Why cost-benefit analysis is a much better context for ecosystem service valuation than natural capital accounts

Help! I just discovered I agree with George Monbiot!

Well, sort of. He makes a number of sensible points against natural capital accounting that are worth considering:

Natural capital accounting suggests substitutability. Prices are substitutions. In a market money is best understood as a numeraire good, a good that has no immediate value of its own but that acts as an intermediary and a yardstick for the value (read: relative scarcity) of all the other commodities. I know natural capital adherents who try to estimate the monetary value of ecosystems, but flinch at any suggestion of it being a “price tag”: ecosystems cannot be substituted, they say. If a commodity cannot be substituted it has an infinite price. Attach a finite number to it, and it becomes substitutable. Period. This means two things. First, as Monbiot rightly argues, a price is meaningless without the suggestion of a transaction. Indeed, much non-market valuation aims at finding the compensating variation of a public good: how much money people should pay (receive) to make them just as happy as if they had not seen the public good reduced (improved). But these are incremental changes, whereas natural capital accounting regards the value of total stocks of capital. Second, if you value the total area of forest at some price (usually the per-hectare value times the area in hectares) you suggest we would be happy if we sold all our forest at that price (plus, say, one euro). But the per-hectare value reflects the marginal value of the first hectare you would cut; by the time you’re done cutting all the forest the last tree will be worth astronomic sums of money.

Pricing something crowds out intrinsic motivations to preserve it. A growing body of social-psychological research demonstrates that this is indeed a risk. A now-classic study demonstrated that when parents were fined for being late to pick up their kids at a day-care centre, they were more likely to be late – paying the fine absolved them of the moral obligation to be on time. Another study demonstrates that when being informed on the economic value of a park, people are less likely to donate money to its conservation.

I don’t think monetary valuation is entirely useless, but I do admit I’m getting more skeptical of natural capital accounting. Originally non-market valuation was developed to be included in cost-benefit analysis, and I think it should stay there. For three reasons:

Cost-benefit analysis has a null option. A properly done CBA compares at least two alternatives: adopting the policy and not adopting the policy. Both alternatives should be defined carefully, so they can be compared on their positive and negative effects on human well-being. NCA has no such null option. Suppose the government wants to build a highway straight through a forest. A CBA would compare two alternatives: one where we keep the forest and accept the traffic jams, and one where we lose the forest but win travel time. Comparing the economic costs and benefits of both alternatives gives us the incremental costs and benefits of building the highway. Now, I know that NCA was never meant to be used in such decisions (which raises for me the question what it is being used for), but the example demonstrates the problem with its lack of a null option: if we lose the forest, what do we have left? There is no proper definition of “no forest”: is it barren land, a hole in the soil, a graveyard of trees? The worst case of valuation-without-context is replacement cost pricing, where the forest is valued by the costs you would make to rebuild it elsewhere if it disappears. In a CBA such rebuilding efforts could be part of your policy alternative, and the CBA will inform you on the merits of that choice. In NCA, however, you would have to assume that the forest would be rebuilt no matter what.

Cost-benefit analysis is done in incremental terms. As rightly pointed out by Monbiot (and, actually, many economists), it is silly to assume that the total value of a biome is equal to its marginal value times its area. In fact, economists developing methods to value natural capital are aware of this, so what they do is to account for the value of natural capital in a way that is consistent with how we calculate GDP. Nevertheless, the very act of valuing all forest in a country yields numbers that are very difficult to interpret, and therefore prone to misinterpretation. In a CBA, both alternatives are defined by a proper storyline and a delineation.

Cost-benefit analysis has a context. CBA is usually done to inform a concrete policy decision, and most of the time it is an input into a wider decision-making process that involves multiple stakeholders. Also, in this process many other values are considered besides economic value, such as social impacts, aesthetics, ethical considerations. Non-market valuation of ecosystem services can be part of this, but one can also choose not to monetize those values, and leave them to a wider debate that can also include other considerations. (I’m currently reading up on taboo trade-offs and the IPBES theoretical framework – exciting stuff!) At best, the valuations done within NCA are included in satellite accounts that also list biophysical parameters such as species richness, forest cover, and air quality. But the wide range of considerations that will feature in the public debate will still be reduced to a set of statistics.

Why (not) price nature?

A few remarks on today’s debate on economic valuation of ecosystem services, here in Wageningen:

  • Having two non-economists as the only speakers in a debate on economic valuation of ecosystem services led to the usual misconceptions of economics, some if which I will explain below.
  • I have written most of what I can say about the issue in this post.
  • In my three-species typology in that post, Dolf de Groot is a typical pragmatic ecologist: he literally called valuation “a necessary evil.”
  • The same typology might label Bram Büscher (a sociologist) a hardcore ecologist, but actually his arguments were more of a Marxist critique of economics and capitalism than of a moral nature (intrinsic value ‘n all). In short his argument is that ecosystem degradation is caused by the logic of capitalism; pricing nature perpetuates that logic rather than abolishing it.
  • De Groot claimed that “conventional economists ignore most externalities, like ecosystem degradation.” As a conventional environmental economist, who has been working on nothing else for the past ten years than externalities and other market failures, and who meets hundreds of similar economists every year at the meetings of EAERE, AERE, IIFET, BIOECON, and so on, I found this very strange to hear, to put it mildly.
  • Another statement by De Groot was that unlike pricing, valuing “is not about substitution.” Economic valuation is ALWAYS about substitution. If you don’t like the idea that people can be compensated for ecological degradation, don’t do valuation. De Groot wants to have his cake and eat it too.
  • It is a more general problem I have with the so-called ‘ecological economists’: a lot of their valuation work is poorly thought through, poorly executed, and done from a political agenda rather than out of scientific curiosity.
  • Common mistakes by ecological economists are (1) not properly defining what they measure (like doing a stated preference survey among tourists to measure indirect use values); (2) aggregating values to such a scale that prices are bound to change (the most fundamental critique of Costanza et al.’s 1997 paper); (3) treating economic values like they would treat biophysical variables such as temperature or density (which are not context-dependent while economic value depends on what question you are asking).
  • Büscher repeated the Suzuki fallacy that “externality” means “not part of the economic system”
  • Büscher “did not have time” to propose an alternative to the capitalist system. Perhaps he should have a look at the historical alternatives to capitalism and their wonderful impact on the environment.
  • Büscher quoted a Chinese philosopher (probably Sun Tzu) that “if you can get your enemy to speak your language you have won the battle” or something in that spirit. I don’t agree. Economists study the rules of market allocation (property rights, taxation, and so on) to understand where such rules work and where they don’t. This would suggest that our advice would always favour big business. But being market-friendly is not the same as being business-friendly.
  • I’m in favour of pricing ecosystem services, but only in the context of concrete policy decisions, in a proper cost-benefit analysis that is part of a wider policy-making process that also takes into account other considerations besides economic value (such as intrinsic value, distribution of effects, and so on). Don’t try to estimate the total value of the planet, as Costanza did.

On interdisciplinarity

Check out the really cool cover of Nature’s special feature on interdisciplinarity!

Of course, as an economist I especially like their inclusion of “Invisible Hand” as the sole superhero representing the social sciences in their scientific team of Avengers. But it is also symbolic for the fact that economists have, in my view, gone the furthest in integrating their discipline with the natural sciences. This holds particularly for environmental and resource economists, who by definition deal with problems of the natural environment like pollution and overfishing. The reason is pretty geeky: most economic research is quantitative, and quite a lot involves the development of mathematical models. And whaddayaknow: so do climate science, population biology, hydrology, and a host of other natural sciences. Give me your equations and I’ll plug them into my CGE model.

It is actually much, much harder to truly integrate qualitative social sciences like sociology or anthropology with quantitative sciences – even with a social science like economics. Models like IMAGE and DICE describe the global climate as well as the economy; the Gordon-Schaefer fisheries model and Colin Clark’s work on renewable resource use, which use basic models from population biology like logistic growth, are part of the standard canon of resource economics since decades; when Daniel Pauly criticizes the limited impact of the “social sciences” on fisheries research, he lumps together economics with biology, not sociology. Meanwhile, it has taken until 2009 that the Nobel committee finally recognized anthropologist Elinor Ostrom for her contributions to the economics of common pool resources, and economists and sociologists share little but contempt for each others’ fields. The Indian economist Jagdish Bhagwati is said to have joked that good economists reincarnate as physicists; wicked economists reincarnate as sociologists. But Ostrom’s Nobel also shows that things are changing, especially in the field of institutional economics. Let’s have more of that in the future.

Burn the schools down

I guess it’s a tradition that every once in a while students revolt against the economics they are being taught. When I was doing my PhD it was a movement calling itself “post-autistic economics”, which was mainly active in France, but also got support elsewhere. I agreed with some of their complaints, although the argumentation was not always that strong and sometimes outright politically motivated (“Capitalism boo! Neo-feminist post-constructionalism yay!”). Later on they changed the name to “Real-World Economics”, perhaps not to offend people suffering from autism. Looking at their review I still don’t get the impression that they’re making much of a dent in the economics debate. Neither am I convinced by what they write, to put it politely.

But now a new revolt has emerged in Manchester. As far as I can see it is more constructive, and more well-argued than the post-autist movement. I agree with some of their points, but not all.

I agree with their proposition that economics teaching should take heed of insights from such fields as psychology, law, and policy science. I don’t know the Manchester program, but I find it curious that such subjects receive as little attention as the Manchester economics students claim. Besides microeconomics, macroeconomics, and econometrics, students in our BSc Economics and Governance program take courses and lectures on history, policy science, institutional economics, and behavioral economics. I guess it’s a question of discussing one particular model or theory very thoroughly, or discussing several different models or theories in a more shallow manner. Our Economics and Governance BSc chooses to be broad, and I agree with that, especially for a problem-oriented university as Wageningen.

I also agree with the Manchester students’ call for a more evidence-based economics, and more attention for the conditions under which different theories and models have more explanatory power than others.

But that’s also where my main objection lies: the call for “pluralism” is translated into more attention to other “schools of thought” than just neoclassical economics. According to the Merriam-Webster Dictionary, a school of thought is

a group sharing a common point of view in respect to some matter (e.g. “she belongs to the liberal school of thought”); also: a point of view recognized as held but not necessarily accepted (e.g. “there are two schools of thought about this question”)

An economist can be “of” a particular school of thought: for example, Paul Krugman is generally considered a Keynesian; Milton Friedman was a monetarist; Herman Daly is an ecological economist; John Kenneth Galbraith was an institutional economist. The natural scientists I work with can only shake their heads when I tell them this. In their fields, there are different theories that compete or need to be reconciled (e.g. general relativity versus quantum mechanics). Or there are different models for different situations, based on simplifying assumptions, and usually developed for a selection of cases but not for all (e.g. metapopulation theory, or the Beverton-Holt stock recruitment model). In that sense, economics is close to ecology: both deal with complex systems that cannot always be experimented on to test competing hypotheses, so we use models that describe a subset of the mechanisms at work. The difference, however, is that whereas even Ilkka Hanski will acknowledge that not all populations can be approached as metapopulations, economists argue as if either Krugman or Friedman is right. On the other hand, schools of thought also have a danger of being politically motivated: if schools of thought are just “points of view”, then you can pick and choose whichever one fits your political preferences. So if you like bow ties, become a Hayekian; if you want to keep your really cool Che Guevara t-shirt, declare yourself a Marxist. (If you’re looking for a steady job in economic policy, follow Keynes.)

In my humble opinion economists must get rid of schools. We should treat our theories like ecologists treat their models: to paraphrase George Box, our models are always wrong in some respect, but they may be useful in some cases. The challenge is to identify the conditions under which they can be useful.

Why economists argue with ecologists (6): Can we price nature?

Can we express nature’s value in currency, such as dollars, euros, or yuan? I usually get one of the following three replies to this question.

The first is the hardcore ecologist:
“Most certainly not. Nature has a value in itself. Pricing nature is disrespectful to nature; it violates nature’s intrinsic value; it’s cynical and perhaps even blasphemous. Can’t we just enjoy something without putting a price tag on it? Why does everything have to be expressed in money?”

The second is the hardcore economist:
“Well, duh. People have preferences. Do you prefer an apple or an orange? Do you prefer a highway or a forest? From preference orderings we can derive the amount of compensation people would need for building that highway. So of course we can price nature. We do it every time we make a choice between nature and something else.”

The third is the pragmatic ecologist:
“I don’t like it, but if we don’t do it policy makers won’t listen to us. Economists rule the world, so to promote nature conservation we need to speak the language of economists, and that is money. So I’ll just hold my nose and price nature. But I will also remind people that the price tag does not mean that nature can be substituted for something else.”

Believe it or not, but my view is closer to the hardcore ecologist than any of the other two. So what am I doing teaching monetary valuation of the environment next June?

When we do monetary valuation of, say, a coral reef, we don’t value a coral reef. Does my wage say how much I am worth as a human being? (Boy, am I glad I never pursued that career in Dutch folk music.) No, at best it gives an indication of the value of the skills and expertise I am offering in the labor market as a teacher and researcher. Likewise, coral reef valuation aims to estimate the economic value of the goods and services provided by a coral reef, like diving tourism, coastal protection, or nursing juvenile fish. By “economic value” I mean how badly we want or need those goods and services, and how easy it would be to get them elsewhere if the coral reef disappears. That tension between how badly we want something and how easily we can get it is also called relative scarcity. Water is not scarce in The Netherlands, even though it is an essential resource. The fact that it is so easy to get makes that it has a very low market price. On the other hand, diamonds are hugely expensive, not because we need them so badly but because they are so difficult to come by. You rarely see newspaper headlines about the scarcity of people, but there is common mention of scarcity of skills or labor. The last time we put price tags on humans was during the shameful era of the slave trade. Likewise, monetary valuation does not, and should not, even pretend to price nature as such.

This view puts me at odds with the hardcore economist who argues that ethics can be fit in preference orderings and compensated for. I don’t agree with this line of reasoning. It would imply that one person can block a policy if he finds it absolutely unacceptable – after all, he would require an infinite amount of compensation in order to be left “as well off” as without the policy. In practice we would call him a protest bidder and remove his data point from our analysis. Another problem is that this line of reasoning assumes that moral objections are purely individual. Moral considerations, however, typically pretend to hold for everybody. If I think eating meat is wrong, I can allow you to order a hamburger while still condemning it. If it were a purely individual preference, for instance if I would have no quarrels with eating meat but I simply don’t like hamburgers, I would have no reason to condemn your ordering of a hamburger. So when we talk about the intrinsic value of a coral reef or a species, we have no other option but to debate it with others. The outcome of that debate may be that the majority dismisses the idea of an intrinsic value of a coral reef. But at least the argument would have its proper place in the political process, which it would not have if we tried to express it in a monetary value.

It also puts me at odds with the pragmatic ecologist. First, I find his line of reasoning insincere. If you think coral reefs are unique, unsubstitutable, and should be preserved for their own worth, just say so and don’t start using economic value as an argument of convenience. Second, economic value implies substitutability, period. If I compensate you for the loss of an environmental asset, I substitute the environmental asset by something that makes you just as well off as with the asset. So I have substituted the asset by something of similar value to you. If I cannot substitute the asset by all the wealth in the universe, then its value must be infinite: hence Michael Toman‘s characterization of Costanza’s $33 trillion paper as “a serious underestimate of infinity”. Third, valuation should be done sincerely, and with the prime goal to make sure that all relevant information is available for public decisions. If you blur the line between moral considerations and purely economic ones, you will be tempted to overstate the economic arguments because the moral ones didn’t work.

The bottom line is that when you do economic valuation, you need to define very precisely what it is you are measuring, and whether the methods you use answer the question you ask. I am deeply skeptical of measuring such notions as existence value (an economic value derived from no more than knowing something exists), because I doubt whether people understand the concept, and whether we will ever be able to distinguish it from moral considerations. But perhaps that is what the role of economists should be in this issue: to properly phrase the question, to explicitly lay out the arguments and considerations, and to quantify those considerations that can be quantified.

Why economists argue with ecologists (5): The Suzuki fallacy

I quit smoking when I was about 30 years old. It is an unhealthy habit, of course, but I also disliked the idea of being dependent on my stock of tobacco. One of the few things I miss about smoking, however, is the excuse to go outside during a break and have a fag and a chat with a few likeminded nicotinists. So occasionally I go outside with the addicts and have the chat without the fag.

I did this a while ago with an ecologist who started a long complaint about economists’ ignorance of the limits of our planet. Economists, he claimed, refer to environmental problems as ‘externalities’: they think the environment is external, i.e. irrelevant, to the economy. I tried to convince him how he misunderstood what externalities are, pointing to his sigarette. It may be his own choice to light a cigarette, or something between him and his dealer to buy a pack of cigarettes, but I also had to inhale his smoke. The damage that he thus inflicted on me was a negative externality: a cost that did not show up on his mental ‘balance sheet’. Perhaps, if he had to pay a tax for each of my lost lung cells he would have made a different choice. (You know what they say: nobody is purer than an ex-prostitute.)

I doubt whether I convinced him, but in any case his comment had me thinking. Where did he get this ludricous idea that the economic term ‘externality’ means ‘irrelevant’? After all, every introductory microeconomics book has a chapter on how externalities are a form of market failure. Then I saw this clip.

My toes still cringe when I watch this – it’s just too embarrassing. When he talks about ecosystem services:

All of the things that nature does for us, for nothing. Pollination, for example, or a forest that takes carbon dioxide out of the air and puts oxygen back in, or that holds the soil and prevent erosion.

That’s the point where I would have expected an explanation that these services are unpriced, and that we should make those services visible in the market place. For instance, by putting a price on them in public decisions, or by levying environmental taxes, or through paying the owners of the ecosystems for the services they provide. But somehow he got it into his head that

All those services that nature performs, economists call them “externalities”. And what that means is: “they got nothing to do with the economy. We don’t put a price on them, they are irrelevant.”

The speaker, David Suzuki, is a famous environmentalist. He should know his stuff, but he is making these statements without a single speck of irony, and apparently he has been doing this for years. Of course there is lots of nonsense spouted on the internet and you don’t have to react to everything, but people like my smoking ecologist listen to David Suzuki. I don’t mind criticism of economic theory, in fact I think a lot can be improved. The nice thing about interdisciplinary work is that you learn not just about the contents of other disciplines, but also their way of doing science. And this reflects back on your own discipline. But such cooperation is not helped if people start spreading this kind of prejudice and misunderstanding about one of the fields involved.