Input Taxes, Output Taxes and Electric Vehicles.

From ArsTechnica Ford’s plug-in hybrids will talk to electrical grid This is for charging the cars at the best time of day (night), but in theory could be extended to a means for charging cars for electricity different than regular electricity, in other words, a mechanism for replacing the gas tax with a different energy input tax.

Fuel (or electricity) taxes are input taxes. Theory suggests it would be better to tax outputs (actual miles traveled, by time of day and location). This would send a more direct signal to consumers about the costs they impose on the system and others. The difficulty is that this may be a much more difficult enterprise from a variety of points-of-view (collection costs, political acceptability, and even technology (GPS shadows etc.)). As a second-best, input taxes are not too bad, it is better than a tax totally unrelated to usage, and the 20-30% reduction in collection costs may well make up for any inefficiencies.

Evolution of the Second-Story City: The Minneapolis Skyway System.

The following was recently published:
Corbett, Michael, Feng Xie, and David Levinson (2009) Evolution of the Second-Story City: The Minneapolis Skyway System. Environment
and Planning b
36(4) 711-724 [doi]

This paper describes and explains the growth of the Minneapolis Skyway network. Accessibility is used as a major factor in understanding that growth (i.e. does the network connect to the location(s) with the highest accessibility, followed by the second highest, and so on). First, employment opportunities are used as the measure of activity and are based off of the square footage of buildings and/or ITE trip generation rates. Using information about the buildings located downtown for each year
since the first skyway was built, the accessibilities of each of the connected and adjacent unconnected blocks were calculated for every time period the skyway system expanded. The purpose is to determine how often the expansion connected the block with the highest accessibility. The results show that though important, accessibility was rarely maximized, except in the early stages of development. A connect-choice logit model relating the probability of joining the network (in a given year) to accessibility and network size was employed. The results show accessibility does remain an important factor in predicting which links are connected. Physical difficulties in making connections may have played a role, as well as the potential for adverse economic impacts.

Keywords: Network growth, Skyways, Minneapolis

NY Transportation Authority Cites Schedules as Copyrighted Material

From ReadWriteWeb NY Transportation Authority Cites Schedules as Copyrighted Material
The NY MTA is trying to take-down an iPhone application that delivers train schedules. Another example of appalling over-reach on copyright. Presumably they will lose if this goes to court, buy why do they even bother?
All transit schedules (and traffic counts, and traffic signal timings, and any other transportation data you can imagine) should be free, open, and in a standard, documented, machine-readable format.