and chickens, with game such as venison just a rare delicacy. In addition, some big domestic mammals served as sources of milk and of milk products such as butter, cheese, and yogurt. Milked mammals include the cow, sheep, goat, horse, reindeer, water buffalo, yak, and Arabian and Bactrian camels. Those mammals thereby yield several times more calories over their lifetime than if they were just slaughtered and consumed as meat.

Big domestic mammals also interacted with domestic plants in two ways to increase crop production. First, as any modern gardener or farmer still knows by experience, crop yields can be greatly increased by manure applied as fertilizer. Even with the modern availability of synthetic fertilizers produced by chemical factories, the major source of crop fertilizer today in most societies is still animal manure specialty of cows, but also of yaks and sheep. Manure has been valuable, too, as a source of fuel for fires in traditional societies.

In addition, the largest domestic mammals interacted with domestic plants to increase food production by pulling ploughs and thereby making it possible for people to till land that had previously been uneconomical for farming. Those plough animals were the cow, horse, water buffalo, Bali cattle, and yak/cow hybrids. Here is one example of their value: the first prehistoric farmers of central Europe, the so-called Linearbandkeramik culture that arose slightly before 5000 B.C., were initially confined to soils light enough to be tilled by means of hand-held digging sticks. Only over a thousand years later, with the introduction of the ox-drawn plough, were those farmers able to extend cultivation to a much wider range of heavy soils and tough sods. Similarly, Native American farmers of the North American Great Plains grew crops in the river valleys, but farming of the tough sods on the extensive uplands had to await 19th-century Europeans and their animal-drawn ploughs.

All those are direct ways in which plant and animal domestication led to denser human populations by yielding more food than did the hunter-gatherer lifestyle. A more indirect way involved the consequences of the sedentary lifestyle enforced by food production. People of many hunter-gatherer societies move frequently in search of wild foods, but farmers must remain near their fields and orchards. The resulting fixed abode contributes to denser human populations by permitting a shortened birth interval. A hunter-gatherer mother who is shifting camp can carry only one child, along with her few possessions. She cannot afford to bear her next child until the previous toddler can walk fast enough to keep up with the tribe and not hold it back. In practice, nomadic hunter-gatherers space their children about four years apart by means of lactational amenorrhea, sexual abstinence, infanticide, and abortion. By contrast, sedentary people, unconstrained by problems of carrying young children on treks, can bear and raise as many children as they can feed. The birth interval for many farm peoples is around two years, half that of hunter-gatherers. That higher birth-rate of food producers, together with their ability to feed more people per acre, lets them achieve much higher population densities than hunter-gatherers.

A separate consequence of a settled existence is that it permits one to store food surpluses, since storage would be pointless if one didn't remain nearby to guard the stored food. While some nomadic hunter-gatherers may occasionally bag more food than they can consume in a few days, such a bonanza is of little use to them because they cannot protect it. But stored food is essential for feeding non-food-producing specialists, and certainly for supporting whole towns of them. Hence nomadic hunter-gatherer societies have few or no such full-time specialists, who instead first appear in sedentary societies.