updated August 25, 2009:
For those of you who doubt I am doing work over in London, I have completed two other papers (in addition to “Too Expensive to Meter” based on my research over here):
- Levinson, David (2008) The Orderliness Hypothesis: Does Population Density Explain the Sequence of Rail Station Opening in London? Journal of Transport History 29(1) March 2008 pp.98-114.[download]
- Levinson, David (2008) Density and Dispersion: The Co-Development of Land use and Rail in London. Journal of Economic Geography 8(1) 55-57.
Network growth is a complex phenomenon. Some have suggested that it occurs in an orderly or rational way, based on the size of the places that are connected. David Levinson examines the order in which stations were added to the London surface rail and Underground rail networks in the nineteenth and twentieth centuries, testing the extent to which order correlates with population density. While population density is an important factor in explaining order, he shows that other factors were at work. The network itself helps to reshape land uses, and a network that may have been well ordered at one time may drift away from order as activities relocate.
This article examines the changes that occurred in the rail network and density of population in London during the 19th and 20th centuries. It aims to disentangle the ‘chicken and egg’ problem of which came first, network or land development, through a set of statistical analyses clearly distinguishing events by order. Using panel data representing the 33 boroughs of London over each decade from 1871 to 2001, the research finds that there is a positive feedback effect between population density and network density. Additional rail stations (either Underground or surface) are positive factors leading to subsequent increases in population in the suburbs of London, while additional population density is a factor in subsequently deploying more rail. These effects differ in central London, where the additional accessibility produced by rail led to commercial development and concomitant depopulation. There are also differences in the effects associated with surface rail stations and Underground stations, as the Underground was able to get into central London in a way that surface rail could not. However, the two networks were weak (and statistically insignificant) substitutes for each other in the suburbs, while the density of surface rail stations was a complement to the Underground in the center, though not vice versa.
Perhaps more interesting for the non-academic, we (Ahmed El-Geneidy, Feng Xie, and myself of the Nexus group) have put together three quicktime movies
- 1.The co-evolution of London population density and surface (National) rail
- 2.The co-evolution of London population density and the Underground
- 3.The co-evolution of London population density and surface (National) rail and the Underground
These can be accessed from here.
I was going to write about this, but someone beat me to it: London Underground Tube Diary – Going Underground’s Blog. There is a new ad campaign from Flora “Could you walk it quicker?” which suggests people should walk between locations that are close together for their heart. Of course, it would also relieve transit congestion, if taken up, as many stations are really quite close, especially after you consider the underground access costs, the closeness is shown on the maps at Shortwalk.blog. It points out the great distortions caused by the standard tube map based on the design by Harry Beck, which makes some close things seem far and some far things seem close.
One might call it Rod Pricing instead of Road Pricing, given the important role that Rod Eddington of Eddington Report fame is having on the Road Pricing debate over here. Two articles from the anti-pricing Telegraph
* here and
discuss the issue. Rod seems to have introduced some sense into the argument, suggesting it is only appropriate for city centers. In economic jargon, this is the area where marginal costs are increasing. On uncongested roads, marginal costs per use are falling or zero, the fixed cost of the road is spread across more users, but congestion has yet to set in. (This of course is concerned with congestion costs and construction costs, not environment costs, which should be dealt with differently).
The government moving towards zones (or cordons) is some progress on the issue. One must ask though whether the collection costs will be larger than the revenue in rural areas (I strongly suspect they will), or whether a few pence per mile will affect behavior much (I suspect it won’t).
Andrew Odlyzko and I recently (two days ago) finished a draft paper on the subject “Too expensive to meter: The influence of transaction costs in transportation and communication”, which he has put on his website
Representative James Oberstar from Minnesota, now Chair of the House Transportation Committee spoke to a State Legislative committee yesterday: No gas tax hike, less federal aid, Oberstar warns
Minnesota has not raised the gas tax in almost 20 years, while the cost of roads has of course gone up. While the legislature has passed (and may again pass) a hike in the gas tax, the Governor and putative Vice Presidential candidate Tim Pawlenty has vetoed, and promises to again.
In reality, motorists would probably not notice a 5 or 10 cent rise in the gas tax, that is within the natural volatility of gas prices on daily basis anyway. Second, the funds go to transportation, which is generally a popular use of the money. Third, the US financing context is rigged so states need to produce matching funds to obtain federal resources. It would seem locally advantageous for those in charge to pass (and sign) such a tax.
There is of course the question of how the money would be spent, and whether the spending priorities that would be enacted align with needs. This is particularly the case because we undercharge for the use of roads (like most of the world, there is no pricing of congestion impacts in Minnesota), and so overconsume, and thus have more congestion than we otherwise should. But gas taxes have the merit of having a low collection cost compared to tolling, so less is wasted.
Alas, the world is imperfect, and the question of which way is the best to proceed depends upon assumptions, and trading off the ideal with the achievable, which is the job of politicians.
The UK PM emails road pricing signatories, those who signed the petition opposing pricing. His letter is interesting from a number of perspectives, and was clearly written in part by transportation professionals.
However there is an (intentional?) misrepresentation of the induced demand problem hidden in the text.
If it is the “beginning ,not the end of the debate”, it has not got off to a good start. There are several elements missing from the context, though perhaps they will be brought back in:
1) Hypothecation (the British term for earmarking) – money raised from transportation should be spent on transportation (or its impacts). When talking about building facilities the PM says “Tackling congestion in this way would also be extremely costly, requiring substantial sums to be diverted from other services such as education and health, or increases in taxes.” Implying more money for roads from the same gas tax is less money for something else. This is because in the UK the petrol (gas) tax is used as a cash cow to cross-subsidize other sectors of the economy that should be paid for out of general revenue or otherwise. If people instead saw transportation taxes/tolls/prices as paying for transportation services, there would be more readiness to do so.
2) Local decision making – most travel is local, decision making about tolls and pricing should be local (though obviously there are positive network externalities associated with choosing a common technological framework).
In a less than overly popular move, Ken Livingstone has implemented the western extension of the Congestion Charge, as noted in the GuardianProtest greets congestion charge’s westward push BBC devoted almost the entire half-hour of local news last night to the topic.
Several things to note, though the evidence is anecdotal. First, students are on break this week, so traffic levels are lighter. That said, the buses seemed to make much better time.
Second, it is being billed more for environmental than congestion-relief reasons now, so the nominal motive has changed (the underlying motive, punish the car and raise money remains). Paying lip service to carbon reduction is now politically correct, whether or not this is the best way to achieve that end.
Third, the national government’s long-term road pricing scheme is becoming very unpopular with everyone but the environmentalists, as the public rightly sees it as a way to collect more money, rather than manage traffic and improve transportation. Perhaps hypothecation should be restored in England. The road pricing debate is spilling over on the congestion charge. Privacy issues are also re-emerging as critical.
Some of the roads in the old zone were empty enough during the morning that it felt like a ghost town walking around, all the cars are parked, no vehicles are moving. It is not quite that level in the western extension, though better than it had been … but again, this week is break.
I do believe a major mistake was made in letting residents of the west get to use roads in the east as if they were local. This will raise traffic levels in the east. A zone system would be much fairer, with perhaps some discount for those in the west. I am sure there were political reasons for this.
If the zone gets extended further, some form of zoning will be necessary, or it will lose all effectiveness.
It will be intersting to see the final analysis on traffic levels. I suspect the government lowballed the official congestion reduction estimates of 4 percent to be able to claim victory when a greater reduction occurs.