IN WHAT OR WHOM DO WE TRUST? | JOHN DALES
Professional judgement needs to stand tall in the gap between modelling and opinion.
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FRIDAY 19TH OCTOBER
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I’m writing this on the way back from a first-ever visit to a political party conference, in this case the Conservatives’. Given that I’d been invited to speak at a fringe event on the often vexed subject of free parking, I was indebted to the Chancellor for having earlier set the scene by railing against a ‘Something for Nothing’ culture.
On the train up to Birmingham, I’d encountered a report in the Times headlined “DfT ‘could be sued over growth forecasts’”. This story was inspired by a “warning” that my fellow LTT columnist Phil Goodwin would make at the European Transport Conference in Glasgow the same day: that pension funds and other private infrastructure investors could sue the Department for Transport if official forecasts for long-term traffic growth fail to materialise. The Times also referred to the Transport Planning Society’s recent call for an urgent review of the DfT’s forecasts because they are “now so far from reality”. Coming in the week after the word “debacle” was done to death to describe the fun and games associated with the West Coast Main Line franchise, and after the ‘Revisit HS2’ clamouring that grabbed the WCML’s coat-tails, one might be excused for thinking that it’s become open season for having a pop at any who works for, or is vaguely associated with, the DfT. However, it’s by no means just the Department that should take any hits arising because of transport forecasts that fail to hit the mark. It is, to be frank, all those who make such forecasts without accompanying them with very clear health warnings, and all those who accept such forecasts without demanding to know what health warnings there should be. Especially in the context of the giant, global economic hole that we’ve all been trying to scrabble up the sides of over these past few years, you’d have thought that we’d have realised that any forecasts for periods beyond the end of next week should be filed under ‘Handle with Extreme Care’. And yet, here we are, at individual and Governmental level, expressing shock and horror that our long-range transport forecasting doesn’t seem to be very reliable. Of course it isn’t! Indeed, one might ask, when ever has it been? The rarity of accurate long-range forecasting, in my experience, suggests strongly that those that hit their marks do so more by luck than judgement. And it is judgement, in my view, that’s at the heart of the matter. Some fear to use it; some don’t know how to; some don’t have any (at least, not of the right kind); and some reject ‘judgement’ on the grounds that it’s just ‘opinion’. This latter concern is at one end of a continuum that has, at its other end, an unquestioning faith in the outputs from forecasting/modelling. Too many people seem to act like it’s a direct fight between one end and the other. In practice, both qualitative and quantitative considerations need to be held in tension in making any decision. The most fervent adherents to forecasting and modelling consider the work to be scientific, yet it’s often simply numeric. Transport decision-makers at all levels have for far too long been in the thrall of what I call “numbers masquerading as facts”. They’ve come to think that a decision can’t be justified unless there’s some kind of ledger in which the numbers in one column are different from the numbers in another. These numbers may be pounds sterling, passenger car units, ratios of flow to capacity, mode share percentages, or many other types of figure. We may not know (or care) how reliable they are, but – hell – we’ve got some numbers and we’re not afraid to use them. I can, and should, be equally harsh about what happens at the other end of the scale. At a conference on parking last week, most of the participants in a session I spoke at recounted their painful and often repeated experience of various key stakeholders, including decision-makers, simply refusing to be troubled about known facts concerning the pros and cons of particular parking management actions. “Why bother with evidence when we know we’re right?” seemed to sum it up. One recent ‘transport’ intervention that seems to exemplify the challenge we face in these regards is the new London cable car. Costing around £60m, over half of which seems to have come from commercial sponsorship, it has been criticised by some for being a vanity project rather than a transport project, and praised by others for being ‘great for London plc’ in all sorts of ways. I was reminded of this as I walked across the Thames on one of the Hungerford foot bridges the other day. I’ve seen a report stating that this pair of bridges cost €72m (2002 price and exchange rate), yet there always was a footbridge there and it was rarely congested. So, considered as a transport scheme, the cost of the Hungerford Bridges was plainly preposterous. This being the case, I wonder why I’ve never encountered anyone who is scandalised at the price tag cost or who hasn’t actively welcomed the change. The answer, I’m fairly certain, is that the bridges were much more than a transport project, they were what I call a ‘city project’, with the Wikipedia description of the previous footbridge – “narrow, dilapidated and dangerous - the scene of a murder in 1999” – perhaps helping to explain the broader context. The thing is, almost every single ‘transport project’ you can think of, especially the more expensive ones, aren’t just transport projects. They’re far more complex than that, and they need to be assessed – indeed judged – accordingly. “I think it’ll be great for the town” and “Computer says” are equally partial and inadequate responses to this challenge. As practitioners, we need to have greater confidence in our professional judgement, ensuring it’s appropriately informed by the best evidence available. It’s our job to challenge unquestioning acceptance of both numbers and opinions. As some at the DfT have recently realised, anything less may be considered professional negligence. |
As recent events have shown, conventional transport appraisal is no guarantee of wise judgement...
…and yet we question the wisdom of judgements that transcend conventional transport appraisal.
As the Hungerford Bridges show, there’s usually much more to transport projects than transport.
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