Tag: herd effects

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Evolving Economics

The linked article below, by Evan Davis, assesses the state of economics. He argues that economics has had some major successes over the years in providing a framework for understanding how economies function and how to increase incomes and well-being more generally.

Over the last few decades, economists have …had an influence over every aspect of our lives. …And during this era in which economists have reigned, the world has notched up some marked successes. The reduction in the proportion of human beings living in abject poverty over the last thirty years has been extraordinary.

With the development of concepts such as opportunity cost, the prisoners’ dilemma, comparative advantage and the paradox of thrift, economics has helped to shape the way policymakers perceive economic issues and policies.

These concepts are ‘threshold concepts’. Understanding and being able to relate and apply these core economic concepts helps you to ‘think like an economist’ and to relate the different parts of the subject to each other. Both Economics (10th edition) and Essentials of Economics (8th edition) examine 15 of these threshold concepts. Each time a threshold concept is used in the text, a ‘TC’ icon appears in the margin with the appropriate number. By locating them in this way, you can see their use in a variety of contexts.

But despite the insights provided by traditional economics into the various problems that society faces, the discipline of economics has faced criticism, especially since the financial crisis, which most economists did not foresee.

Even Davis identifies two major shortcomings of the discipline – both beginning with ‘C’. ‘One is complexity, the other is community.’

In terms of complexity, the criticism is that economic models are often based on simplistic assumptions, such as ‘rational maximising behaviour’. This might make it easier to express the models mathematically, but mathematical elegance does not necessarily translate into predictive accuracy. Such models do not capture the ‘messiness’ of the real world.

These models have a certain theoretical elegance but there is now an increasing sense that economies do not evolve along a well-defined mathematical path, but in a far more messy way. The individual players within the economy face radical uncertainty; they adapt and learn as they go; they watch what everybody else does. The economy stumbles along in a process of slow discovery, full of feedback loops.

As far as ‘community’ is concerned, people do not just act as self-interested individuals. Their actions are often governed by how other people behave and also by how their own actions will affect other people, such as family, friends, colleagues or society more generally.

And the same applies to firms. They will be influenced by various other firms, such as competitors, trend setters and suppliers and also by a range of stakeholders – not just shareholders, but also workers, customers, local communities, etc. A firm’s aim is thus unlikely to be simple short-term profit maximisation.

And this broader set of interests translates into policy. The neoliberal free-market, laissez-faire approach to policy is challenged by the desire to take account of broader questions of equity, community and social justice. However privately efficient a free market is, it does not take account of the full social and environmental costs and benefits of firms’ and consumers’ actions or a fair distribution of income and wealth.

It would be wrong, however, to say that economics has not responded to these complexities and concerns. The analysis of externalities, income distribution, incentives, herd behaviour, uncertainty, speculation, cumulative causation and institutional values and biases are increasingly embedded in the economics curriculum and in economic research. What is more, behavioural economics is becoming increasingly mainstream in examining the behaviour of consumers, workers, firms and government. We have tried to reflect these developments in successive editions of our four textbooks.

Article

Questions

  1. Write a brief defence of traditional economic analysis (i.e. that based on the assumption of ‘rational economic behaviour’).
  2. What are the shortcomings of traditional economic analysis?
  3. What is meant by ‘behavioural economics’ and how does it address the concerns raised in Evan Davis’ article?
  4. How is herd behaviour relevant to explaining macroeconomic fluctuations?
  5. Identify various stakeholder groups of an energy company. What influence are they likely to have on the company’s behaviour?
  6. In an era of social media, web-based information and e-commerce, why might it be necessary to rethink the concept of GDP and its measurement?
  7. What is meant by an efficient stock market? Why may the stock market not be efficient?
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Predicting the stock market: it’s normally too late

With worries about Greek exit from the eurozone, with the unlikelihood of further quantitative easing in the USA and the UK, with interest rates likely to rise in the medium term, and with Chinese growth predicted to be more moderate, many market analysts are forecasting that stock markets are likely to fall in the near future. Indeed, markets are already down over the past few weeks. Since late April/early May, the FTSE is down 4.5%; the German DAX index is down 7.0%; the French CAC40 index is down 6.9%; and the US Dow Jones index is down 2.3%. But does this give us an indication of what is likely to happen over the coming months?

If stock markets were perfectly efficient, then all possible information about the future will already have been taken into account and will all be reflected in current share prices. It would be impossible to ‘get ahead of the game’.

It is only if market participants have imperfect information and if you have better information than other people that you can are likely to predict correctly what will happen. Even then, the markets might be buffeted by random and hence unpredictable shocks.

Some people correctly predicted things in the past: such as crashes or booms. But in many cases, this was luck and their subsequent predictions have proved to be wrong. When financial advisers or newspaper columnists give advice, they are often wrong. If they were reliably right, then people would follow their advice and markets would rapidly adjust to their predictions.

If Greece were definitely to exit the euro, if interest rates were definitely to rise in the near future, if it became generally believed that stock markets were overvalued, then stock markets would probably fall. But these things may not happen. After all, people have been predicting a rise in interest rates from their ultra-low levels for many months – and it hasn’t happened yet, and may not happen for some time to come – but it may!

If you want to buy shares, you might just as well buy them at random – or randomly sell any you already have. As Tetlock says, quoted in the Nasdaq article:

“Even the most astute observers will fail to outperform random prediction generators – the functional equivalent of dart-throwing chimps.”

And yet, people do believe that they can predict what is going to happen to stock markets – if not precisely, then at least roughly. Are they deluded, or can looking calmly at likely political and economic events put them one step ahead of other people who perhaps behave more reactively and emotionally?

Bond rout spells disaster for stock markets as global credit kraken awakens The Telegraph, John Ficenec (14/6/15)
Comment: Many imponderables for markets The Scotsman, Bill Jamieson (14/6/15)
How Ignoring Stock Market Forecasts Will make you a better investor Forbes, Ky Trang Ho (6/6/15)
The Predictions Racket Nasdaq, AdviceIQ, Jason Lina (21/5/15)

Questions

  1. Why may a return of rising interest rates lead to a ‘meltdown in equity prices’? Why might it not?
  2. Why have bond yields fallen dramatically since 2008?
  3. Why are bond yields rising again now and what significance might this have (or have had) for equity markets?
  4. Why may following the crowd often lead to buying high and selling low?
  5. Is there an asymmetry between buying and selling behaviour in stock markets?
  6. Will ignoring stock market forecasts make people better investors?
  7. “The stock market prices suggest that investors believe both the Federal Reserve and the Bank of England are bluffing about raising interest rates. That may be so, but it is an extremely risky game of chicken for investors to play.” Explain and discuss.