In an introductory post, I wrote about Henri Poincaré’s attempts to model the behaviour of three bodies orbiting each other. He found that the mathematics of this problem showed that the behaviour of such a system was complex and could become unstable.
As the solar system is made up of a lot more than three bodies (one sun, eight planets, several moons, and many smaller bodies), the obvious question arising from Poincaré’s work is to ask whether the solar system is stable. Indeed, this question seems to have been one of the drivers of Poincaré’s work.
Ian Stewart has written a fascinating article which attempts to answer this question. The short answer is ‘probably not’. Luckily, the timescales involved are unlikely to worry us.
The article doesn’t require any prior knowledge of astronomy but it does use a few specialist terms such as Hohmann transfer orbits, Trojan points and Lagrange points.
23 April 2012
22 April 2012
Metronomes, people and starlings
The essence of a complex system is the interaction between its component parts. The fascination of a complex system is that apparently simple interactions can produce unexpected behaviours. Here are three examples featuring, in turn, metronomes, people and starlings.
When several metronomes are set up on a single moveable surface, such as a board on two rollers, and when they are set in out-of-phase motion, they will gradually synchronise with each other. This process is called entrainment. The scientific explanation is that the metronomes interact with each other through small vibrations in the moveable surface.
The Nobel prize-winning economist Thomas Schelling asked himself why racial segregation occurs in human populations. He could equally have asked about segregation based on nationality, caste, religion, ideology or any of the many other ways in which people identify themselves. He carried out an experiment using counters on a chess board and saw that, even with a very mild preference for the colour of a neighbouring counter, the ‘society’ of counters segregated fully into black and white. Even though individuals are rational and fairly tolerant, the societies we produce together may be neither rational nor tolerant.
Flocks of birds and shoals of fish often move in unison to create complex and beautiful patterns without any leadership and without any obvious rationale. For example, scientists have studied the behaviour of murmurations of starlings. Explanations (pdf) (and here) of their collective behaviour suggest that it may help protect the birds from predators.
Watch demonstrations of each of these three phenomena after the jump.
When several metronomes are set up on a single moveable surface, such as a board on two rollers, and when they are set in out-of-phase motion, they will gradually synchronise with each other. This process is called entrainment. The scientific explanation is that the metronomes interact with each other through small vibrations in the moveable surface.
The Nobel prize-winning economist Thomas Schelling asked himself why racial segregation occurs in human populations. He could equally have asked about segregation based on nationality, caste, religion, ideology or any of the many other ways in which people identify themselves. He carried out an experiment using counters on a chess board and saw that, even with a very mild preference for the colour of a neighbouring counter, the ‘society’ of counters segregated fully into black and white. Even though individuals are rational and fairly tolerant, the societies we produce together may be neither rational nor tolerant.
Flocks of birds and shoals of fish often move in unison to create complex and beautiful patterns without any leadership and without any obvious rationale. For example, scientists have studied the behaviour of murmurations of starlings. Explanations (pdf) (and here) of their collective behaviour suggest that it may help protect the birds from predators.
Watch demonstrations of each of these three phenomena after the jump.
21 April 2012
Franklin’s Gambit and political decision making
John Kay has written an excellent article on decision making in business and politics. His main point, which he refers to as Franklin’s Gambit, is that, even when we appear to follow a rational process for making a decision, we are often looking merely to justify a decision we have made already.
A typical rational decision-making process would be:
The Civil Service prides itself in its neutrality, and I have worked with many Civil Servants with impeccable ethics. They produce rational reports to support government decisions. Nevertheless, the conclusions of these reports almost invariably support the ideology of the government of the day, and, when the government changes, the conclusions change as well.
In business decision making, reports have an uncanny ability to reflect the views of the Chief Executive and other senior managers. On-message reports can result in promotion. Off-message reports can end careers.
In personal decision making, we often interpret new facts as confirmation of an existing bias. This extends from major decisions through to the trivial. For example,
A 2011 report (pdf) shows that there is a strong correlation between views on climate change and political ideology. If significant future man-made climate change could be proven beyond doubt, we might require expensive new government interventions and many new regulations on private sector businesses. Of course, it is not possible to prove, beyond doubt, the extent to which the climate will change over the next 50 or 100 years. Neither is it possible to prove, beyond doubt, the impact of specific changes in human behaviour. As a result, people on the right of politics, who don’t like the political implications, are mostly sceptical of climate change, while people on the left, who are more comfortable with the implications, tend to be believers.
Correspondingly, in economics, politicians on the right have decided that the solution to the current economic crisis is for government to spend less, while politicians on the left have decided that the solution is for government to spend more. Despite the fact that economists provide conflicting advice on both the causes of, and solutions to, the crisis, the political left and right agree on two things:
As a result, both left and right justify their policies mostly by pointing out the flaws in their opponents’ policies:
Richard Feynman would point out that a search for the truth, in the face of complex systems which we don’t fully understand, should involve both humility and doubt. These qualities appear to be entirely absent in our politicians and their ideologies.
A typical rational decision-making process would be:
- Scope problem
- Decide options for solving problem
- Decide evaluation criteria and relative weightings of these criteria
- Establish facts
- Evaluate options based on facts, criteria and weightings
- Make decision.
- Scope problem
- Make decision
- Decide options for solving problem
- Establish facts
- Decide evaluation criteria and weightings which support decision made in step 2
- Evaluate options based on facts, criteria and weightings
- Confirm decision made in step 2.
The Civil Service prides itself in its neutrality, and I have worked with many Civil Servants with impeccable ethics. They produce rational reports to support government decisions. Nevertheless, the conclusions of these reports almost invariably support the ideology of the government of the day, and, when the government changes, the conclusions change as well.
In business decision making, reports have an uncanny ability to reflect the views of the Chief Executive and other senior managers. On-message reports can result in promotion. Off-message reports can end careers.
In personal decision making, we often interpret new facts as confirmation of an existing bias. This extends from major decisions through to the trivial. For example,
- When we cast a vote in an important election, we may choose the candidate with the same background or ideology as ourselves irrespective of the merits of the debate during the election campaign. Alternatively, we persuade ourselves that the candidate who offers us the biggest cut in taxes, or increase in benefits, or the ability to buy our council house at a knock-down price, has the best policies for the broader community
- When a player from our favourite football team dives in the penalty area, we see an obvious penalty. However, when a player from an opposing team dives in the same situation, we see a cheat.
A 2011 report (pdf) shows that there is a strong correlation between views on climate change and political ideology. If significant future man-made climate change could be proven beyond doubt, we might require expensive new government interventions and many new regulations on private sector businesses. Of course, it is not possible to prove, beyond doubt, the extent to which the climate will change over the next 50 or 100 years. Neither is it possible to prove, beyond doubt, the impact of specific changes in human behaviour. As a result, people on the right of politics, who don’t like the political implications, are mostly sceptical of climate change, while people on the left, who are more comfortable with the implications, tend to be believers.
Correspondingly, in economics, politicians on the right have decided that the solution to the current economic crisis is for government to spend less, while politicians on the left have decided that the solution is for government to spend more. Despite the fact that economists provide conflicting advice on both the causes of, and solutions to, the crisis, the political left and right agree on two things:
- The correct policies are clear and beyond doubt
- The correct policies are the ones which are consistent with their existing ideological beliefs.
As a result, both left and right justify their policies mostly by pointing out the flaws in their opponents’ policies:
- The right says that the left prioritises jobs over debt. Increasing government spending in the hope of creating jobs will increase the debt further. This will lead to disaster. Look at Greece!
- The left says that the right prioritises debt over jobs. Reducing government spending in the hope of reducing the debt will increase unemployment further. This will increase the level of unemployment benefit payments, so might not even reduce the debt (or the annual deficit). Austerity leads to more austerity!
Richard Feynman would point out that a search for the truth, in the face of complex systems which we don’t fully understand, should involve both humility and doubt. These qualities appear to be entirely absent in our politicians and their ideologies.
19 April 2012
More on economics models
When you are trying to diagnose and cure a problem in a business or a government organisation, business models are extremely useful. There are all sorts of ways of modelling a business. However, they can be divided into two main classes: top-down models and bottom-up models. Top-down models aim to give a management perspective on a problem while bottom-up models give a shop-floor perspective.
Economists use a similar distinction between top-down macroeconomic models and bottom-up microeconomic models. A key issue in both business analysis and economics is the relationship between the top-down and bottom-up models, and the level of consistency between them. Business analysts have debated these issues for many years, so what does business analysis have to contribute to the current modelling debates in economics?
Most people have no interest in, or experience with, either business models or economic models, so I’m going to use a more familiar set of models to make some relevant points, although I learned these lessons through developing business models.
Let’s start with a top-down view of the geography of the earth. Here is a photograph taken from Apollo 17. It’s known as the Blue Marble.
At this scale and perspective, we can see that the earth is round, and we can identify feature such as continents, the sea, the snow-covered poles and large areas of cloud. A second model, at a similar scale, might help us understand that the earth orbits the sun with its polar axis at an angle of around 23 degrees. This model would allow us to explain the seasons of the year.
When we change scale to look at the earth in greater detail, we move to atlases and maps. As these models show a round object on a flat surface, we need to use projections such as Mercator, Gall-Peters and Mollweide to produce these models. Projections distort the relative size and position of different objects on the earth. Different projections distort the earth in different ways. At this scale, and subject to the rules of any specific projection, we can use these models to see the relative size and positions of countries, and large features such as mountain ranges, large lakes and the biggest rivers.
When we change scale again to look at an individual country, the distortions of different projections become less pronounced, particularly for small countries. At this scale, we can use different maps to see more detail. For example, we might see geographical and political boundaries, towns and cities, and major road and rail networks. Even if we are unfamiliar with a country, we can ask interesting questions which can help expand our knowledge: why are the states in the north-east of the USA often small while the states elsewhere are much larger; why do some states have regular boundaries while others have jagged boundaries? If we are not familiar with the distortions in the map, we may misunderstand the picture we are viewing: is Alaska really an island off the south-west coast of Texas; and what happened to Canada and Mexico?
Finally, when we change scale again, we can use street maps to navigate around a single town or city. We can also use highly stylised maps to navigate tube and subway networks. In these latter maps, we may even lose a sense of the physical distance between stations. However, these maps are still useful in helping us to select the correct train line and to understand when we need to change from one line to another.
What general rules can we take from these geographical models which could also be applied to business and economic models?
In general, business analysts have recognised these characteristics in their use of models. Perhaps that’s because their customers hold them to account in providing useful answers to specific questions, and because they insist on models that reflect the facts as they understand them. In contrast, the debates in economics seems to focus more on the correctness and consistency of economic models rather than their usefulness in solving problems or in explaining problems and solutions to non-experts.
Economists use a similar distinction between top-down macroeconomic models and bottom-up microeconomic models. A key issue in both business analysis and economics is the relationship between the top-down and bottom-up models, and the level of consistency between them. Business analysts have debated these issues for many years, so what does business analysis have to contribute to the current modelling debates in economics?
Most people have no interest in, or experience with, either business models or economic models, so I’m going to use a more familiar set of models to make some relevant points, although I learned these lessons through developing business models.
Let’s start with a top-down view of the geography of the earth. Here is a photograph taken from Apollo 17. It’s known as the Blue Marble.
The Blue Marble
At this scale and perspective, we can see that the earth is round, and we can identify feature such as continents, the sea, the snow-covered poles and large areas of cloud. A second model, at a similar scale, might help us understand that the earth orbits the sun with its polar axis at an angle of around 23 degrees. This model would allow us to explain the seasons of the year.
When we change scale to look at the earth in greater detail, we move to atlases and maps. As these models show a round object on a flat surface, we need to use projections such as Mercator, Gall-Peters and Mollweide to produce these models. Projections distort the relative size and position of different objects on the earth. Different projections distort the earth in different ways. At this scale, and subject to the rules of any specific projection, we can use these models to see the relative size and positions of countries, and large features such as mountain ranges, large lakes and the biggest rivers.
When we change scale again to look at an individual country, the distortions of different projections become less pronounced, particularly for small countries. At this scale, we can use different maps to see more detail. For example, we might see geographical and political boundaries, towns and cities, and major road and rail networks. Even if we are unfamiliar with a country, we can ask interesting questions which can help expand our knowledge: why are the states in the north-east of the USA often small while the states elsewhere are much larger; why do some states have regular boundaries while others have jagged boundaries? If we are not familiar with the distortions in the map, we may misunderstand the picture we are viewing: is Alaska really an island off the south-west coast of Texas; and what happened to Canada and Mexico?
Map of US States
Finally, when we change scale again, we can use street maps to navigate around a single town or city. We can also use highly stylised maps to navigate tube and subway networks. In these latter maps, we may even lose a sense of the physical distance between stations. However, these maps are still useful in helping us to select the correct train line and to understand when we need to change from one line to another.
What general rules can we take from these geographical models which could also be applied to business and economic models?
| Rule | Description |
|---|---|
| 1 | Models can be developed at different scales and with different perspectives |
| 2 | All models are simplifications of reality |
| 3 | Models should be judged as useful rather than correct. Models which distort reality can still be useful as long as the reader understands the distortion and its limitations |
| 4 | It is vital that any model helps you answer specific questions. It is often better to develop several simple models, with different perspectives, to answer different questions. A model which helps you understand the seasons of the year may not help you find your way round the London tube network, and vice versa |
| 5 | It is essential to develop models which provide insights for the layman into the complexities associated with the questions he is asking, and into the answers to these questions. This does not preclude the use of expert-only models but such models cannot, and should not, be used to communicate with non-experts |
| 6 | A model presented as a diagram is normally easier for a layman to understand than an equivalent verbal description |
| 7 | Different people may need and expect to see the same situation from different scales and perspectives, so multiple models may be needed to communicate with different audiences |
| 8 | It is not always possible to develop top-down models simply by combining bottom-up models. You cannot tell that the world is round from a city street map. |
In general, business analysts have recognised these characteristics in their use of models. Perhaps that’s because their customers hold them to account in providing useful answers to specific questions, and because they insist on models that reflect the facts as they understand them. In contrast, the debates in economics seems to focus more on the correctness and consistency of economic models rather than their usefulness in solving problems or in explaining problems and solutions to non-experts.
09 April 2012
Paul Krugman and economics models
During my quest to understand the mental models used by economists, I came across a fascinating 20 year-old article by Paul Krugman. The article’s title is ‘How I Work’ and it outlines Krugman’s basic rules for conducting interesting research. The reason the article is fascinating to me is that it provides a rare insight into how a leading economist thinks about economics rather than merely what he thinks.
The article includes a number of interesting insights into Krugman’s background. For example, he makes the following observation about what distinguishes the way he thinks, and his attitude to models, from most other economists.
The article includes a number of interesting insights into Krugman’s background. For example, he makes the following observation about what distinguishes the way he thinks, and his attitude to models, from most other economists.
| Most young economists today enter the field from the technical end. Originally intending a career in hard science or engineering, they slip down the scale into the most rigorous of the social sciences. The advantages of entering economics from that direction are obvious: one arrives already well trained in mathematics, one finds the concept of formal modeling natural. It is not, however, where I come from. My first love was history; I studied little math, picking up what I needed as I went along. |
|---|
| Paul Krugman |
Economics and models
The development of mental models is one of the most important ways through which we make sense of the world around us. That’s true of everything from the earth orbiting the sun to the internal workings of a jet engine, and from the maps that help us navigate to our political systems. When we have good models, we call them scientific and, when we don’t, we think in terms of belief and ideology. When we share a common model, it is easy to debate how to improve the model, and when we don’t we tend to struggle to make any advances.
In order to work out what is wrong with economics, and economists, I wanted to understand the mental models that economists use to drive their thinking. What does the economy look like? Who are the main participants e.g. banks, businesses, households? How do they interact with each other?
When I looked for this type of insight, one of the first surprises I found was that economists seem to make little use of diagrams. Although this might seem trivial, it means that it is very difficult for a layman to envisage how economists picture the economy, why they expect a particular policy change to improve the economy, or how the view of one economist differs from that of another.
A verbal description is the next best option. The economics profession set up the Institute for New Economic Thinking (INET) to promote novel ideas following the advent of the current economic crisis. It held an inaugural conference, attended by many of the world’s leading economists, in April 2010. At this conference, Joseph Stiglitz gave an excellent presentation (including 23 slides with, of course, no diagrams) where he discussed many of the limitations of the models and methodologies used by mainstream economists prior to the crisis. He also proposed some areas for research to improve these models. Here are just a few key points.
Stiglitz began by discussing some of the mainstream economic beliefs which had turned out to be wrong. One of these was incredible.
Now, bubbles have been known since Tulip Mania in the 1630s, and the Internet bubble burst only a few years before the current crisis. As a result, this statement, on its own, seems to be sufficient evidence to discredit the entire mainstream economics profession.
Stiglitz then discussed some of the assumptions that mainstream economists use in their models. These include an assumption that all people are identical and can be modelled as a single representative agent, and a further assumption of rational expectations which suggests that the representative agent always behaves rationally and with perfect information on the state of the economy. Again, these statements seem to discredit the entire profession. As Stiglitz indicated, if there is a single representative agent then how do financial markets work e.g. who sells to whom, who lends to whom, how can bankruptcies happen, who causes a run on the stock market? Most importantly, these assumptions preclude the current crisis.
One of Stiglitz’s main overall points was that there is no possibility of interactions between agents in these models. He concluded that one of the biggest modelling challenges for the profession is the inclusion of various types of interaction. These include regulation and control interactions as well as the transactional interactions which drive markets.
One of my initial observations on this blog concerned double pendulums. A single pendulum is the equivalent of the economic vision of a rational agent with very predictable behaviour. A single pendulum has perfect information on the influence of gravity on its behaviour. However, when two pendulums interact, the resultant system can produce unpredictable and unstable behaviour. It seems that the vast majority of the economics profession is oblivious to this type of behaviour.
Taking these points together, the pre-crisis economics profession resembles a religious cult more than a group of professional experts investigating the behaviour of a complex system. At the very least, they come across as a closed community with limited ability to draw analogies, and inspiration, from similar fields of study such as meteorology. As a pseudo-scientific endeavour, pre-crisis mainstream economics resembles a modern equivalent of alchemy.
| The image of the world around us, which we carry in our head, is just a model. Nobody in his head imagines all the world, government or country. He has only selected concepts, and relationships between them, and uses those to represent the real system. |
|---|
| Jay Wright Forrester |
In order to work out what is wrong with economics, and economists, I wanted to understand the mental models that economists use to drive their thinking. What does the economy look like? Who are the main participants e.g. banks, businesses, households? How do they interact with each other?
When I looked for this type of insight, one of the first surprises I found was that economists seem to make little use of diagrams. Although this might seem trivial, it means that it is very difficult for a layman to envisage how economists picture the economy, why they expect a particular policy change to improve the economy, or how the view of one economist differs from that of another.
| A picture is worth a thousand words, except in economics. |
|---|
| Jamie |
A verbal description is the next best option. The economics profession set up the Institute for New Economic Thinking (INET) to promote novel ideas following the advent of the current economic crisis. It held an inaugural conference, attended by many of the world’s leading economists, in April 2010. At this conference, Joseph Stiglitz gave an excellent presentation (including 23 slides with, of course, no diagrams) where he discussed many of the limitations of the models and methodologies used by mainstream economists prior to the crisis. He also proposed some areas for research to improve these models. Here are just a few key points.
Stiglitz began by discussing some of the mainstream economic beliefs which had turned out to be wrong. One of these was incredible.
| There is no such thing as a bubble. |
|---|
| The mainstream economics profession |
Now, bubbles have been known since Tulip Mania in the 1630s, and the Internet bubble burst only a few years before the current crisis. As a result, this statement, on its own, seems to be sufficient evidence to discredit the entire mainstream economics profession.
Stiglitz then discussed some of the assumptions that mainstream economists use in their models. These include an assumption that all people are identical and can be modelled as a single representative agent, and a further assumption of rational expectations which suggests that the representative agent always behaves rationally and with perfect information on the state of the economy. Again, these statements seem to discredit the entire profession. As Stiglitz indicated, if there is a single representative agent then how do financial markets work e.g. who sells to whom, who lends to whom, how can bankruptcies happen, who causes a run on the stock market? Most importantly, these assumptions preclude the current crisis.
One of Stiglitz’s main overall points was that there is no possibility of interactions between agents in these models. He concluded that one of the biggest modelling challenges for the profession is the inclusion of various types of interaction. These include regulation and control interactions as well as the transactional interactions which drive markets.
One of my initial observations on this blog concerned double pendulums. A single pendulum is the equivalent of the economic vision of a rational agent with very predictable behaviour. A single pendulum has perfect information on the influence of gravity on its behaviour. However, when two pendulums interact, the resultant system can produce unpredictable and unstable behaviour. It seems that the vast majority of the economics profession is oblivious to this type of behaviour.
Taking these points together, the pre-crisis economics profession resembles a religious cult more than a group of professional experts investigating the behaviour of a complex system. At the very least, they come across as a closed community with limited ability to draw analogies, and inspiration, from similar fields of study such as meteorology. As a pseudo-scientific endeavour, pre-crisis mainstream economics resembles a modern equivalent of alchemy.
06 April 2012
What do we mean by ‘hot’?
One of the unexpected benefits of having worked on projects to design and implement government policy is a greater appreciation for words. We take words for granted and we don’t often give them much thought. That’s a mistake.
Take the word ‘hot’ (no, not that ‘hot’). ‘Hot’ has been in the news recently, in the UK, as a result of the budget. The problem is that there are different rates of VAT for food that is ‘hot’ and food that is ‘not hot’.
For most foods this is not a problem. Fish & chips are ‘hot’ so VAT applies. Sandwiches are ‘not hot’ so VAT does not apply.
What about pasties though? Pasties are prepared freshly in bakeries and then offered for sale. However, the pasties may cool down before they are sold. When is a pasty ‘hot’ and when is it ‘not hot’? If you visit a bakery and there are some pasties fresh from the oven should you buy the pasties and pay VAT, or should you wait half an hour until the pasties are ‘not hot’ and save yourself some money? What do we mean by ‘hot’ anyway? In summer, the ambient temperature will be higher so pasties will cool down more slowly. A ‘not hot’ pasty in summer will be ‘hotter’ than the same pasty in winter. Should VAT apply more in summer than in winter?
Of course, this is complete nonsense, but it arises because someone decided it would be a good idea to have different VAT rules for ‘hot’ and ‘not hot’ food. We elect these people so it is really our fault.
When governments make laws using terms such as ‘hot’, there are always examples at the boundary where the distinction is dubious. This means that these examples are then ‘unfair’. ‘Unfair’ is another word which takes on a life of its own when associated with government policy. ‘Incentives’ is a further example.
Take income tax. If we introduced income tax today, we might create a few simple rules. A flat tax is clearly ‘unfair’ so we might settle for a fixed non-taxable allowance for each individual plus a fixed percentage of all income above that point. Some politicians would then decide that this was still ‘unfair’ while other politicians would decide that the system could be improved by introducing ‘incentives’. Over time, politicians would introduce new rules corresponding to their views of ‘fairness’ and ‘incentives’. Unfortunately, ‘fair’ taxes often result in ‘perverse incentives’, and taxes which promote ‘incentives’ are often ‘unfair’. Redistribution is ‘fair’ but discourages wealthy people from working. Reducing the tax on capital gains is an ‘incentive’ to invest but is ‘unfair’ to those whose income comes only from their labour.
Over time, by introducing these new rules, the politicians would create a tax system which was not particularly ‘fair’ and which did not do much for ‘incentives’. However, it would be very complex. The same politicians would then react to the problems in this complex system by introducing more rules to correct the anomalies arising from the ‘unintended unfairness’ and ‘perverse incentives’. This would result in even more complexity but would still not be very ‘fair’, nor would it produce more effective ‘incentives’. What it would do is to spawn an industry of accountants who would offer to help reduce tax bills by exploiting the many loopholes in the system. Of course, the only people who could afford these services would be large businesses and rich individuals. And that would not be ‘fair’.
‘Fair’ is a word whose meaning is in the eye of the beholder. Child Benefit is a universal benefit. For some reason, that is deemed to be ‘fair’ even though it involves paying government money to millionaires who don’t need it. In most other contexts, using government money to make rich people even richer would be deemed ‘unfair’. Yet, in the case of Child Benefit, we make an exception. Perversely, the current centre-right government has plans to stop paying Child Benefit to millionaires while the left-wing opposition protests that this is ‘unfair’. Imagine if the policy were being implemented in reverse. Suppose that Child Benefit were not currently paid to millionaires and that the government proposed to extend it to millionaires in the middle of our extended recession/depression. I am certain that this would be seen as ‘unfair’ on the Left, so we have two polar opposite policies both of which are seen as ‘unfair’ by the same people.
Actually, there is a germ of logic in the Child Benefit criticisms. The government needed a practical mechanism to decide who should be eligible to receive the benefit. It decided to use the income tax system. The income tax system taxes individuals rather than ‘families’. As a result, the proposed new rules discriminate against ‘families’ with one ‘high’ wage earner and a stay-at-home non earner. ‘Families’ with two ‘lower’ wage earners can avoid losing the benefit even when, in some cases, their combined ‘family’ income is higher than the income of the ‘high’ wage ‘families’.
You’ll see that I have used quotes for ‘family’ and for ‘higher’ and ‘lower’ wages. That’s because these words have their own issues. For example, the ‘lower’ wage earners in my example have incomes which are substantially ‘higher’ than the average national income. As for ‘family’, well that would need an entire post to itself.
Tim Harford wrote a funny article on the subject of the pasty tax this week. He also mentioned last year’s Mirrlees Review (and at BBC and The Guardian) which put forward proposals for a more rational tax system.
These issues are not specific to the UK. Gregory Mankiw wrote an article in The New York Times last month on the problems of defining ‘ordinary income’ and ‘capital gains’ ‘fairly’ in the US.
Take the word ‘hot’ (no, not that ‘hot’). ‘Hot’ has been in the news recently, in the UK, as a result of the budget. The problem is that there are different rates of VAT for food that is ‘hot’ and food that is ‘not hot’.
For most foods this is not a problem. Fish & chips are ‘hot’ so VAT applies. Sandwiches are ‘not hot’ so VAT does not apply.
What about pasties though? Pasties are prepared freshly in bakeries and then offered for sale. However, the pasties may cool down before they are sold. When is a pasty ‘hot’ and when is it ‘not hot’? If you visit a bakery and there are some pasties fresh from the oven should you buy the pasties and pay VAT, or should you wait half an hour until the pasties are ‘not hot’ and save yourself some money? What do we mean by ‘hot’ anyway? In summer, the ambient temperature will be higher so pasties will cool down more slowly. A ‘not hot’ pasty in summer will be ‘hotter’ than the same pasty in winter. Should VAT apply more in summer than in winter?
Of course, this is complete nonsense, but it arises because someone decided it would be a good idea to have different VAT rules for ‘hot’ and ‘not hot’ food. We elect these people so it is really our fault.
When governments make laws using terms such as ‘hot’, there are always examples at the boundary where the distinction is dubious. This means that these examples are then ‘unfair’. ‘Unfair’ is another word which takes on a life of its own when associated with government policy. ‘Incentives’ is a further example.
Take income tax. If we introduced income tax today, we might create a few simple rules. A flat tax is clearly ‘unfair’ so we might settle for a fixed non-taxable allowance for each individual plus a fixed percentage of all income above that point. Some politicians would then decide that this was still ‘unfair’ while other politicians would decide that the system could be improved by introducing ‘incentives’. Over time, politicians would introduce new rules corresponding to their views of ‘fairness’ and ‘incentives’. Unfortunately, ‘fair’ taxes often result in ‘perverse incentives’, and taxes which promote ‘incentives’ are often ‘unfair’. Redistribution is ‘fair’ but discourages wealthy people from working. Reducing the tax on capital gains is an ‘incentive’ to invest but is ‘unfair’ to those whose income comes only from their labour.
Over time, by introducing these new rules, the politicians would create a tax system which was not particularly ‘fair’ and which did not do much for ‘incentives’. However, it would be very complex. The same politicians would then react to the problems in this complex system by introducing more rules to correct the anomalies arising from the ‘unintended unfairness’ and ‘perverse incentives’. This would result in even more complexity but would still not be very ‘fair’, nor would it produce more effective ‘incentives’. What it would do is to spawn an industry of accountants who would offer to help reduce tax bills by exploiting the many loopholes in the system. Of course, the only people who could afford these services would be large businesses and rich individuals. And that would not be ‘fair’.
‘Fair’ is a word whose meaning is in the eye of the beholder. Child Benefit is a universal benefit. For some reason, that is deemed to be ‘fair’ even though it involves paying government money to millionaires who don’t need it. In most other contexts, using government money to make rich people even richer would be deemed ‘unfair’. Yet, in the case of Child Benefit, we make an exception. Perversely, the current centre-right government has plans to stop paying Child Benefit to millionaires while the left-wing opposition protests that this is ‘unfair’. Imagine if the policy were being implemented in reverse. Suppose that Child Benefit were not currently paid to millionaires and that the government proposed to extend it to millionaires in the middle of our extended recession/depression. I am certain that this would be seen as ‘unfair’ on the Left, so we have two polar opposite policies both of which are seen as ‘unfair’ by the same people.
Actually, there is a germ of logic in the Child Benefit criticisms. The government needed a practical mechanism to decide who should be eligible to receive the benefit. It decided to use the income tax system. The income tax system taxes individuals rather than ‘families’. As a result, the proposed new rules discriminate against ‘families’ with one ‘high’ wage earner and a stay-at-home non earner. ‘Families’ with two ‘lower’ wage earners can avoid losing the benefit even when, in some cases, their combined ‘family’ income is higher than the income of the ‘high’ wage ‘families’.
You’ll see that I have used quotes for ‘family’ and for ‘higher’ and ‘lower’ wages. That’s because these words have their own issues. For example, the ‘lower’ wage earners in my example have incomes which are substantially ‘higher’ than the average national income. As for ‘family’, well that would need an entire post to itself.
Tim Harford wrote a funny article on the subject of the pasty tax this week. He also mentioned last year’s Mirrlees Review (and at BBC and The Guardian) which put forward proposals for a more rational tax system.
These issues are not specific to the UK. Gregory Mankiw wrote an article in The New York Times last month on the problems of defining ‘ordinary income’ and ‘capital gains’ ‘fairly’ in the US.
05 April 2012
How did economists get it so wrong?
In 2009, Paul Krugman wrote an article for The New York Times entitled How Did Economists Get It So Wrong? It is an excellent summary of mainstream economic thinking from Keynes to the present day (albeit from a very US-oriented perspective). It is also very good on the deficiencies of the economics profession in predicting the current economic crisis. I particularly like his analogies about baby-sitting and the price of ketchup.
04 April 2012
Wanted – useful economists
There seem to be few hard and fast rules in economics. Take the concept of division of labour. We are all better off when we each take a specialist role and then trade with each other. This works well almost everywhere for all manner of goods and services. However, it doesn’t work when asking and answering big questions on economics.
Suppose I want to know the likely impact on inflation of current government policies. As it happens, I have been asking this question and doing some internet research. Economists are the specialists in this area and they have been working on this question for some time. According to economists, the answer is that hyperinflation is likely; or mild inflation; or no inflation; or prolonged deflation. The economics professional does not speak with a single voice on this question. I am left with the task of deciding for myself which, if any, of these answers is correct. Of course, in order to do this, I will first need to teach myself economics to the level of a Nobel prize-winner and then work through the pros and cons of the arguments for each answer. I may be some time.
I’m being a little unfair here, but only a little, so I have a dilemma. In order to make any progress, I need to use the knowledge of ‘the best’ economists, but it’s not at all clear to me which economists are ‘the best’. I need some criteria.
I have set out some criteria, including basic reasoning, below. I have not made any attempt at balance in these criteria. I do not know enough about the many schools of economic thought to achieve political, ideological or methodological balance.
I’ve been looking for economists who meet at least some of these criteria for a while. Here is my initial list of the economists from whom I’m hoping to learn:
As most of these economists have blogs and use Twitter, it’s easy to find their views. Some of them have boisterous arguments with their ideological and methodological opponents, so it’s easy to find alternative views as well.
There are lots of financial blogs on the internet. Here is Time magazine’s list of the 25 best financial blogs.
Suppose I want to know the likely impact on inflation of current government policies. As it happens, I have been asking this question and doing some internet research. Economists are the specialists in this area and they have been working on this question for some time. According to economists, the answer is that hyperinflation is likely; or mild inflation; or no inflation; or prolonged deflation. The economics professional does not speak with a single voice on this question. I am left with the task of deciding for myself which, if any, of these answers is correct. Of course, in order to do this, I will first need to teach myself economics to the level of a Nobel prize-winner and then work through the pros and cons of the arguments for each answer. I may be some time.
I’m being a little unfair here, but only a little, so I have a dilemma. In order to make any progress, I need to use the knowledge of ‘the best’ economists, but it’s not at all clear to me which economists are ‘the best’. I need some criteria.
I have set out some criteria, including basic reasoning, below. I have not made any attempt at balance in these criteria. I do not know enough about the many schools of economic thought to achieve political, ideological or methodological balance.
| Criterion | Description |
|---|---|
| Mainly macroeconomics | Economics is made up of top-down macroeconomics and bottom-up microeconomics. The questions I want to answer seem to be mostly macroeconomic questions. |
| Prediction track record | Economists who predicted the current crisis are more likely to have mental models that are consistent with the facts. Of course, they could have predicted the crisis through luck, so a longer track record is desirable. |
| Recognition of failings | Economists who have acknowledged openly the economics profession’s failings are more likely to be open to identifying problems and making improvements. |
| Good communications | Economists who talk in plain English are easier to understand than those who use abstract jargon. |
| Flow diagrams | Economists who use diagrams to demonstrate the flows of goods, services, information and money between the various stakeholders in the economy, are likely to be easier to understand than those who use only words. |
| Complex systems | Economists who use the language of complex systems are more likely to fit my own beliefs. |
| Trial and error | In the face of a complex system which demonstrates unpredictable behaviour, economists who advocate the use of experimentation, trial and error, and controlled experiments, are more likely to fit my own beliefs. |
I’ve been looking for economists who meet at least some of these criteria for a while. Here is my initial list of the economists from whom I’m hoping to learn:
| Name | Country | Website/Blog | Wikipedia | Other | |
|---|---|---|---|---|---|
| Ha-Joon Chang | South Korea | Website/Blog | Wikipedia | ||
| Tim Harford | UK | Website/Blog | Wikipedia | More or Less | |
| John Kay | UK | Website/Blog | Wikipedia | ||
| Steve Keen | Australia | Website/Blog | Wikipedia | ||
| Richard Koo | Taiwan | Wikipedia | |||
| Paul Krugman | USA | Website/Blog | Wikipedia | ||
| Paul Ormerod | UK | Website/Blog | Wikipedia | ||
| Joseph Stiglitz | USA | Website/Blog | Wikipedia |
As most of these economists have blogs and use Twitter, it’s easy to find their views. Some of them have boisterous arguments with their ideological and methodological opponents, so it’s easy to find alternative views as well.
There are lots of financial blogs on the internet. Here is Time magazine’s list of the 25 best financial blogs.
03 April 2012
The Pleasure of Finding Things Out
One of the main complications in economics is finding the correct balance between scientific (or empirical) thinking and decision-making, and philosophical (or moral or political) thinking and decision-making.
The current economic crisis has shown us that the economics profession doesn’t know enough about how the economy works to help us define clear rules for how the banking system should work, or how a multi-country currency like the Euro should work, in order to prevent these things from threatening the stability of the entire economic system. Perhaps a few economists know enough to help us develop appropriate rules but how would we go about identifying them?
In practice, we determine the rules for these systems by electing politicians, and their advisors, to set the rules on our behalf. However, if economists don’t know the appropriate rules then why should we expect politicians to be able to set such rules? Also, if we want stable banking and currency systems then what logic should we use in casting our votes in elections?
Some people vote on a moral basis: people should be more self-reliant, or society should be fairer, or we should be more careful with the environment. Other people vote for selfish reasons: they want a promised tax cut or benefit increase. Yet more people vote simply to get rid of an incompetent or corrupt government and replace it with something (anything) different. Perhaps, we can rely on the wisdom of crowds. More likely, we just have no choice but to rely on this type of decision making.
Nobody votes for anyone who has a scientific understanding of how banks and currencies actually work. Of course, that’s because no-one seems to have this understanding. Nevertheless, it’s difficult to understand why we don’t appear to think it’s important to know how these things actually work. There is no relationship between a moral choice, such as a vote for a fairer society, and an understanding of relatively apolitical truths relating to banking systems and currencies. How do we expect these things to work out well?
Somehow, the balance between scientific thinking and philosophical thinking feels wrong. Perhaps, politicians are better salesmen than scientists? Perhaps, scientists confuse the rest of us by using complex jargon and mathematics? Perhaps we just don’t trust people who look like an archetypal ‘nutty professor’? Perhaps we find it difficult to distinguish ‘scientific method’ and ‘scientists’? Perhaps science is just too much effort?
I don’t have heroes but, if I did, one would be Richard Feynman. Feynman was a Nobel prize-winning physicist. He was also a good talker, he used plain English rather than jargon, and he didn’t look like a nutty professor. He understood that scientific method was more important than the ego of any scientist. He was a great ambassador for the virtues of scientific thinking such as curiosity, open-mindedness, rigour, perseverance, humour and humility in the face of observed practical evidence.
Feynman was featured in a number of BBC documentaries. In particular, he discussed his views on scientific thinking in The Pleasure of Finding Things Out. He discussed the pleasure of finding things out about a remote country in Asia called Tannu Tuva in The Last Journey of a Genius. Some of Feynman’s greatest hits are also featured in a number of shorter YouTube videos.
Watch a selection of Feynman’s thoughts after the jump.
The current economic crisis has shown us that the economics profession doesn’t know enough about how the economy works to help us define clear rules for how the banking system should work, or how a multi-country currency like the Euro should work, in order to prevent these things from threatening the stability of the entire economic system. Perhaps a few economists know enough to help us develop appropriate rules but how would we go about identifying them?
In practice, we determine the rules for these systems by electing politicians, and their advisors, to set the rules on our behalf. However, if economists don’t know the appropriate rules then why should we expect politicians to be able to set such rules? Also, if we want stable banking and currency systems then what logic should we use in casting our votes in elections?
Some people vote on a moral basis: people should be more self-reliant, or society should be fairer, or we should be more careful with the environment. Other people vote for selfish reasons: they want a promised tax cut or benefit increase. Yet more people vote simply to get rid of an incompetent or corrupt government and replace it with something (anything) different. Perhaps, we can rely on the wisdom of crowds. More likely, we just have no choice but to rely on this type of decision making.
Nobody votes for anyone who has a scientific understanding of how banks and currencies actually work. Of course, that’s because no-one seems to have this understanding. Nevertheless, it’s difficult to understand why we don’t appear to think it’s important to know how these things actually work. There is no relationship between a moral choice, such as a vote for a fairer society, and an understanding of relatively apolitical truths relating to banking systems and currencies. How do we expect these things to work out well?
Somehow, the balance between scientific thinking and philosophical thinking feels wrong. Perhaps, politicians are better salesmen than scientists? Perhaps, scientists confuse the rest of us by using complex jargon and mathematics? Perhaps we just don’t trust people who look like an archetypal ‘nutty professor’? Perhaps we find it difficult to distinguish ‘scientific method’ and ‘scientists’? Perhaps science is just too much effort?
I don’t have heroes but, if I did, one would be Richard Feynman. Feynman was a Nobel prize-winning physicist. He was also a good talker, he used plain English rather than jargon, and he didn’t look like a nutty professor. He understood that scientific method was more important than the ego of any scientist. He was a great ambassador for the virtues of scientific thinking such as curiosity, open-mindedness, rigour, perseverance, humour and humility in the face of observed practical evidence.
Feynman was featured in a number of BBC documentaries. In particular, he discussed his views on scientific thinking in The Pleasure of Finding Things Out. He discussed the pleasure of finding things out about a remote country in Asia called Tannu Tuva in The Last Journey of a Genius. Some of Feynman’s greatest hits are also featured in a number of shorter YouTube videos.
Watch a selection of Feynman’s thoughts after the jump.
02 April 2012
Economics, seismology and meteorology
Economics and seismology have some similarities. Both subjects involve the study of complex systems which are stable for much of the time, but which are capable of causing great damage when they become unstable. Both subjects are in their infancy – neither has the capability to prevent catastrophic instabilities and neither has the capability to predict such instabilities.
So why do we seem to have a problem with economists but not seismologists.
Meteorology also has major limitations. Again, it involves a complex system which is stable for much of the time, but which can cause massive destruction when it becomes unstable. Weather forecasters can make accurate predictions for a few days ahead but are less good over longer periods. They can predict major events such as hurricanes but can’t predict their precise paths. They can’t prevent hurricanes from occurring and they can’t change their paths when they represent a major threat to life and property.
So why do we seem to have a problem with economists but not meteorologists.
One answer is that seismology and meteorology study complex natural systems whereas the economy is a complex system with a man-made design. Our expectations of what seismologists and meteorologists can achieve are limited by our shared understanding that we are merely trying protect ourselves from forces which are more powerful than us. Our expectation of economists is that they should help us design and control the economy, rather than just try to understand it and forecast major instabilities. We expect economists to be able to run before they can walk.
A second answer relates to the frequency of instabilities. Earthquakes and hurricanes occur many times a year, whereas major economic depressions may happen only once or twice in each lifetime. We expect earthquakes and hurricanes, but are surprised when the economy becomes unstable.
A third answer follows on from the first two. Our common understanding of the limitations of seismology means that we can take collective actions to protect ourselves against earthquakes:
No such common understanding seems to exist regarding what reliable services we can expect from economists, or whether the rest of us would find such services useful. Imagine that meteorologists always predicted that tomorrow’s weather would be very similar to today’s weather, and imagine that many of them said that their models showed that hurricanes could not occur. They would be correct much of the time but that service would not be useful. This is compounded by the apparent inability of the economics profession to speak with a single voice on anything. As a result, when a major economic crisis occurs, we are each left to our own devices to determine the appropriate course of action, and that action tends to involve panic.
A final answer relates to politics. We ask our politicians, and their economic advisers, to design an optimal economy for us. An honest politician would point out the limitations of our current abilities to do this. Of course, no-one would vote for a politician, or listen to an economic adviser, who expressed this type of humility. We are nevertheless surprised when successive sets of politicians and economists fail to live up to their unrealistic promises.
We have only ourselves to blame.
So why do we seem to have a problem with economists but not seismologists.
Meteorology also has major limitations. Again, it involves a complex system which is stable for much of the time, but which can cause massive destruction when it becomes unstable. Weather forecasters can make accurate predictions for a few days ahead but are less good over longer periods. They can predict major events such as hurricanes but can’t predict their precise paths. They can’t prevent hurricanes from occurring and they can’t change their paths when they represent a major threat to life and property.
So why do we seem to have a problem with economists but not meteorologists.
One answer is that seismology and meteorology study complex natural systems whereas the economy is a complex system with a man-made design. Our expectations of what seismologists and meteorologists can achieve are limited by our shared understanding that we are merely trying protect ourselves from forces which are more powerful than us. Our expectation of economists is that they should help us design and control the economy, rather than just try to understand it and forecast major instabilities. We expect economists to be able to run before they can walk.
A second answer relates to the frequency of instabilities. Earthquakes and hurricanes occur many times a year, whereas major economic depressions may happen only once or twice in each lifetime. We expect earthquakes and hurricanes, but are surprised when the economy becomes unstable.
A third answer follows on from the first two. Our common understanding of the limitations of seismology means that we can take collective actions to protect ourselves against earthquakes:
- Design buildings to withstand the shocks of a major earthquake
- Design walls to hold back related tsunamis
- Design early warning systems to flash messages about impending earthquakes and tsunamis into television and radio broadcasts
- Educate the general population on how to protect themselves during an earthquake
- Design and implement disaster recovery plans.
No such common understanding seems to exist regarding what reliable services we can expect from economists, or whether the rest of us would find such services useful. Imagine that meteorologists always predicted that tomorrow’s weather would be very similar to today’s weather, and imagine that many of them said that their models showed that hurricanes could not occur. They would be correct much of the time but that service would not be useful. This is compounded by the apparent inability of the economics profession to speak with a single voice on anything. As a result, when a major economic crisis occurs, we are each left to our own devices to determine the appropriate course of action, and that action tends to involve panic.
A final answer relates to politics. We ask our politicians, and their economic advisers, to design an optimal economy for us. An honest politician would point out the limitations of our current abilities to do this. Of course, no-one would vote for a politician, or listen to an economic adviser, who expressed this type of humility. We are nevertheless surprised when successive sets of politicians and economists fail to live up to their unrealistic promises.
We have only ourselves to blame.
01 April 2012
Economics 101: Hayek and Keynes
One of the consequences of the entanglement of the empirical and political aspects of economics is that the subject has created a number of god-like figures. Certain economists are treated almost as though they were infallible by the followers of the political ideologies which they inspired.
As these economists are all long dead, it is interesting to speculate about what they would say regarding the followers who interpret their words and turn those interpretations into political actions. I doubt that they would be pleased.
Irrespective of the merits of their original ideas, Adam Smith (1723-1790) and Karl Marx (1818-1883) seem to have suffered particularly badly in this respect. However, it is probably the later pair of Friedrich Hayek (1899-1992) and John Maynard Keynes (1883-1946) who exert most influence in modern economics and politics. Hayek is seen as a founding father of many free-market and libertarian ideas championed on the Right of modern politics, while Keynes has the equivalent position regarding the mixed economy championed on the Left.
EconStories has made a couple of videos humanising Hayek and Keynes by depicting them as rappers and as flawed individuals. The videos are entertaining and informative. They also introduce some of the key economic terms used in debates on the current economic crisis e.g. boom and bust, crony capitalism, paradox of thrift, liquidity trap and malinvestment.
I’ve been looking at a number of quotes attributed to Hayek and Keynes. My feeling is that they’d both be sceptical about many of the simplistic answers advocated in their names.
Watch two Hayek and Keynes raps after the jump.
As these economists are all long dead, it is interesting to speculate about what they would say regarding the followers who interpret their words and turn those interpretations into political actions. I doubt that they would be pleased.
Irrespective of the merits of their original ideas, Adam Smith (1723-1790) and Karl Marx (1818-1883) seem to have suffered particularly badly in this respect. However, it is probably the later pair of Friedrich Hayek (1899-1992) and John Maynard Keynes (1883-1946) who exert most influence in modern economics and politics. Hayek is seen as a founding father of many free-market and libertarian ideas championed on the Right of modern politics, while Keynes has the equivalent position regarding the mixed economy championed on the Left.
EconStories has made a couple of videos humanising Hayek and Keynes by depicting them as rappers and as flawed individuals. The videos are entertaining and informative. They also introduce some of the key economic terms used in debates on the current economic crisis e.g. boom and bust, crony capitalism, paradox of thrift, liquidity trap and malinvestment.
I’ve been looking at a number of quotes attributed to Hayek and Keynes. My feeling is that they’d both be sceptical about many of the simplistic answers advocated in their names.
| The curious task of economics is to demonstrate to men how little they really know about what they imagine they can design. |
|---|
| Friedrich Hayek |
| We shall not grow wiser before we learn that much that we have done was very foolish. |
|---|
| Friedrich Hayek |
| The progress of the natural sciences in modern times has, of course, so much exceeded all expectations that any suggestion that there may be some limits to it is bound to arouse suspicion. |
|---|
| Friedrich Hayek |
| If economists could manage to get themselves thought of as humble, competent people, on a level with dentists, that would be splendid. |
|---|
| John Maynard Keynes |
| Economists set themselves too easy, too useless a task if, in tempestuous seasons, they can only tell us that, when the storm is past, the ocean is flat again. |
|---|
| John Maynard Keynes |
| The difficulty lies not so much in developing new ideas as in escaping from old ones. |
|---|
| John Maynard Keynes |
Watch two Hayek and Keynes raps after the jump.
Economics 101: The Story of Economics
The BBC radio programme The Story of Economics provides a clear and simple introduction to the subject for a layman like me. I like it because it is presented by a non-economist (economists are part of the set of problems I’m trying to solve) and because it doesn’t try to present a black or white view.
The programme has three half-hour episodes, each dealing with a different perspective on the subject:
My objective is to understand the empirical aspects of economics. However, one of the problems is that it’s very difficult to disentangle the empirical and political aspects. The economy is a complex system where there are few black and white ‘provable’ rules. It is very difficult to run controlled experiments. As soon as an empirical economist makes a policy recommendation, it becomes almost impossible to distinguish the empirical economist from the politician.
Yet there are some economic outcomes, such as the collapse of a currency or a banking system, which are in no-one’s political interest. The fact that such catastrophic outcomes still occur, or threaten to occur, suggests to me that our empirical understanding is fairly limited.
The programme has three half-hour episodes, each dealing with a different perspective on the subject:
- Gods: economics as a morality tale
- Cogs: economics as a clockwork machine
- Monsters: economics as a study of human behaviour.
My objective is to understand the empirical aspects of economics. However, one of the problems is that it’s very difficult to disentangle the empirical and political aspects. The economy is a complex system where there are few black and white ‘provable’ rules. It is very difficult to run controlled experiments. As soon as an empirical economist makes a policy recommendation, it becomes almost impossible to distinguish the empirical economist from the politician.
Yet there are some economic outcomes, such as the collapse of a currency or a banking system, which are in no-one’s political interest. The fact that such catastrophic outcomes still occur, or threaten to occur, suggests to me that our empirical understanding is fairly limited.
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