From black and white to shades of grey – the flawed world of expert knowledge dissemination in transport

THIS ARTICLE has been initially published in Local Transport Today, a specialist information magazine now established for over 30 years, underpinned by a subscription fee sufficient to cover its cost, though I don’t think anybody is making a fortune from it. In association with that, and as part of the fast-evolving world of digital knowledge, my article has then also be published on TAPAS, a recently established mission-led on-line collection of work like this, that makes its content available at a number of access levels including an entry-level free-to-view, and with the facility to host discussion arising from what the authors of its articles have said.

I am pleased to recognise the contribution of both LTT, and now TAPAS, to the professional consideration of important transport matters, and the demonstration of a significant degree of public interest by their founders and custodians. Both have an engaged editorial team who help commission and effectively present the material, though the task of ensuring quality in such publishing environments is a collaborative effort between authors and editors and – on occasion, when necessary – readers. What is in it for the authors is not money, but access to, and sometimes engagement with, an appropriate and knowledgeable audience. It’s a publishing model I feel very comfortable with- and have been a contributor to LTT for over 20 years now.

It is good to have seen it evolve and survive in the face of disruption from the digital technology revolution, challenges to its commercial model, and the arrival of many new upstarts not always bringing the same values and commitments to quality and integrity. For a while Twitter seemed to potentially be the perfect adjunct to such a model, as it facilitated the creation of a network of interest widening access to the full texts of articles published in a wide variety of different formats. That role still exists, but has noticeably been reduced by recent developments making self-contained minority networks of goodwill and common interest liable to be overwhelmed by different minorities of violent or unsavoury focus.

But the bigger context is a concern of the wider publishing scene on serious transport policy, theory, methodology and practice, which has now become a complex mish-mash of hugely expensive journals and books; cheap and free journals and books; and very expensive, or completely free, reports provided for commercial or policy interest. All this activity has been, and is still, partly protected by the interaction of outdated concepts of copyright and under-pressure concepts of public service, but vulnerable to the ‘Wild West’ features of the internet and social media, and now perhaps the coming of AI-generated content. And bubbling under all this are the twin panics we all face in the modern world – in that that we can’t actually handle or process all the information that’s now available.

Some significant contributions to transport thinking - but not from the universities

Police chief Alker Tripp’s latest original thinking on urban traffic from 1943

Glanville and Smeed of the Road Research Laboratory on road traffic requirements from 1957

The ICE’s examination of the problem of and responses to traffic congestion from 1989

The SACTRA report on induced traffic generation from 1994

Currently, both the youngest and the most senior authors are under great pressure by their own employers or academic institutions to write and publish more papers than – sometimes – it is at all evident that anybody wants. There is meanwhile no confidence that the various different mechanisms of quality control actually ensure quality. And as far as traditional ‘academic publishing’ is concerned, the supply of unpaid, willing, competent and disinterested referees is under great pressure, often with resulting long delays, or discontent with quality, or both.

At the heart of all this, I believe, is a simple economic relationship – expressed as the slogan ‘information wants to be free’ – resulting from a breakdown of the link between the cost of making information available, and its price. This is partly due to the internet, of course : there is virtually zero marginal cost of providing access to an already-published journal article, but the price may be £20 or £50 for an electronic copy of a 20 year old paper, protected only by the copyright, which had been transferred from the author to the publisher, and which has paid its original costs years ago, in a one-sided contract almost entirely in the publisher’s commercial interest. There is a version of ‘free-to-view’ publishing supported by commercial publishers, but it depends on heavy charges to authors of their institutions.

The pricing for small circulation academic books, based historically on the high set up costs for a low print run, has meanwhile lost all contact with the actual costs which apply. Authors are required to provide camera-ready electronic copy prepared by themselves, and a ‘print-run’ can easily be little more than printing on demand to meet actual orders. Research is mostly funded by public grants or individual interest, but is then assigned to a publisher who sells it back to the research organisation’s own libraries, also funded by public grants. ‘Being published’ remains the core attribute that it is monetised, but the principles behind that are rarely reviewed. A new feature is free access to a ‘preprint’ version on Universities’ own sites, but access if you are outside the University networks (which most individuals professionally working in transport are) is not guaranteed, and ensuring citations are accurate is difficult. New networks are being set up specifically to give unimpeded, free, convenient or cheap access to academics’ work to the academics who have done it, and some of these networks are illegal and unpoliceable. Big commercial publishers are very rich, but only because they are able to get their product, and a large part of its production costs, paid for by somebody else, or done free by the producers. And, as mentioned, there is the coming of AI with undisclosed algorithms, unpoliceable interpretations, and no protective conventions of credit and citation of sources.

This has all the signs of an economic bubble. There is far more product than anybody can keep track of availability is restricted by copyright and commercial considerations, extremely high average prices, extremely low marginal costs, and widespread dissatisfaction damped mainly by fear of the personal or institutional consequences of rocking the boat.

How did we get here?

No doubt there is some distortion in my memories of the early days of my career in transport as a young researcher. But I don’t think I’m imagining that the stresses and pressures I was aware of then were very much less painful than young academics at the beginning of their career now. I started work for an MPhil, which became a PhD, in the newly created Research Group in Traffic Studies, as it was called, at UCL, in 1966-1974. It had been set up by Smeed, Wardrop and their scientific civil service colleagues leaving the Government Road Research Laboratory.

I had a student grant for 2 years and then a junior research post at the same time. My PhD took 7 years altogether, including an 18 month delay for a resubmission. During this time I published a few papers, conference presentations, and reports, which I enjoyed, but I don’t remember any pressure to do so or any great difficulty in getting them accepted. I then joined the Greater London Council for 5 years (from where I also published a few papers, including the one I consider my most ‘purely’ academic), and then moved to another newly created research group in Oxford, initially as deputy director, where I stayed for 17 years, publishing a lot more papers and reports on interesting projects. The life style in both groups was quite hard work, daily physical presence, with a group of senior and junior researchers all based in the same building, all with their own personal desk and office space. We shared communal tea or coffee breaks, perhaps as a relic of the civil service and industry background of many of the staff in the first generation of transport groups. There were all sorts of personal and financial pressures, but there wasn’t a moment where I imagined I wanted a different sort of life, or felt the pangs of despair. Life, to be honest, felt pretty satisfying.

One key difference from today – which I didn’t really realise at the time – was how new academic transport studies was as a discipline. This was an exploding field of information generation, interpretation and discussion. The journals which arrived in our library were mostly of the same academic age as I was. The Institute of Transport bulletin, perhaps the oldest, was a serious publication that had dated back to the 1930s, and published serious thoughtful research such as Smeed and Wardrop’s ‘An exploratory comparison of the comparative advantages of cars and buses in urban areas’. (The journal later became the CILT members magazine of short articles, in colour). Traffic Engineering and Control had also been around for some 10 years, and was the monthly journal which headed the list of citations by both academics and practitioners. But Transport Economics and Policy was only founded in 1967, as were Transportation Research and Transportation Science. Accident Analysis and Prevention in 1969. The new Transportation, and Transport Planning and Technology, were both launched in 1972.

So half a dozen journals came into the library, mostly quarterly, and typically containing 6-10 articles in each. Just think what that meant. Every week or two, you could browse every paper in the latest issue of one of the journals, and find that there were one or two really worth reading. So we did. Quite often we’d talk about one of them, because we were all seeing the same articles in the same journals. That was ‘the literature’. We could keep up with all of it. Imagine!

In 1970-1 there was an important Government report published, written by Dame Evelyn Sharp, a formidable figure famous as the first ever woman Civil Servant to be Permanent Secretary of a Government Department, about future needs of education and training for transport planning – she called it, astonishingly, “Transport Planning: The men for the job” (I’ve never known whether she was making a point. At the time I don’t remember anybody making a comment about the presumption that the job was for men). It recommended a big increase in transport education including at Masters level, and the result was a big increase in the sector, and consequent growth in the number and size of academic transport research centres, jobs, research degrees, and journals.

An error of judgement: ‘Impact Factors’

This expansion was a world-wide trend, and one consequence has been that it is surely now quite impossible for any individual to imagine that you could ‘keep up with the literature’, especially because the Universities allowed themselves to be persuaded that their own success and funding was dependent on putting more and more pressure on their staff and students to publish, as a necessary condition for appointment, promotion, funding and other targets.

So there were more and more people writing more and more papers, and it was difficult or impossible to keep up with them all. But it was at the same time necessary to find a way of judging performance, and this was the context in which the idea of the ‘impact factor’ of research took hold, initially as a relatively simple idea that the impact of your research could be measured by counting the number of times other researchers referred to it. This was quite a coup for the transport journals, since it tied in the measure of success to the journals themselves, later expanding to a series of rather more complex indicators, but never really grappling with a more profound idea of research impact as actually changing the world, for good or bad. One distinction was whether you should count citations in all sources (which Google Scholar does), or only in the rather narrowly defined ‘proper’ academic literature, specifically the journals published by the increasingly large journal publishers, with their own protocols, favoured by such measures as Scopus, itself the property of the biggest journal publishers.

Influence and importance in transport thinking: which of these has mattered most?

Seminal studies like these...

...or academic journals like these

However defined, my own view is that the designation of a count of the number of times other people mentioned your research, as an ‘impact factor’ was cleverly, but misleadingly, titled, because it replaced the important, but difficult, issue of what effect your research had had. The easily measurable count of citations, led in turn to minor corrupt practices and pressures. This created a self-continuing explosion of papers out of proportion to the demand for them – journals essentially became machines for supply, a service for authors rather than readers, and generation of significant profit, but reducing job satisfaction. It also had the unintended effect of drawing attention to how pitifully small the number of citations most journal articles had, often low single figures, which was demoralising. Academic appointment committees often became more concerned with variants of this index, which replaced discussions about the actual content of one or two of the best pieces of work each candidate had done, which seems much more important to me. There were also distortions as between disciplines, where the publication cultures are quite different (e.g. fields in which multiple authored papers are the norm, and those where one or two authors are more common) and between individuals especially the practice of professors adding their names to the publications of their students.

A bigger conceptual error: ‘Grey Literature’

This ‘establishment’ environment was keen to protect itself – and invented ways of doing so. ‘Grey’ literature emerged as a commercially-designed labelling system based on the assumption that the intellectual merit of published work is associated with a sort of hierarchy in which refereed papers in academic journals are the peak. These might be joined by some, but not all books, also published commercially and using rather similar practices and style. Meanwhile the so-called ‘grey literature’ was treated as a second class system of published work, very diverse in nature, in which is included self-publication by authors, commissioned research published by public or private clients, the work of think-tanks and lobby groups, organisations without academic credentials or practices, ad hoc commissions and committees no matter how prestigious or intellectually powerful, and the publications of government itself – not to mention the ‘non academic’, but professionally important, magazines like LTT, read by an audience of practitioners working in the real world. The scientific and intellectual work of Government scientists, published free by Government, also counted as grey literature, and thus has not appeared in the citation lists purporting to be the custodians of genuine intellectual work.

This defining policy of ‘grey literature’ was in some ways a kind of apartheid, and certainly an approach of quite astounding intellectual arrogance, which by and large neither academic researchers nor governments have challenged. But the key reason why it is harmful is because – especially in the field of transport methodology, policy, planning and practice – it betrays a profound ignorance of where the dominant ideas in practice in transport research have actually come from. It does not reflect the actual history of the disciplines themselves.

The dominant intellectual approaches in transport policy have, in fact, been mainly a creation of civil society, and the institutions of government and the public sector, not the academy. The first conceptualisation of the economic idea of consumer surplus was from Dupuit, a French engineer, in the context of a discussion of road tolls in the 1840s. The basic approach to the theory of traffic flow, including the central speed flow relationship and all that stems from it, was the creation of the scientific civil service, especially in the Government’s Road Research Laboratory after the 2nd World War, and similar organisations overseas. So also was the approach of ‘predict and provide’, developed by the London County Council in 1944-5 in preparation for post war reconstruction, and at the national level in planning the Motorway network in the 1950s. Even earlier, the foundations of traffic calming in the context of a hierarchy of local and long distance travel was elaborated by the Metropolitan police, led by Alker Trip as deputy commissioner, and taken up by Colin Buchanan, a civil servant.

Part of the reason for this was that the ideas of town and country planning were most heavily influenced by architecture, and road planning by Civil Engineering. While both disciplines were of course present in Universities, their main activities, specialisms, funding and employment were outside.

The same tradition has continued throughout the modern period. Think of the major published work where ideas of transport policy and practice were defined and debated. Think of the great intellectual discussions in the 1960s – Buchanan Report, the Beeching Report, the Smeed report on road pricing. Then Margaret Thatcher’s Road Programme ‘Roads for Prosperity’ in 1989, the ACTRA and SACTRA reports on modelling, forecasting, environmental appraisal, induced traffic, and transport and the Economy in the 1990s. ‘This Common Inheritance’ in 1990, and the pathbreaking 18th Report of the Royal Commission on Environmental Pollution on Transport in 1994, through to the current work of the Committee on Climate Change, which is surely at least as important as any of the environment departments in Universities. The Eddington Report on roads and the economy in 2006. And TAG itself, the transport appraisal guidance, growing from the in-house Ministry of Transport Mathematical Advisory Unit in the 1960s, through to the continually evolving structure that in principle dominates road appraisal today. The House of Commons Transport Select Committee reports, at their best, contain evidence reviews of the highest intellectual standard.

By and large, all this literature has been published, remains available usually free, and represents the core library of intellectual application to problems of transport policy, congestion, environment. To think that any serious contribution to advancing this theory and practice can be done by treating this intellectual tradition as inferior or subordinate to the academic journals is absurd.

A small further credit to the likes of LTT here. Keeping track of the emergence of all this information in real time has required a specialist press with a ‘nose’ for what is being produced of significance and value. LTT has been amongst those doing that job for a third of a century now, and I am not aware of any academic equivalent with either the suitable radar, or speed of observation and alerts, to do this invaluable job.

So the core of my proposition is that the there is a central intellectual structure of transport planning, method and application, and this is the product of power and civil society, not academia. Academics as consultants have contributed to this structure on occasion, but have not owned or controlled it. But in saying that this structure is genuinely intellectual and influential, I’m not saying that it is always true, useful or perfect. Some aspects have enshrined what I consider to be serious strategic, logical and detailed mistakes, or wrong-headed assumptions. It’s nonsense to treat this literature as of second class or subordinate to ‘academic truth’. But the worrying thing is that the debates and contests have not primarily been pursued in the academic literature, whose contributions to the intellectual contests on transport policy have often been late, fearful, narrowly constrained, or focussed elsewhere.

So where is the intellectual debate, the challenge, the cut and thrust of argument today? In recent years two of the most important locations have been the formal procedures of planning inquiries, and formal challenges in courts of law. But the problem of these has been that the rules of debate – and the provisions of government Acts and Instruments – heavily police the question of what issues you are able to address and you are allowed to say. Take the key concept of de minimis, as applied to our field in the doctrine that the contribution of road building, or transport more generally, to carbon emissions is so small that it may legitimately be ignored in decisions about whether contested schemes or policies should go ahead. The debate is not primarily about the statistics or the analyses, but about whether criticisms may be voiced in forums where decisions are taken. It is a decision of great importance, to decarbonisation in general and transport policy in particular, but the current situation is surely unsatisfactory, where such an inherently important issue is not being resolved in either courts or by discussion in the relevant journals. I do not see any sign that it is the body of academic journals that have crystallised an effective intellectual challenge to the weak parts of the approach.

I conclude that any attempt to write an academically profound history of transport theory by assuming that that history has been made in the academic journals, rather than in the ‘grey’ literature, would not just be ignorant, it would also profoundly misunderstand and misrepresent the history of the subject itself.

In practice, the idea that Government publications are ‘grey literature’ is harmful to the quality of the work itself, since it can give Government the idea that it is immune from the rigours of properly independent peer review or conceptual challenge.

Is it Solvable?

In the current – and still changing – world of information I regret that don’t see that there is a solution to anyone managing the resulting volume of relevant material based on the old interpretation of ‘keeping up with the literature’.

My own view would be that the ‘academic’ publication standards and targets would better be set for a lower publication rate by individuals, allowing about half the number of publications, and much more emphasis on their quality. We shall also need an entirely new type of emphasis on a new sort of literature review and synthesis. But we are losing the battle to even stake out the ground, let alone define the content, and I don’t know if either is winnable now. Artificial intelligence may have something to offer, though it will need safeguards including its own algorithms for challenge and contest. But the one common part of all this is that sources of knowledge are multi-disciplinary, include civil society at least as much as academia, and must especially defend – or privilege if necessary – how challenge to orthodoxy is handled.

In summary, the dominant theories and practice of transport planning and policy represent a genuinely intellectual body of thought, which has largely been created by power and civil society not by academic commentary. In this it shares some features of the great church faith structures, including their tendency to presume truth. The academic contribution has been weakened by conventions like impact factors and grey literature. The question is whether there is now – as I believe – a very widespread academic concern about flaws of logic, evidence and effectiveness in the intellectual structures we have inherited, and if so, what can we do about it?