ARC-Change web page

October 26, 2016

Earlier this year, I posted on a new research project, ARC-Change, on climate change in the Arctic and its consequences for governance and resource industries. The project is now underway, and recently the project web page went online (click logo below to go to the site).


Up the ante on bioeconomic submodels of marine food webs

September 20, 2016

My new paper is available for free download for 50 days (until November 9, 2016). The paper is published in the journal Ecological Economics and discusses modeling of marine food webs such that economic analysis is viable. At the core of our approach lie the ensemble Kalman filter, something I have used earlier. In this new application, we go further in reducing model parameter dimensionality and move beyond the filtering routine to estimate certain structure parameters. We also apply a data transformation that deal with previously overlooked endogeneity in stock level data. We use all this to estimate a model of the largest pelagic fish stocks in the Norwegian Sea. The abstract:

eeWhile economists have discussed ecosystem-based fisheries management and similar concepts, little attention has been devoted to purposeful modeling of food webs. Models of ecosystems or food webs that make economic analysis viable should capture as much as possible of system structure and dynamics while balancing biological and ecological detail against dimensionality and model complexity. Relevant models need strong, empirical content, but data availability may inhibit modeling efforts. Models are bound to be nonlinear, and model and observational uncertainty should be included. To deal with these issues and to improve modeling of ecosystems or food webs for use in ecosystem-based fisheries management analysis, we suggest the data assimilation method ensemble Kalman filtering. To illustrate the method, we model the dynamics of the main, pelagic species in the Norwegian Sea. In order to reduce parameter dimensionality, the species are modeled to rely on a common carrying capacity. We also take further methodological steps to deal with a still high number of parameters. Our best model captures much of the observed dynamics in the fish stocks while the estimated model error is moderate.

The paper is part of the EINSAM project.

Harvest control rules in modern fisheries management

August 5, 2016

My latest paper is joint work with a rather large group of people. We met at a workshop two years ago, and after interesting and fruitful discussions, we decided to write a paper based on our work there. After a long and winding process, the paper is now published in the open-access journal ElementaThe abstract reads as follows:

Harvest control rules have become an important tool in modern fisheries management, and are increasingly adopted to provide continuity in management practices, to deal with uncertainty and ecosystem considerations, and to relieve management decisions from short-term political pressure. We provide the conceptual and institutional background for harvest control rules, a discussion of the structure of fisheries management, and brief introductions to harvest control rules in a selection of present day cases. The cases demonstrate that harvest control rules take different forms in different settings, yet cover only a subset of the full policy space. We conclude with views on harvest control rules in future fisheries management, both in terms of ideal and realistic developments. One major challenge for future fisheries management is closing the gap between ideas and practice.

The paper is part of the special feature Climate change impacts: Fish, fisheries, and fisheries management:

The atmosphere and oceans are warming, seasonal sea ice is retreating and salinity and ocean circulation patterns are changing, all of which can impact fish populations. Largely using comparative analyses, this Special Feature examines some of the effects of climate changes on fish stocks in the northern hemisphere, particular in the Northeast Atlantic and around the continental United States. It considers what marine ecosystems may look like under anthropogenic climate change and how existing fisheries management strategies, such as Harvest Control Rules, may fare in the future. It also notes some potential economic and societal consequences of climate change.


Technical Change as a Stochastic Trend in a Fisheries Model

June 3, 2016

Right, I have a couple of things forthcoming. One is, as the post-title suggests, on technical change in fisheries, where I, in my first sole-authored paper in five years, suggest a state space approach to measure technical change in fisheries. The approach is applied to data from the Norwegian Lofoten cod fishery, a data set that previously has been analyzed with other, more typical methods (linear regressions).

The paper has a long history. It started in 2008, when I was a visiting grad student at the economics department of the University of California, San Diego (UCSD). There, Dale Squires, who I am proud to call my friend, presented an analysis of the Lofoten data. During my visit to UCSD, I had spent considerable time studying state space models and the Kalman filter, and during Dale’s talk I wondered whether a state space model would do a better job in estimating technical change. Dale’s analysis was published in 2010, at a time when I already had acquired the data and had started to develop a model and an algorithm. In 2011, during a train trip, I started to get promising results. Progress was doomed to be slow, however, because the entire project was a side project that I only worked on in short stints every now and then. At some point in 2012, I nevertheless had a manuscript ready for submission. I sent it to the same journal where Dale’s analysis was published. After an interesting and instructive review-process, the manuscript was rejected. In the years that followed, the manuscript was sent to a handful of journals (the manuscript took various forms over the years; condensed into the letter-format at one point), but the verdict was always the same: rejection. Over these years, Dale, who I kept in touch with, was always optimistic and encouraging, suggesting alternative journals. Early in 2015, the manuscript was finally sent to Marine Resource Economics, where it was accepted after no less than three rounds of revisions. In the last round, I had to pull out my initial version, written more than three years earlier, and add discussion that was revised out at some point along the road but which obviously had its place. The manuscript was formally accepted early this year (2016), eight years after I had the initial idea.

Late in 2014, more than six years into the process, I had another idea for how to carry out the analysis. I decided to pursue this new idea in another side project. This spin-off project had much faster progress, and less than six months later, a letter-form manuscript was already rejected. After some further work, expanding the manuscript to the more typical article form, the manuscript was submitted again, and I am now awaiting its review. This much faster progress on the second side project is partly taken, by me, as evidence that I have become better at what I do. The lower degree of complexity is, of course, also an important factor in the progress.

‘Technical Change as a Stochastic Trend in a Fisheries Model’ will appear in Marine Resource Economics during the fall. The abstract reads as follows:

mreTechnical change is generally seen as a major source of growth, but usually cannot be observed directly and measurement can be difficult. With only aggregate data, measurement puts further demands on the empirical strategy. Structural time series models and the state space form are well suited for unobserved phenomena, such as technical change. In fisheries, technical advances often contribute to increased fishing pressure, and improved productivity measures are important for managers concerned with efficiency or conservation. I apply a structural time series model with a stochastic trend to measure technical change in a Cobb-Douglas production function, considering both single equation and multivariate models. Results from the Norwegian Lofoten cod fishery show that the approach has both methodological and empirical advantages when compared with results from the general index approach, which has been applied in the literature.

UPDATE: The article is now available here:
DOI: 10.1086/687931

Schizophrenic Work Ethics

May 10, 2016

In the big picture, I think of my work in two ways. First, the world’s resources are scarce and often mismanaged. There exist a seemingly constant conflict between want of development and necessity of conservation. My research into environmental and resource economics are small but potentially important contributions towards these issues. My work will almost certainly have no effect in the short run but may have a some effect in the longer run. Devoting my admittedly limited intellectual powers to this end form a motivation to put up with the many irrational incongruencies of present day academia and, according to some, low pay. (My view towards the latter vary, largely in phase with the size of my bank account.)

Second, we are just small, insignificant critters basking in a soup of organic chemistry on a speck of dust in an enormous universe that we hardly understand. My work has no significance, but I sometimes like doing it.

It is in the latter way I often understand art. Life is utterly meaningless, so why not make something beautiful.

New Research Project on Climate Change and the Arctic

April 5, 2016

I will take part in a new research project on climate change in the Arctic. The project carries the long name “ARCtic Marine Resources under Climate Change: Environmental, Socio-Economic Perspectives and Governance,” or ARC-Change for short. From the project description:

As we enter the Anthropocene, climate change moves the parameters we live within. First and foremost, these changes will take place in Arctic regions, regions that already are subject to substantial, large scale natural variability and where higher temperatures and retreating sea ice will redefine boundaries of biological life, ecological structure, and commercial and social opportunities. Complex interactions and causal mechanisms exist from the physical impact, in terms of temperature, ocean currents, via biological and ecological adaptations, in terms of habitat expansion, growth conditions, species interactions, via social and business enterprise, in terms of new fishing areas, trade routes, mineral wealth, to governance implications, in terms of pressure on existing agreements on fishing, surveillance, and commercial activity. A cross-sectorial and cross-disciplinary perspective is needed to investigate and understand climate change impacts. ARC-Change will study some of these interlinkages, from the physical and biological to the economical and governmental, while brining together expertise from an array of disciplines and institutions.

More in the press release.

Optimal maintenance scheduling for local public purpose buildings

April 1, 2016

New paper forthcoming, something other than fish this time. The abstract:

We formulate the maintenance scheduling decision as a dynamic optimization problem, subject to an accelerating decay. This approach offers a formal, yet intuitive, weighting of an important trade-off when deciding a maintenance schedule.

The optimal maintenance schedule reflects a trade-off between the interest rate and the rate at which the decay accelerates. The prior reflects the alternative cost, since the money spent on maintenance could be saved and earn interests, while the latter reflects the cost of postponing maintenance. Importantly, it turns out that it is sub-optimal to have a cyclical maintenance schedule where the building is allowed to decay and then be intensively maintained before decaying again. Rather, local governments should focus the maintenance either early in the building’s life span and eventually let it decay towards replacement/abandonment or first let it decay to a target level and then keep it there until replacement/abandonment. Which of the two is optimal depends on the trade-off between the alternative cost and the cost of postponing maintenance.

The paper provides a first formal inquiry into important trade-offs that are important for maintenance scheduling of local public purpose buildings.

Quotes from The Ordeal of Change by Eric Hoffer

September 27, 2015

Eric Hoffer is a very interesting thinker, and I very much enjoyed his The Ordeal of Change. If possible, I would quote large parts of the book, but have to settle for some short excerpts. Many of them demonstrate Hoffer’s deep understanding of the human psyche. I try to quote generously rather than commenting too much.

It has been often said that power corrupts. But it is perhaps equally important to realize that weakness, too, corrupts. Power corrupts the few, while weakness corrupts the many. Hatred, malice, rudeness, intolerance, and suspicion are the fruits of weakness. The resentment of the weak does not spring from any injustice done to them but from the sense of their inadequacy and impotence. We cannot win the weak by sharing our wealth with them They feel our generosity as oppression. […] Nor can we win the weak by sharing our hope, pride, or even hatred with them. […] Our healing gift to the weak is the capacity for self-help. We must learn how to impart to them the technical, social, and political skills which would enable them to get bread, human dignity, freedom, and strength by their own efforts [pp. 11-12*].

While written more than fifty years ago, certain parts feel oddly relevant for the present-day social media driven self-realization epidemic:

An autonomous existence is heavily burdened and beset with fears, and can be endured only when bolstered by confidence and self-esteem. The individual’s most vital need is to prove his worth, and this usually means an insatiable hunger for action. For it is only the few who can acquire a sense of worth by developing and employing their capacities and talents. The majority prove their worth by keeping busy. A busy life is the nearest thing to a purposeful life. But whether the individual takes the path of self-realization or the easier one of self-justification by action he remains unbalanced and restless. For he has to prove his worth anew each day [p. 25].

On creativity of the intellectual:

There is no unequivocal evidence that the intellectual is at his creative best when left wholly on his own. It is not at all certain that individual freedom is a vital factor in the release of creative energies in literature, art, music, and science. Many of the outstanding achievements in these fields were not realized in an atmosphere of absolute freedom. […] There is a chronic insecurity at the core of the creative person, and he needs a milieu that will nourish his confidence and sense of uniqueness. Discerning appreciation and a modicum of deference and acclaim are probably more vital for his creative flow than freedom to fend for himself. Thus a despotism that recognizes and subsidizes excellence might be more favorable for the performance of the intellectual than a free society that does not take him seriously. […] It is of course conceivable that a wholly free society might become imbued with a reverence for the fine arts; but up to now the indications have been that where common folk have room enough there is not much room for the dignity and rank of the typical writer, artist, and intellectual in general [pp. 31-32].

More on the intellectual:

One cannot escape the impression that the intellectual’s most fundamental incompatibility is with the masses. He has managed to thrive in social orders dominated by kings, nobles, priests, and merchants, but not in societies suffused with the tastes and values of the masses. The trespassing by the masses into the domain of culture and onto the stage of history is seen even by the best among the intellectuals as a calamity [pp. 42-43].

Ordeal is not really a book in the typical sense, but rather a collection of essays that revolve around a common theme. Thus, Hoffer ranges far and wide in topics and relations, and takes the opportunity to comment on, for example, history:

From their first appearance civilizations almost everywhere were preoccupied with the spectacular, the fantastic, the sublime, the absurd, and the playful—with hardly a trickle of ingenuity seeping into the practical and useful. The prehistoric discoveries and inventions remained the basis of everyday life in most countries down to our time. Technologically, the Neolithic Age lasted even in Western Europe down to the end of the eighteenth century [p. 48].

In an essay on ‘the brotherhood of men’, Hoffer points out a surprisingly accurate contrast between my relationship with those close and humanity in general. (But I remain ambivalent, and my relationships are repeatedly turned up side down. Perhaps I need the maturity of Hoffer to settle.)

It is easier to love humanity as a whole than to love one’s neighbor. There may even be a certain antagonism between love of humanity and love of neighbor; a low capacity for getting along with those near us often goes hand in hand with a high receptivity to the idea of the brotherhood of men. […] The capacity for getting along with our neighbor depends to a large extent on the capacity for getting along with ourselves. The self-respecting individual will try to be as tolerant of his neighbor’s shortcomings as he is of his own. Self-righteousness is a manifestation of self-contempt. When we are conscious of our worthlessness, we naturally expect others to be finer and better than we are, and it is as if we wished to be disappointed in them. Rudeness luxuriates in the absence of self-respect [pp. 74-75].

According to Hoffer, modern man strives with self-respect, and with a certain grandeur, he connects it with global conflict.

The unattainability of self-respect has […] grave consequences. In man’s life the lack of an essential component usually leads to the adoption of a substitute. The substitute is usually embraced with vehemence and extremism, for we have to convince ourselves that what we took as second choice is the best there ever was. Thus blind faith is to a considerable extent a substitue for the lost faith in ourselves; insatiable desire a substitute for hope; accumulation a substitute for growth; fervent hustling a substitute for purposeful action; and pride a substitute for unattainable self-respect .The pride that at present pervades the world is the claim that one is a member of a chose group—be it a nation, race, church, or party. No other attitude has so impaired the oneness of the human species and contributed so much to the savage strife of our time [p. 76].

On the writer:

To the genuine writer the word is an end in itself and the center of his existence. He may dream of spectacular action and be lured to play an active role, but in the long run he does not feel at home in the whirl of busy life. […] It is only when the creative flow within him materializes in serried ranks of words that he feels at home in the world [p. 87].

Playfulness and creativity:

[…] the tendency to carry youthful characteristics into adult life, which renders man perpetually immature and unfinished, is at the root of his uniqueness in the universe, and is particularly pronounced in the creative individual. Youth has been called a perishable talent, but perhaps talent and originality are always aspects of youth, and the creative individual is an imperishable juvenile. When the Greeks said, “Whom the gods love die young” they probably meant, as Lord Sankey suggested, that those favored by the gods stay young till the day they die; young and playful [p. 93].

* Page numbers refer to the limited edition printed by Buccaneer Books, Inc. The Ordeal of Change was first published in 1963.

Related post:

Qualifications for an economist

September 25, 2015

In The Worldly Philosophers, Robert L. Heilbroner brings this quote from Keynes on the qualifications for an economist. I’ve posted parts of this before, but it is worth repeating:

The study of economics does not seem to require any specialized gifts of an unusual high order. Is it not, intellectually regarded, a very easy subject compared with the higher branches of philosophy or pure science? An easy subject, at which very few excel!  The paradox finds its explanation, perhaps, in that the master-economist must possess a rare combination of gifts. He must be mathematician, historian, statesman, philosopher – in some degree. He must understand symbols and speak in words. He must contemplate the particular in terms of the general, and touch abstract and concrete in the same flight of thought. He must study the present in the light of the past for the purpose of the future. No part of man’s nature of his institutions must lie entirely outside his regard. He must be purposeful and disinterested in a simultaneous mood; as aloof and incorruptible as an artist, vet sometimes as near the earth as a politician.

The Ensemble Kalman Filter for Multidimensional Bioeconomic Models

September 22, 2015

Natural Resource ModelingIn the recent issue of Natural Resource Modeling, I have an article together with my old boss. The idea is to apply the ensemble Kalman filter to fit multidimensional foodweb models to data for use in bioeconomic analysis. The abstract:

To integrate economic considerations into management decisions in ecosystem frameworks, we need to build models that capture observed system dynamics and incorporate existing knowledge of ecosystems, while at the same time accommodating economic analysis. The main constraint for models to serve in economic analysis is dimensionality. In addition, to apply in long-term management analysis, models should be stable in terms of adjustments to new observations. We use the ensemble Kalman filter to fit relatively simple models to ecosystem or foodweb data and estimate parameters that are stable over the observed variability in the data. The filter also provides a lower bound on the noise terms that a stochastic analysis requires. In this paper, we apply the filter to model the main interactions in the Barents Sea ecosystem. In a comparison, our method outperforms a regression-based approach.

Classic Style according to Steven Pinker

August 6, 2015

Steven Pinker has a piece on that has much of the essence of his book The Sense of Style. In the Chronicle-piece, he describes classic style, which he promotes as the best style for academic writing, more condensed and, honestly, more quotable than I ever remember from Sense:

The guiding metaphor of classic style is seeing the world. The writer can see something that the reader has not yet noticed, and he orients the reader so she can see for herself. The purpose of writing is presentation, and its motive is disinterested truth. It succeeds when it aligns language with truth, the proof of success being clarity and simplicity. The truth can be known and is not the same as the language that reveals it; prose is a window onto the world. The writer knows the truth before putting it into words; he is not using the occasion of writing to sort out what he thinks. The writer and the reader are equals: The reader can recognize the truth when she sees it, as long as she is given an unobstructed view. And the process of directing the reader’s gaze takes the form of a conversation.

Prose is a Window Onto the World!

I will let the problems of ‘truth’ lie for the moment, but I do think writing and thinking is intertwined and one promotes the other. Writing can be used to sort out what one thinks. (I have this idea from good, old McCloskey and find it compelling.) But this is not to say that the final, rewritten, rewritten, and edited text should read as if the writer sorted out thoughts along the way, which I presume is what Pinker has in mind and with which I agree.

Stochastically Induced Critical Depensation and Risk of Stock Collapse

July 9, 2015

mreMy research team has published a paper in the latest issue of Marine Resource Economics (vol. 30, no. 3). The paper is called Stochastically Induced Critical Depensation and Risk of Stock Collapse and discusses how stochasticity induces depensation in fisheries models. We also develop a measure of stock collapse risk and apply it to a model with an optimal harvest rate. The abstract reads as follows:

This article investigates the risk of stock collapse due to stochastically induced critical depensation in managed fisheries. We use a continuous-time surplus production model and an economic model with downwardsloping demand and stock-dependent costs. First, we derive an optimal exploitation policy as a feedback control rule by applying the Hamilton-Jacobi-Bellman approach and analyze the effects of stochasticity on the optimal policy. Then, we characterize the long-term sustainable optimal state and estimate the risk of stock collapse due to stochastically induced critical depensation. We find that the optimal harvest policy in the stochastic setting is conservative at low stochasticity and approaches the myopic solution at high stochasticity. The risk of stock collapse is increasing with the stochasticity and decreasing with stock sizes.

The Sense of Style by Steven Pinker

June 11, 2015

Steven Pinker’s The Sense of Style is one of the best books about writing that I have read. (Not that I have read that many books about writing, but I have read some. Those that comes to mind are Strunk and White’s The Elements of Style — didn’t leave much of an impression — Deidre McCloskey’s Economical Writing — did leave a huge impression — much of Barzun’s Simple & Direct and William’s Style — that I didn’t finish them says a lot — Stephen King’s On Writing and the edited volume Ernest Hemingway On Writing — King and Hemingway are not exclusively, but still largely, on writing. Further reading on rhetorics are McCloskey’s The Rhetorics of Economics and Cicero’s De Oratore. Books about reading — surprisingly readable — include Nick Hornby’s Shakespeare Wrote for Money and Stephen Jay Gould’s The Urchin in the StormUrchin is a collection of essays where Gould pursues a special kind of book review, discussing books in an idea-wide scope; as instructive as anything. But I get carried away.)

Pinker’s The Sense of Style is great, perhaps only surpassed by McCloskey’s Economical Writing, in part because of McCloskey’s brevity. But Pinker has so much knowledge and so much to tell; he will be forgiven. What I get from McCloskey and that I miss in Pinker is an account of, and introduction to, the struggle of writing — writing obviously comes easily to Pinker and it seemingly never struck him that people struggle with it and that dealing with this struggle is, sometimes, half the job. Further, McCloskey tells us of the importance of reading well in order to write well; I think McCloskey has an important point that is missed by many, and I would appreciate Pinker’s views on it. Another minor thing pointed out by McCloskey is the value of prudence when it comes to visual effects like italics and bold face, and the disadvantage of distractions like footnotes (the latter pertains in particular to non-fictional writing, of course); I also miss these perspectives in Pinker.

But (again) Pinker is a very great book on writing. He starts out by providing samples of great writing (one example here) and then explaining, in details, what’s so particularly great about the specific examples. (Pinker uses a lot of examples — perhaps too much.) Next, he introduces the classic style, the style of writing he recommend, in particular for clear, non-fictional writing.

Classic style is an ideal. Not all prose should be classic, and not all writers can carry off the pretense. But knowing the hallmarks of classic style will make anyone a better writer, and it is the strongest cure I know for the disease that enfeebles academic, bureaucratic, corporate, legal, and official prose [p. 31*].

To just adopt the classic style is not all that easy, however, and this is one place where I wish Pinker would take a lesson from McCloskey. While Pinker teaches us what the classic style is and why it works, I missed something on how to achieve it. (Perhaps it’s all there, but I didn’t get it?)

Pinker moves on to discuss the curse of knowledge that is the difficulty involved in understanding what your reader knows and what your reader does not know, and our tendency to overestimate what is known. Pinker advice to “always try to lift yourself out of your parochial mindset and find out how other people think and feel” (p. 76).

Then Pinker turns to grammar, that old-fashioned subject that will bore you to death (or so must they think, those who think the grammar support provided by most word processing softwares nowadays is sufficient):

But grammar should not be thought of as an ordeal of jargon and drudgery […] It should be thought of instead as one of the extraordinary adaptations in the living world: our species’ solution to the problem of getting complicated thoughts from one head to another. Thinking of grammar as the original sharing app makes it much more interesting and much more useful. By understanding how the various features of grammar are designed to make sharing possible, we can put them to use in writing more clearly, correctly, and gracefully [p. 79].

Grammar brings together three things: “the web of ideas in our head, the string of words that comes out of our mouth or fingers, and the tree of syntax that converts the first into the second” (p. 79). Pinker spends considerable time on the tree-like structure of sentences; probably both important and useful, but I honestly have forgotten most of it.

One important lesson I do remember, so important that Pinker returns to it on several occasions, is that the passive voice do have a place in good writing, and is even necessary at times:

[Earlier] we saw one of the benefits of the passive, namely that the agent of the event, expressed in the by-phrase, can go unmentioned. This is handy for mistake-makers who are trying to keep their names out of the spot-light and for narrators who want you to know that helicopters were used to put out some fires but don’t think you need to know that it was a guy named Bob who flew one of the helicopters. Now we see the other major benefit of the passive: it allows the doer to be mentioned later in the sentence than the done-to. […] The passive allows a writer to postpone the mention of a doer that is heavy, old news, or both [p. 132].

I find this lesson about the passive extraordinarily important. Ever since I read McCloskey, who dismisses the passive in forceful turns, I have avoided it like the plague. Now, I relax a little bit, knowing that submitting to a passive phrase does not have to mean that I am a useless writer.

Appreciating the treelike nature of a text can also help you understand one of the few devices available in nontechnical prose to visually mark the structure of discourse: the paragraph break. Many writing guides provide detailed instructions on how to build a paragraph. But the instructions are misguided, because there is no such thing as a paragraph. That is, there is no item in an outline, no branch of a tree, no unit of discourse that consistently corresponds to a block of text delimited by a blank line or an indentation. What does exist is the paragraph break: a visual bookmark that allows the reader to pause, take a breather, assimilate what he has read, and then find his place again on the page [p. 145].

Two cents from McCloskey here: Align, in Pinker’s words, the units of discourse with your paragraphs: One idea, one unit of thought, per paragraph, and the structure of your argument will become more clear.

On page 156 and onward, Pinker discusses the imperative Avoid Elegant Variation in the context of one of his many examples. He does, however, also point to situations where it is necessary to avoid repeating words, for example to avoid confusion. But the general advice is still to avoid variation for variation’s sake. Pinker is in full agreement with McCloskey here, who is rather stern if I remember correctly. Variation leads Pinker onto a discussion of coherence, of utmost important to good writers, of course. And coherence is related to the curse of knowledge:

Figuring out the right level of explicitness for coherence relations is a major reason that a writer needs to think hard about the state of knowledge of her readers and show a few of them a draft to see whether she got it right. It’s an aspect of the art of writing which depends on intuition, experience, and guesswork, but there is also an overarching guideline. Humans are cursed with attributing  too much of their own knowledge to others [curse of knowledge], which means that overall there is a greater danger of prose being confusing because it has too few connectives than pedantic because it has too many. When in doubt, connect [pp. 167-168].

I have a rumor (among me and myself, at least) for being pedantic when it comes to writing. Mostly, I find it a valuable trait.

Pinker end up concluding that coherence amounts to design:

There is a big difference between a coherent passage of writing and a flaunting of one’s erudition, a running journal of one’s thoughts, or a published version of one’s notes. A coherent text is a designed object: an ordered tree of sections within sections, crisscrossed by arcs that track topics, points, actors, and themes, and held together by connectors that tie one proposition to the next. Like other designed objects, it comes about not by accident but by drafting a blueprint, attending to details, and maintaining a sense of harmony and balance [p. 186].

I tend to agree.

The final chapter of Pinker’s Style is devoted to a list of hundred common issues in grammar, word choice, and punctuation, with Pinker’s advice on how to navigate them. Among them, the dreaded dangling modifiers, that versus which, a fun story of when fear of a split infinitive lead to a crisis of governance (in the US, of course), and ninety seven more valuable lessons that I am glad I now have available in my office.

I hope to have convinced you that dealing with matters of usage is not like playing chess, proving theorems, or solving textbook problems in physics, where the rules are clear and flouting them is an error. It is more like research, journalism, criticism, and other exercises of discernment. In considering questions of usage, a writer must critically evaluate claims of correctness, discount the dubious ones, and make choices which inevitably trade off conflicting values [p. 300].

I never intended to put Pinker and McCloskey up against each other, but it kind of turned out that way anyhow. (I remember more from McCloskey than I’m aware!) Which I prefer? I think someone who want to write better should read both, but start with McCloskey, for brevity if for nothing else. They complement each other. And I cannot choose. Pinker provide a much more comprehensive treatment, and is much more an expert. McCloskey is refreshing, in particular when she addresses peculiarities of economic writing, and should not be missed. For all her amateurism, her guide made me appreciate the value and necessity of good writing, and provided me with an understanding that let me navigate other treatises with ease and joy.

* Page numbers refer to the first edition, Allen Lane, 2014.


Mathiness in Economics

June 9, 2015

In the Papers & Proceedings section of American Economic Review, Paul Romer* describes, after revealing formal errors in a couple of recent prestigious articles, what he calls the new equilibrium in economics:

[…] empirical work is science; theory is entertainment. Presenting a model is like doing a card trick. Everybody knows that there will be some sleight of hand. There is no intent to deceive because no one takes it seriously.

At a seminar I attended recently, there was debate about the concept of rationality in economics. It was pointed out that any behavior (in the given case discussed, but the claim holds more generally, if not fully) can be rationalized if just the model is rich enough. But then rationality becomes worthless because we cannot falsify it, to use a Popperian term. This may be to take it too far; one can set up a model for rational behavior and find conflicting behavior. While we cannot conclude that behavior was irrational, we can conclude that the model we not rich enough.

Romer discusses mathiness in economics further on his blog.

*Romer, PM (2015) Mathiness in the Theory of Economic Growth, American Economic Review: Papers & Proceedings 105(5): 89-93.

Steven Pinker on ‘that’ vs. ‘which’

May 23, 2015

A recurrent theme for many writers (of English), particularly non-native speakers and especially me, is whether to use ‘that’ or ‘which’. Here is Steven Pinker:

The real decision is not whether to use that or which but whether to use a restrictive or a nonrestrictive clause. If a phrase which expresses a comment about a noun can be omitted without substantially changing the meaning, and if it would be pronounced after a slight pause and with its own intonation contour, then be sure to set it off with commas (or dashes or parentheses): The Cambridge restaurant, which had failed to clean its grease trap, was infested with roaches. Having done so, you don’t have to worry about whether to use that or which, because if you’re tempted to use that it means either that you are more than two hundred years old or that your ear for the English language is so mistuned that the choice of that and which is the least of your worries. [Steven Pinker, The Sense of Style, Allen Lane, 2014.]

I am not two hundred years old, so that or which is the least of my worries; good to know!