Saturday, July 18, 2009

The Cycle, Revised

My recent exchange with Jarrett Walker (see Jarrett's original post, then my reply, and Jarrett's response) about the concept of mobility has encouraged me to update my chart of the transportation cycle.

The discussion with Jarrett has allowed me to split the notion of transportation quality or value into two parts, mobility and comfort. What I've realized is that while mobility for all is important to me, comfort for all is a much lower priority. I think government should make it affordable for everyone to travel reasonable distances to jobs, shopping and other activities, but I don't think that subsidized travel needs to be particularly comfortable. Of course it would be nice, but heading off global warming is a higher priority for me.

However, when transit offers equal or better mobility compared with private cars (as it does in many parts of New York), then comfort can be the deciding factor. So both factors influence mode choice.

I've also redone the chart in Gimp, instead of the original MS Paint, which gives me cleaner lines. Hope you all like it.


Jarrett at said...

Like many good charts, this one raises more questions.

I assume that by mobility you mean not just travel time (which is the basis for my use of the term) but also cost. We see dramatic shifts in mode choice as fuel prices fluctuate.

"Comfort" is not a bad approximation of what is, more exactly, "the inchoate mass of unquantifiable and subjective values that influence mode choice. And of course the interesting question is how to balance mobility and "comfort".

Jeff said...

Comfort isn't important?

People are lazy, people want to be comfortable. If transit is simply good mobility, I'm not sure it will be able to capture a large market.
(Although if by mobility, you mean it is cheaper then I could see how it might cause people to change the way they travel).

You mention heading off global warming as important, but I can't honestly see mobility as being enough of a deciding factor to get people to switch to transit en masse to the point it will effectively head off global warming if it isn't a nice way to travel.

Cap'n Transit said...

I'm sorry my post wasn't clearer, Jeff. I was trying to say that comfort for all isn't a high priority for me, as an end in itself. But as I said above, it may be the deciding factor in getting people out of their cars.