An excellent learning exercise for students of economics is to take a journal article that uses data to model the economy and then try to replicate the authors’ results. You may well be given an assignment like this in future years of your degree.
One such exercise is used on the University of Massachusetts Amherst’s doctoral programme in economics. Thomas Herndon is a student on that degree and chose to examine a well-known and highly influential paper, Growth in a Time of Debt by Carmen Reinhart then of the University of Maryland and Kenneth Rogoff of Harvard University and former chief economist of the IMF. Professors Reinhart and Rogoff used new data on 44 countries spanning about 200 years.
A key finding of their paper, published in 2010 in the American Economic Review Papers and Proceedings, is that once a country’s government debt exceeds 90% of GDP, growth rates fall considerably: the median across countries by about 1% and the mean considerably more.
The paper has been hugely influential. It has been used to justify the austerity programmes being pursued in many countries, including the UK and the eurozone. Cutting the government deficit to GDP ratio, and ultimately the government debt to GDP ratio, has been seen as a way of achieving higher growth over the longer term, and justifies the adverse effect on short-term growth from the dampening of aggregate demand.
Well, this seemed an interesting paper for Thomas Herndon to examine, and he was keen to show just how Reinhart and Rogoff’s data led to their conclusions. But try as he might, he could not replicate their results. His initial reaction was to think he had made an error, but each time he checked he came back with the same conclusion: they must have made errors in their calculations.
His supervisor at Amherst, Professor Michael Ash, after Thomas had checked and checked again, realised that something was wrong. He encouraged Thomas to write to Reinhart and Rogoff to request sight of their dataset. They duly obliged and it was then that Thomas spotted various errors. These are explained in the articles below, but the overall effect was to alter the conclusion. Although high debt may undermine growth to some extent, the effect is much less than Reinhart and Rogoff concluded, and there are several exceptions to this rule.
On 15 April 2013, Thomas, along with his supervisor, Michael Ash and his colleague, Robert Pollin, published a response to the Reinhart and Rogoff paper. In the abstract to their paper, Does High Public Debt Consistently Stifle Economic Growth? A Critique of Reinhart and Rogoff they state that:
… coding errors, selective exclusion of available data, and unconventional weighting of summary statistics lead to serious errors that inaccurately represent the relationship between public debt and GDP growth among 20 advanced economies in the post-war period. They find that when properly calculated, the average real GDP growth rate for countries carrying a public-debt-to-GDP ratio of over 90 percent is actually 2.2 percent, not –0:1 percent as published in Reinhart and Rogoff. That is, contrary to RR, average GDP growth at public debt/GDP ratios over 90 percent is not dramatically different than when debt/GDP ratios are lower.
The authors also show how the relationship between public debt and GDP growth varies significantly by time period and country. Overall, the evidence we review contradicts Reinhart and Rogoff’s claim to have identified an important stylized fact, that public debt loads greater than 90 percent of GDP consistently reduce GDP growth.
So could this be you in the future? Will you take a famous paper and, by re-examining and reworking the data, find that its conclusions are wrong? Could you end up changing the world? Exciting stuff!
Podcasts
Austerity: A Spreadsheet Error? BBC, More or Less, Tim Harford (20/4/13)
Austerity justification study ‘inaccurate’ BBC Today Programme, Robert Pollin (18/4/13)
Articles
UMass Student Exposes Serious Flaws in Harvard Economists’ Influential Study The Atlantic Wire, J.K. Trotter (18/4/13)
Shocking Paper Claims That Microsoft Excel Coding Error Is Behind The Reinhart-Rogoff Study On Debt Business Insider, Mike Konczal (16/4/13)
How a student took on eminent economists on debt issue – and won Economic Times of India (19/4/13)
Meet the 28-Year-Old Grad Student Who Just Shook the Global Austerity Movement New York Magazine, Kevin Roose (19/4/13)
An economist’s mea culpa: I relied on Reinhart and Rogoff Confessions of a Supply-Side Liberal blog, Miles Kimball (22/4/13)
The Rogoff-Reinhart data scandal reminds us economists aren’t gods The Guardian, Heidi Moore (18/4/13)
Reinhart, Rogoff… and Herndon: The student who caught out the profs BBC News Magazine, Ruth Alexander (20/4/13)
George Osborne’s case for austerity has just started to wobble The Guardian, Polly Toynbee (18/4/13)
The error that could subvert George Osborne’s austerity programme The Guardian, Charles Arthur and Phillip Inman (18/4/13)
The Excel depression Sydney Morning Herald, Paul Krugman (19/4/13)
Europe: Retreat from austerity BBC News, Gavin Hewitt (23/4/13)
Guest post by Thomas Herndon
The Grad Student Who Took Down Reinhart And Rogoff Explains Why They’re Fundamentally Wrong Business Insider, Thomas Herndon (22/4/13)
Papers
Growth in a Time of Debt NBER working paper, Carmen M. Reinhart and Kenneth S. Rogoff (January 2010)
Does High Public Debt Consistently Stifle Economic Growth? A Critique of Reinhart and Rogo ff PERI Working Paper 322, Thomas Herndon, Michael Ash and Robert Pollin (April 2013)
Questions
- What were the particular errors made by Reinhart and Rogoff?
- How has their paper been used as a basis for the design of macroeconomic policy?
- What are the limitations of using even accurate time-series data as the basis for policy measures?
- How might the work of Herndon change the direction of future macroeconomic policy?
- In his guest post in Business Insider (see link above), Herndon wrote: ‘The implication for policy is that, under particular circumstances, public debt can play a key role in overcoming a recession.’ What might this role be?
- Why might we have to be cautious in drawing policy conclusions from Herndon’s work?
Unemployment is a key macroeconomic objective for governments across the world. The unemployment rate for the UK now stands at 7.9% according to the ONS, which recorded 2.56 million people out of work. But why is unemployment of such importance? What are the costs?
The economy is already in a vulnerable state and with unemployment rising by 70,000 people between December and February 2013, the state of the economic recovery has been questioned. Indeed, following the news of the worsening unemployment data, the pound fell significantly against the dollar, suggesting a lack of confidence in the British economy.
Although the increase in the number of people out of work is concerning, perhaps of more concern should be the number of long-term unemployed. The ONS suggests that more than 900,000 have now been out of work for more than a year. Not only does this pose costs for the individual in terms of lost earnings and skills, but it also imposes costs on friends and family and the wider economy. (Click here for a PowerPoint of the first chart, which shows the percentage of unemployed people out for work longer than 12 months.)
The chief executive of the Prince’s Trust focused on the costs of youth unemployment in particular, saying:
Thousands of these young people are long-term unemployed, often facing further challenges such as poverty and homelessness. We must act now to support these young people into work and give them the chance of a better future.
(Click here for a PowerPoint of the second chart, which shows how much higher the unemployment rate is for young people aged 18 to 24 than it is for the working age population as a whole.)
Furthermore, with so many people unemployed, we are operating below full-employment and thus below our potential output. Furthermore, the longer people are out of work, the more likely it is that they will lose their skills and thus require re-training in the future or find that there are now fewer jobs available to them based on their lower skill level.
In addition to this there are monetary costs for the government through lower tax receipts, in terms of income tax, national insurance contributions and even VAT receipts. With more people unemployed, the numbers claiming various unemployment-related benefits will rise, thus imposing a further cost on the government and the taxpayer. Another cost to the government of this latest data is likely to be the expectations of the future course of the economy. Numerous factors affect business confidence and unemployment data is certainly one of them. The concern is that business confidence affects many other variables as well and until we receive more positive data, the economy recovery is likely to remain uncertain. The following articles consider this topic.
UK unemployment rise adds to pressure on Osborne’s austerity strategy The Guardian, Phillip Inman (18/4/13)
Unemployment figures are ‘worrying’, David Cameron’s spokesman says The Telegraph, Peter Dominiczak (17/4/13)
UK unemployment rises to 2.56 million BBC News (17/4/13)
Unemployment jumps to 7.9% as rise in the number of young people out of work takes figure ‘dangerously’ close to a million Mail Online, Leon Watson (17/4/13)
Unemployment up as stay-at-home mothers head back to the job-centre Independent, Ben Chu (17/4/13)
Jobs data points to finely balanced market Financial Times, Brian Groom (18/4/13)
Hugh’s review: making sense of the stats BBC News (19/4/13)
Questions
- How is unemployment measured?
- What are the costs to the individual of being unemployed?
- What are the wider non-monetary costs to society?
- Explain the main financial costs to the wider economy of a rising unemployment rate.
- Illustrate the problem of unemployment by using a production possibility frontier.
- Could there be a negative multiplier effect from a rise in unemployment?
Much has been written on Margaret Thatcher following her death at the age of 87 on April 8. But getting a calm assessment of both her time in office and her legacy is not easy. And it’s clear why: she created both stronger loyalty and stronger opposition than any other UK Prime Minister.
As economists, however, we should try to be as dispassionate as possible in assessing the effects of policies. There is always a normative question of the relative desirability of different economic outcomes – and you will have your own views on the relative importance of objectives such as economic growth, greater equality and greater social cohesion – but to determine cause and effect, or at least correlation, requires a careful examination of the evidence. Also, drawing lessons for future policy requires a careful modelling of the economy and the effects of changing economic variables.
The following articles have been selected from the hundreds that have appeared in the press in the past few days. Whilst they cannot be claimed to be totally ‘objective’, taken together they give a good overview of her economic policies and her economic legacy.
You may well have been surprised by the amount of coverage of her death and at the fervour of her supporters and critics. But this bears witness to the huge effect she had on both the political scene and on the UK economy – for good or bad.
Articles
Margaret Thatcher’s timeline: From Grantham to the House of Lords, via Arthur Scargill and the Falklands War Independent (8/4/13)
Overhauls Are Still Felt, Debated Decades Later Wall Street Journal, Charles Forelle (9/4/13)
Margaret Thatcher’s Four Ages of Monetary Policy EconoMonitor, David Smith (10/4/13)
How Mrs Thatcher smashed the Keynesian consensus The Economist (9/4/13)
Margaret Thatcher: The economy now and then BBC News, Stephanie Flanders (10/4/13)
Did Margaret Thatcher transform Britain’s economy for better or worse? The Guardian, Larry Elliott (8/4/13)
A look back at Margaret Thatcher’s economic record Washington Post, Dylan Matthews (8/4/13)
Margaret Thatcher’s legacy for business and economics—the world weighs in Quartz, Gwynn Guilford (8/4/13)
Data
Economic Data freely available online The Economics Network, see especially sites 1, 2, 3, 6 and 9
Questions
- Summarise the macroeconomic policies followed by the Thatcher government from 1979 to 1990.
- Chart economic growth, unemployment and inflation over Margaret Thatcher’s time in office. How does the performance of each of these indicators compare with the period from 1990 to 2007 and from 2008 to the present day?
- What is meant by ‘monetarism’? Did the Thatcher government follow pure monetarist policies?
- What is meant by the ‘Big Bang’ as applied to the financial sector in 1986? Assess the long-term consequences of the Big Bang.
- What elements of ‘Thatcherism’ were retained by the Labour government from 1997 to 2010?
- To what extent can the current Coalition government be described as ‘Thatcherite’?
House prices have long been an obsession with the UK media and much of the public; when they rise, homeowners feel rich, when they fall, consumer confidence dives. Following the financial crisis and subsequent recession, there has been a great deal of attention focused on the overall health of the housing market.
But the UK faces a particular problem of a sharp and growing divide in regional house prices. First time buyers in London face having to find high deposits and even then, many are unable to access mortgages. Meanwhile those in the regions can access more affordable housing, but may be reluctant to enter the market when prices are stagnant. What are the implications of this divide for the housing market and for the broader economy?
The housing market demonstrates characteristics which are typical of those for goods that are both consumable and involve capital growth; when prices rise housing is seen as a good ‘investment’ and demand increases, this in turn leads to higher prices. Conversely when values drop, demand falls and the market slumps. Markets like this are described as being prone to price bubbles.
Looking at UK house prices as a whole can, however, mask large variations across the economy; variations which can cause problems for jobseekers, for employers and for the government. Recently one of the UK’s largest mortgage lenders predicted continuing regional variance in house prices. Halifax’s figures looked at the price of housing across a number of UK towns and showed that changes seen during 2012 ranged from a 14.8 per cent rise to an 18.4 per cent fall. The biggest rise seen during the year was in Southend on Sea, in Essex, while the greatest fall was in Craigavon, in Northern Ireland. Of the ten towns with the biggest rises, eight were found in London or the south east, with Durham being the only northern town showing growth. Of the ten towns that the Halifax identified with the biggest falls, four are in Scotland, three are in the north west, one is in the north of England and one is in Northern Ireland.
Martin Ellis, housing economist at the Halifax, said:
We expect continuing broad stability in house prices nationally in 2013. The generalised north/south divide in house price performance seen during 2012 is likely to continue next year. House prices are expected to be strongest in London and the south east as this part of the country performs best in economic terms.
These disparities present a particular problem in a recession. While London and the south east show signs of economic growth, with relatively low unemployment and high levels of inward investment, many regions outside London see house prices falling further as unemployment grows. There are some exceptions – the arrival of the BBC in Salford has resulted in a sharp increase in prices there – but, in general, confidence is low outside the south east.
The articles below consider regional differences in the housing market.
Articles
House prices creep up over 2012 The Guardian, Patrick Collinson (29/1/13)
Which regions of the UK will show the biggest house price rises in the next 5 years? This is Money, Rachel Rickard Straus (17/1/13)
Figures reveal scale of regional house price divide Inside Housing, Tom Lloyd (2/1/13)
Property market gets a budget boost, so are things looking up? This is Money, Simon Lambert (21/3/13)
Help to Buy scheme could drive up house prices, says OBR The Guardian, Josephine Moulds and Jennifer Rankin (26/3/13)
London house prices outstrip 2007 peak with a 2.8% increase The Guardian, Hilary Osborne (28/3/13)
Housing market in southeast is worth £2tn Financial Times, James Pickford and Ed Hammond (1/2/13)
House prices show annual increase Evening Standard (28/3/13)
House price data
Links to house price data The Economics Network
Regional Historical House Price Data Halifax House Price Index (Lloyds Banking Group)
Questions
- Thinking about the market for owner-occupied housing, what are the factors that will determine demand? How might these explain variations in demand across different regions of the UK?
- How does the supply of housing vary across the UK?
- What would you predict about regional variations in rents?
- What is the impact of high house prices in London on first time buyers? Does this matter?
- What are the implications for the labour market of sharp variations in house prices across regions?
- Why might the Chancellor want to put in place policies to boost the housing market?
- Who gains from high house prices? Who loses? You might want to think about this in term of the life-cycle.
Inflation is measured as the percentage increase in the Consumer Prices Index (CPI) over the previous 12 months. The index is constructed from a basket of goods that is supposed to represent the buying habits of an average UK household. This basket is updated each year as tastes change and as technology moves forward. The basket contains approximately 700 items, with 180,000 individual prices collected each month.
As certain goods become more popular and trends change, the ONS have the responsibility of identifying these changes and updating the basket of goods. The CPI then looks at how the weighted average price of this basket of goods changes from one month to the next. As the CPI gives us the main measure of UK inflation, it is essential that the basket of goods used does represent current consumer demands. If the basket of goods used 20 years ago was still in place, we wouldn’t see thing like mobile phones and ipads being included. This is one sector that has seen significant growth in recent years and the basket of goods has been adapted in response. A new addition to the measure is e-books, which have seen a significant growth in popularity.
However, just as new products have been added to the CPI measure, other goods have been removed. In the most recent update, we’ve seen the removal of champagne and Freeview boxes from the basket of goods. With rapid changes in technological products, such as the ipad, kindle and e-books, products that were new additions only a few years ago are now old news, being replaced by the latest gadgets. Other changes to the basket of goods are less about reflecting consumer trends and more about making certain categories more representative, such as fruits and hot drinks.
So, can the changes in the basket of goods tell us anything about the impact of the recession on buying habits? One notable exclusion from the basket of goods is champagne sold in restaurants and bars. In an economic downturn, you’d expect luxury products to see a decline in consumption and the trend in champagne consumption certainly seems to support the theory. The trends suggest that consumers have instead switched to cheaper alternatives, with things like white rum bought from shops increasing.
Many people may look at the basket of goods and think that it doesn’t reflect what you buy in your average shop. But, the purpose of the CPI is to try to reflect the average consumer and the different items in the basket are given different weightings to give some indication of the amount spent on each good. The articles below look at the changes in the CPI basket of goods and what, if anything, we can take from it.
Inflation basket: E-books added by ONS BBC News (12/3/13)
Inflation basket – what does it say about you? Channel 4 News (12/3/13)
The fizz has fallen flat – champagne cut from inflation basket Independent, Martin Hickman (13/3/13)
E-books added to inflation basket, as champagne dropped The Telegraph, Philip Aldrick (13/3/13)
UK inflation basket: e-books in, champagne out The Guardian, Marking King (13/3/13)
Champagne tipped out of inflation basket Financial Times, Hannah Kuchler (13/3/13)
Champagne out, ebooks in as inflation basket updated Reuters (13/3/13)
Questions
- What is inflation and why is it such an important variable?
- How is the CPI calculated? Is it different from the RPI?
- What impact has technological change had on the basket of goods used to calculate the CPI?
- Can you identify any other economic or business trends from the products that are in and out of the CPI basket of goods?
- Given the importance of technology and the speed of change, do you think the review of the basket of goods should become more or less frequent?
- Has the economic downturn had any effect on the basket of goods used to calculate the CPI?
