What is ‘Evolution’? What is ‘Complexity’? [and How does it inform the study of policymaking?]

by Paul Cairney, Professor of Politics and Public Policy, University of Stirling. Originally published at http://paulcairney.blogspot.co.uk on 13 May 2013

There is a long history in the social sciences of using the natural sciences as a source of comparison. Much of the comparison is based on little more than the (often very useful) metaphor. There is now an equally important but shorter history of trying to draw more direct parallels; to say that this process in a social system is directly comparable to a process in a natural or living system. The study of evolution provides the potential for that sort of direct comparison, and we can find the use of terms such as ‘complexity’ (or ‘complex systems’) employed partly to that end. However, there are two major obstacles to this sort of direct comparison (and indeed to the use of evolution-based metaphors):

1. We may not agree about the meaning of evolution. For example, when it is used loosely in everyday language, ‘evolution’ tends to refer to a very long term, gradual process of change. However, evolution can also refer to the idea of ‘punctuated equilibrium’ in which long spells of gradual change are interrupted by relatively short but profound bursts of activity and change. Consequently, the study of evolution is instantly confusing because it can refer to the *opposite of* and/ or the *same thing as* revolution. There are also some other sources of potential confusion about, for example, the nature of evolution (does it necessarily refer to advancement?) and the nature of ‘selection’ (do species simply respond blindly to their environments or help create them?).

2. Some people have really ruined evolution for the rest of us. We can blame so-called ‘social-Darwinism’ for the racist/ sexist idea that some people are more evolved than others. In other words, ‘evolution’ comes with a lot of baggage when we apply it to social science discussions.

This sort of confusion can be found in the study of public policy where evolution can refer to a wide range of things, including:

  • the cumulative, long-term development of policy solutions;
  • major disruptions in the way that policy makers think about, and try to solve, policy problems;
  • the maintenance *or* radical reform of policy-making institutions;
  • ‘emergent’ behaviour within complex systems
  • the trial-and-error strategies adopted by actors, such as policy entrepreneurs, when adapting to their environment
  • the coming together of multiple factors to create the conditions for major policy change (which can be a creative, ‘window of opportunity’ style process, or a destructive, failure-related ‘perfect storm style process).

This range of understandings may not put us off evolutionary discussions completely, but it shows us that we should be super-clear about our meaning of evolution when we seek to make these sorts of comparisons with evolution in nature.

I suppose this has been a roundabout way for me to advertise the fact that I have just published a journal article about this very topic (if you can’t access it, I can send you a *non-final* version or you can try getting it through a free trial). It compares the most prominent theories of politics and policymaking which draw on references to evolution in different ways. For example:

Multiple Streams Analysis (Kingdon) – uses the term ‘policy primeval soup’ to suggest that, although policymaker attention may lurch from one problem to another, problems will not be addressed until policy solutions have evolved sufficiently within a policy community and policymakers have the motive and opportunity to adopt them. ‘Evolution’ describes the *slow progress* of an idea towards acceptability within the policy community.

Punctuated Equilibrium theory (Baumgartner and Jones) – suggests that that ‘incremental’ policy change in most cases is accompanied by ‘seismic’ change in a small number of cases – an outcome consistent with ‘power laws’ found in the natural and social worlds. Kingdon’s picture of slow progress producing partial mutations is replaced by Baumgartner and Jones’ *fast, disruptive, pure mutation* (in some cases).

Then there is complexity theory, which I have discussed in my blog here. The relevance to a discussion of evolution is that complexity theory may help us understand processes in which people, institutions and their environments are interacting constantly to produce rather unpredictable outcomes (or, at least, outcomes may ‘emerge’ locally, in the absence of central control). This might be broken down into three steps:

  1. Institutions, as sets of rules and norms, represent ways for people to retain certain ideas and encourage particular forms of behaviours.
  2. Complex systems represent (partly) a large number of overlapping and often interdependent institutions.
  3. New behaviours and rules arise from the interaction between multiple institutions and the actors involved.

In other words, different ‘worlds’ are in constant collision, producing new ways of thinking and behaviour that ‘emerge’ from these interactions. They are then passed down through the generations, but in an imperfect way, allowing new forms of thinking and behaviour to emerge.

To describe these processes as ‘evolutionary’, we really need to use the language of evolution – variation, selection and retention – to describe and explain outcomes. The idea in the natural world is that living things want to do at least two things: (1) pass on their genes; (2) cooperate with others to secure resources and share them out to their kith and kin. The idea in the political world is a bit different and perhaps a bit of a stretch, but here goes:

  • The equivalent of passing on genes is passing on ‘memes’, or ideas (beliefs, ways of thinking – as described in the 70s by Richard Dawkins before he moved onto God).
  • ‘Variation’ refers to the different rules adopted by different social groups to foster the collective action required to survive.
  • ‘Selection’ describes the interaction between people and their environments; particular environments may provide an advantage to some groups over others and encourage certain behaviours (or, at least, some groups may respond by adapting their behaviour to their environment).
  • ‘Retention’ describes the ways in which people pass on their genes (memes) to ensure the reproduction of their established rules (we might call them ‘institutions’).

The key difference in the study of evolution and policymaking is the idea of passing on memes through the generations. We think of passing on genes through the generations as a process that takes hundreds, thousands or millions of years. Passing on memes through the ‘policy generations’ is more like the study of fruit flies (months), viruses or bacteria (days or weeks). In other words, ways of thinking, and emerging behaviour, change constantly as people interact with each other, articulating different beliefs and rules and producing new forms of thinking, rules and behaviour as they interact. Big jumps in ways of thinking may be associated with key generational shifts, but that can take place, for example, as one generation of scientists retires or, more quickly still, one generation of experts is replaced (within government circles) by another.

Complexity theory may be used to capture, describe and explain that sort of interaction on a grand scale. We can zoom in to see individuals interacting with each other, or zoom out to observe mass behaviour and the sorts of outcomes that emerge from them. For me, this means that the field is wide open when it comes down to research methods. If we are interested in people understanding this complex process of interaction, we can study those individuals using interviews and/ or various forms of observation. If we are interested in the whole system, we might adopt mathematical models and computer simulations. There is nothing to stop us combining such methods (and more) if we avoid the sort of people that adhere slavishly to one fixed understanding of the world and, therefore, one method to help us understand it.

I don’t hold out much hope of this sort of discussion capturing the public imagination. However, the chances are that this sort of discussion of evolution (and its relationship to complexity theory) is taking place in a wide range of disciplines without much exchange between them. So, if you see a blog like this written by someone else in some other field, please let me know.

Cairney, P. (2013). What is evolutionary theory and how does it inform policy studies?. Policy & Politics, 41(2), 279-298.
http://www.ingentaconnect.com/content/tpp/pap/2013/00000041/00000002/art00008

A wider debate on how Europe shapes British policy making is now needed

Janice Morphet
Janice Morphet

This article was originally posted at the LSE’s EUROPP – European Politics and Policy blog on 2 May 2013

The UK’s forty-year relationship with the EU and its predecessors has seen a significant integration of EU policies into the UK’s institutional culture. Janice Morphet looks at how the UK has implemented EU legislation in recent decades, finding that there has been little public discussion of their potential implications. She argues that it may now be time to promote a more engaged discussion and debate on how the EU shapes UK public policy.

Since 1972, it has been difficult to have a conversation about the pooling of the UK’s powers within the EU. While the lead up to joining the EU saw a strong and coordinated campaign for membership, the 1975 referendum on ‘staying in’ may have created a continuing uncertainty in the relationship which can be characterised as ‘out of sight, out of mind’. But over the following forty years, why has this position persisted? And what effects has it had?

The UK joined the EU with its head not with its heart. Changes in world trade and the growing European market meant a re-evaluation of the UK’s position. Whilst an Atlanticist longing remained for some British politicians, it was clear that the US defined the UK as being the friend in the EU not the partner outside it. Once a member, the UK retained its post-war position, assuming leadership and policy transfer without revising its focus of attention or its negotiating methods to suit the emerging institutional culture. Whitehall absorbed the processes of developing EU policy within its own internal methods, welcoming praise from other member states for internal coordination and overlooking their cultural practices of negotiation.

Whilst Margaret Thatcher, as Prime Minister, was associated with exposing the public sector to competition – resulting in ‘privatisation’, this was not in the 1979 Conservative manifesto. Rather it was a GATT agenda that the Labour Cabinet had agreed in 1976 and an issue where EU member states then negotiated individually. But it was Jacques Delors, then President of the European Commission, who understood how the objectives of ‘ever closer union’ and Thatcher’s marketisation could be brought together, through the means of the creation of the Single Market.

Delors laid his plans skilfully. Firstly the process of developing the Single Market was put in the hands of the UK Commissioner, Arthur Cockfield, a former Secretary of State for Trade. Secondly, he gave him full backing to roam over the whole of the EU’s policies in support of an integrated approach. Thirdly, Delors adopted an artificial date – of 1992 – for the single market to be implemented – a date that coincided with the UK’s Presidency of the Council.

In 1986, the UK was in the midst of opening the public sector to competition. The Single Market was regarded as a vehicle to enhance the potential for both competiton and expansion. The UK failed to recognise that the single market would require wider regulatory reform crossing many areas of public policy. These included the environment, population mobility, transfer of professional qualifications, transport, employment rights, finance and regulatory reform. As Cockfield found, the Prime Minister did not understand the nature of the UK’s EU membership and its implications. Further, he found that during the negotiations, Parliament was kept at a distance, knew little and seemed to care less about the Single European Act, in ways that fundamentally alarmed him.

It was no surprise, then, to find that the implications of the Single Market came as a jolt to Whitehall and Westminster. The old assumptions, for example, that the UK’s environmental standards were equal to or better than those in other member states took a sharp knock as EU legislation was poorly implemented or misunderstood. The Whitehall machine responded with a language of distancing and denial. As Whitehall and Westminster were involved in discussions on the increasing swathes of legislation required to implement the Single Market, there was talk of this being advisory or aspirational rather than agreed commitments.

So the UK was hoist on its own petard as further areas of policy were pooled but no open discussions about the potential implications of Treaties and their subsequent programmes of legislation were undertaken in the media – a topic that is a current consideration for the House of Commons Select Committee on European Scrutiny. A major interest for Westminster and Whitehall became how could the pooled policy agreements be implemented under the cover of domestic policy? A number of policy orphans appeared – such as the creation of the Government Offices of the Regions to give a nod towards applying the principle of subsidiarity introduced in the Treaty on European Union in 1992. This was followed by their abolition in 2010 as the subsidiarity principle reached its full expression in the 2009 Lisbon Treaty.

In the EU, the programmed approach is important, giving enough ‘wriggle room’ for all member states to implement any reforms required over more than one government’s term. This approach has been adopted since 1992 in the UK with the introduction of Spending Reviews that mirror EU budget periods and are useful policy vehicles for incorporating the ‘new’ without openly discussing their provenance. Nevertheless, the UK still characterises its approach through machinery of government steps rather EU flows. As Gisela Stuart MP recently said in evidence to the EU Scrutiny Select Committee ‘whenever the Government comes in, you wipe the slate clean and you start anew. The European Commission has no similar process’.

So what effects has this longstanding approach had? Although a key issue is a lack of public understanding of the current UK’s pooled policy objectives and agendas within the EU, there is a more disquieting concern that there is a lack of appreciation of these processes across the wider academic and policy communities in civil society. It is hard to have discussions on those policies which the UK develops and implements through its EU membership if there is no common discourse that stretches back over 40 years. Ministers and civil servants are negotiating today what will be implemented in 2020, whilst tomorrow they will be discussing how to implement what was agreed five or ten years ago. Unlike other member states, these jobs are not regarded as necessary stages in a high-flying career but a specialist backwater. Is it time to make good this deficit and engage in these policy discussions from an informed perspective?

Janice Morphet’s new book How the EU shapes British public policy is available with 20% discount from www.policypress.co.uk

DEBATE: Is it time to put the dream of elected mayors to bed?

The Policy & Politics Blog features debates from recent issues. An extract is below, then please click on the link at the end to download the full article. Policy & Politics is the leading journal in the field of public policy with an enviable reputation for publishing peer-reviewed papers of the highest quality .

Policy & Politics Debates, October 2012

Alex Marsh

In May 2012, ten of England’s major urban local authorities held referendums on moving to a model of governance focused on a directly elected mayor. Only one city – Bristol – voted in favour. Elsewhere the proposal was rejected relatively decisively, albeit with a generally low voter turnout.

David Cameron’s coalition government has emphasised large urban areas as drivers of economic growth. It has championed elected mayors as the mechanism for delivering the leadership necessary to capitalise on the potential of our cities. The outcome of the referendum therefore represents a significant setback.

May’s referendums are only the latest instalment in this saga. The leitmotif is central government enthusiasm finding limited resonance at local level. Given that we have had several unsuccessful attempts to (re)invigorate the idea of elected mayors for England, is it now time to put the idea to bed?

Read the rest of this article by downloading the pdf (free).

Call for panels for the First International Conference on Public Policy (ICPP)

Over the past thirty years, public policy research has grown as an academic field of study in many countries. Coming from a range of disciplines in the social sciences and humanities, including political science, public administration, geography, sociology, economics and law among others, this research has helped develop our understanding on the many phenomena related to public policy-making by governments.  The first International Conference on Public Policy (ICPP) will join together all of the researchers who work on public policy and their different approaches and topics, and will take place at Science Po Grenoble, 26-28 June 2013.

The conference is sponsored by six Research Committees of the International Political Science Association which work on different aspect of public policy, and by the Public Policy sections of the European Consortium for Political Research and the American Political Science Association.

During this conference, opportunities will be provided for both junior and senior researchers from a variety of disciplines to present and discuss new research, theoretical, conceptual and methodological insights and empirical findings through a system of panels and workshops intended and will also involve conference speakers and plenary discussions.

The conference call for participation is structured in two steps. The first step is a call for panel proposals with a deadline of 1st November 2012. This will be followed by a general call for papers with a deadline of 31th of January 2013.

The organising committee are inviting proposals for panels for this conference. A Panel can have from 1 to 3 sessions and each session can have 4 papers which can be presented. Panel proposals can be on any specific topic; theoretical, methodological or empirical are welcome.

To propose a panel, please send an abstract of no more than 300 words to icpp2013@sciencesconf.org providing a title and explaining the scientific interest of the Panel. Paper details are not necessary at this point.

More details on the conference and timelines can be found on the ICPP 2013 website.

The results of the panel adjudication will be released on November 15 and details of each accepted panel posted to the ICPP website on December 1 along with a call for papers.

Policy & Politics free article

The following article from the latest issue of Policy & Politics has been made free for the rest of August:

Welcome relief or indecent subsidy? The implications of wage top-up schemes

Abstract:

A key policy response to the downward pressure on wages of the lowest-paid workers in the developed economies of the capitalist world has been the introduction of meanstested cash transfer schemes by which to top up low wages. Findings from a study of the experiences of the beneficiaries of a particular scheme (the United Kingdom’s Working Tax Credit) suggest that, although schemes may serve to relieve the poverty of low-paid workers and their families, the extent to which they promote the accessibility of ‘decent work’ is ambiguous.

View the pdf now.

DEBATE: ‘Capitalism works only when the rewards are seen to be shared’

Policy & Politics Debates, July 2012
Sarah Ayres, Associate Editor, School for Policy Studies, University of Bristol

The most recent ‘debates’ articles for Policy & Politics are written by Stewart Lansley (Visiting Fellow, University of Bristol) and Professor Kevin Doogan (Centre for Urban and Public Policy Research, University of Bristol).

Lansley charts the growth of inequality under capitalism since the 1970s. He contends that ‘the proceeds of economic growth have been increasingly colonised by a small financial and business elite’ and that this trend is unsustainable. The forces driving higher levels of inequality remain in place and this, it is argued, makes economies increasingly unstable and prone to crisis. You can read the article, ‘Capitalism works only when the rewards are seen to be shared’ for free here.

Doogan responds by suggesting that appeals for a ‘nicer capitalism’ are perhaps unrealistic and instead solutions need to be found in broad societal transformations, rather than incremental reforms of the capitalism system. His article, ‘A fairer capitalism?’ is also now available for free here.

To find out more about Policy & Politics, please visit our website.

DEBATE: A Big Society needs an active state

 

The Policy & Politics Blog features debates from recent issues . An extract is below, then please click on the link at the end to download the full article. Policy & Politics is the leading journal in the field of public policy with an enviable reputation for publishing peer-reviewed papers of the highest quality .

DEBATE: A Big Society needs an active state

Helen Sullivan

The state has become unfashionable again in the United Kingdom (UK). Following a brief flirtation with it as an agent for good under New Labour, the current financial crisis and the ideological preferences of the coalition government mean that the state is now regarded at best as an outmoded way of meeting needs, and at worst a block to citizen action, business entrepreneurship and efficient service delivery… Read the rest of this article by downloading the pdf (free).

DEBATE: A Beveridge report for the 21st century? The implications of self-directed support for future welfare reform

The Policy & Politics Blog features debates from recent issues . An extract is below, then please click on the link at the end to download the full article. Policy & Politics is the leading journal in the field of public policy with an enviable reputation for publishing peer-reviewed papers of the highest quality .

DEBATE: A Beveridge report for the 21st century? The implications of self-directed support for future welfare reform

Jon Glasby, Simon Duffy, Catherine Needham

In the early 21st century, elements of the English welfare state are in the middle of a ‘transformation’ process based on the concepts of personalisation and self-directed support (HM Government, 2007; Glasby and Littlechild, 2009; Carr, 2010; Needham, 2010). Beginning in adult social care, these approaches seek to recast users of state welfare away from being passive recipients of prepurchased services towards a situation where they are active citizens with a right to control and shape their own support. Central to this agenda has been the concept of direct payments (pioneered by disabled people’s organisations and developing in the United Kingdom from the mid-1980s onwards) and personal budgets (developed from 2003 onwards by a national social innovation network known as In Control)… Read the rest of this article by downloading the pdf (free).

Obama and the Biracial Factor: The Battle for a New American Majority

Andrew Jolivette, author of Obama and the Biracial Factor: The Battle for a New American Majority looks at the ideological battle that is at stake in the current US election campaign:

The battle for a new American political and ideological majority continues in 2012. The upcoming election for President of the United States is opening a floodgate of rhetoric laced with divisive political campaigns, racial bigotry, and a call for a politics of hope rather then despair. On Tuesday January 24th, 2012 in his third state of the union address, President Obama in response to critics and in conversation with U.S. voters presented a vision that will unite Americans, he presented the same message as he did in 2008—a message of hope!

Obama and the Biracial Factor, published today, argues that Mr. Obama was able to build a diverse coalition of supporters that represents the changing demographic and ideological diversity of the United States. The project and contributors ask if President Obama will be able to maintain this new political coalition by using an ideology of inclusion. A primary assertion in the book is that his biracial background equips him with a treasure chest of lived experiences that allow him to speak to many different people. Over the past three years the Obama administration has faced an onslaught of obstructionism and underlying rhetoric from he is “not one of us” to “he is a European socialist”. The current election campaign is a clear indication of the ideological battle that is at stake. On the republican side, consider the following recent comments and incidents:

Newt Gingrich has called Obama the “greatest food stamp” President in U.S. history.

The Lawrence Journal-World was sent an email that Mike O’Neal, speaker of Kansas’ House of Representatives forwarded to House Republicans that referred to President Obama and a Bible verse that says “Let his days be few” and calls for his children to be without a father and his wife to be widowed.

Republican Governor of Arizona, Jan Brewer was recently photographed pointing her finger directly into the face of President Obama when he arrived at the Arizona airport

Mitt Romney has said the President’s call for the “Buffet Rule” (a policy that would require millionaires to pay the same tax rate as their secretaries, 30% instead of the 15% they currently pay) is about a “politics of envy” and class division.

The irony of these assaults on President Obama and his agenda to level the playing field for middle class Americans is that the Republican primary has dramatically impacted GOP frontrunner Mr. Romney whose negative rating among independent voters went from 22% viewing him in a negative or somewhat negative light in November to a 42% negative or somewhat negative view of him in the latest polls. Obama who was down 13% points to Romney in November among independent voters, now leads Romney by 8% points in new polls. This is due in part to what we argue in Obama and the Biracial Factor, America is seeking a new ideology that unifies people rather then dividing them.

As the 2012 re-election campaign begins for Mr. Obama it is important to take note of his comments to the American people in the state of the union address last week. They are a stark contrast to conservative attacks that call for him to “get the hell out of the country” as Rep Allen West (R) from Florida said in comments to the media in recent days. Calling again upon his biracial background as a source for talking about what brings different people together, Obama, in contrast to both Romney and Gingrich, made himself look more presidential when he said to congress and the American people that:

“Those of us who’ve been sent here to serve can learn a thing or two from the service of our troops.  When you put on that uniform, it doesn’t matter if you’re black or white; Asian, Latino, Native American; conservative, liberal; rich, poor; gay, straight.  When you’re marching into battle, you look out for the person next to you, or the mission fails.  When you’re in the thick of the fight, you rise or fall as one unit, serving one nation, leaving no one behind…Each time I look at that flag, I’m reminded that our destiny is stitched together like those 50 stars and those 13 stripes.  No one built this country on their own.  This nation is great because we built it together.  This nation is great because we worked as a team.  This nation is great because we get each other’s backs.  And if we hold fast to that truth, in this moment of trial, there is no challenge too great; no mission too hard.  As long as we are joined in common purpose, as long as we maintain our common resolve, our journey moves forward, and our future is hopeful, and the state of our Union will always be strong.”

Obama and the Biracial Factor: The Battle for a New American Majority, published 1 February, can now be purchased at 20% discount from the Policy Press website.  

Analysing policy change: institutions and ideas

The analysis of continuity and change is a preoccupation for scholars of the policy process. While a range of frameworks have been proposed, it would be fair to say that institutionalist approaches are currently flavour of the month. A long-standing challenge for historical institutionalism, however, is an asymmetry in its explanatory power. While plausible accounts of stability and continuity have been offered – invoking notions such as path dependency and lock in – providing credible accounts of policy change has proved more challenging.

Recent debate has called for a move “beyond continuity”. The idea of agents exploiting ambiguity within institutions has been proposed as one way forward. Another focus of attention is the role of ideas and how they might be deployed strategically by political actors to achieve change. We are even encouraged to look to a new – discursive – institutionalist approach.

Looking back over the articles published in Policy & Politics this year I reacquainted myself with the brief paper by Béland and Waddan* on policy successes and failures experienced by the Clinton and Bush administrations. The paper is based around a pair of successful policy changes and a pair of failures, one each for Clinton and Bush. The starting point for the paper is that the selected case study reforms are interesting because the successes and failures do not line up well with political preconceptions. While Clinton succeeded with welfare reform in 1996 he had earlier failed with reform to health insurance. Yet, the flavour of the welfare reform was considerably to the political right of more conventional Democrat territory, while the health insurance reforms should have played to the Democrats’ strengths. Similarly, Bush’s attempt to reform social security addressed a traditional Republican bugbear, but was ultimately unsuccessful, while he legislated for Medicare reforms that represented a commitment to increase government spending on welfare significantly.

In their discussion of these cases Béland and Waddan bring out the role of institutional barriers to change in explaining policy failure. They highlight concentration of power and embedded sectional and industry interests as standing in the way of change. While the forces of conservatism in the cases of successful policy change were weaker that was not felt to be an adequate explanation of the difference. In order to understand these policy outcomes there needs to be an awareness of context and a recognition that ‘depending on the context, factors like strategic choices, political judgement, and even chance can facilitate or complicate change’ (p227). These factors in their turn can be influenced by, for example, the perceived state of public opinion or the electoral cycle. An intersection of factors can result in apparently counterintuitive outcomes. The authors argue that ‘recognising this basic contingency inherent to the policy process helps leave room for agency within the institutional framework’.

In passing Béland and Waddan also provide food for thought on more detailed issues such what form policy proposals should take to maximise the chances of success. Is it most appropriate to bring forward detailed policy proposals so as to offer transparency, but greater ammunition for critics seeking to undermine the case for change? Or should governments bring forward broad policy positions and aspirations, with detail to be filled in later? The risk here is that it can lead to accusations that the proposals are premature. Key stakeholders may be unwilling to support something that is considered too vague. Presidents Clinton and Bush tried different strategies at different times – and Béland and Waddan’s account provides evidence of policy learning in this respect – but there was mixed results. Again, context is important.

Having reread their paper I feel that Béland and Waddan offer policy scholars much to reflect on. The answers they provide will not satisfy everyone, and in some areas the argument feels like it needs developing in more detail. But it represents a valuable step forward on our collective journey to a fuller understanding of the vagaries of policy.

Béland, D. and Waddan, A. (2010) The politics of social policy change: lessons of the Clinton and Bush presidencies, Policy & Politics, vol 38, no 2, 217-233*

Alex Marsh, Management Board, Policy & Politics

* This article is only available to subscribers. If you are not subscribed and would like to read this article, why not sign up for a free trial at http://www.ingentaconnect.com/content/tpp/pap/trial