GEEKOUT: Travel Behavior with Pat Mokhtarian

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Additional content from Pat Mokhtarian and on Travel Behavior and the incredible work being done at Georgia Tech.



[analog radio tuner scanning stations]
[big band swing rendition of Ramblin' Wreck from Georgia Tech]
[interposed voices of Steve McLaughlin] ...sounds incredibly sounds have abilities that span...I'm really geeking out here.
[applause and laugh track]
[big band swing rendition of Ramblin' Wreck from Georgia Tech]

[race car sound]

Pat Mokhtarian: The interstate driving is the part that's tedious, that's boring, and that's often easy. Now, even easy has challenges with weather, with road construction, with the unexpected. So nobody's saying, “I think day after tomorrow might be a little premature,” but that might well be the first application to be in widespread use. And even then, one would have to imagine that you're going to have the interstate segment that may be automated, but when you're driving in town, you need an alert driver with hands on the wheel at least, again, for another decade or two after that. So it will be phased, and that's part of the interesting challenge as well—how do we get from here to there so we can imagine or start to imagine a fully automated vehicle future? But there are a lot of pathways between here and there, and that's really kind of a challenge right now.

I was learning about travel behavior models in graduate school. And at that time it was most common that the explanatory variables, if you will, in those models—the typical factors that explain people's behavior about travel, in particular, are travel time and travel cost—we want the shortest trip possible and the cheapest trip possible. And we'll throw in some demographic variables because maybe income affects things, all else equal or gender or household size, that kind of thing—vehicle ownership.

But again I was realizing that, well, attitudes ought to be in there somehow. And I learned through taking courses in marketing research and psychometrics that there are well-established ways of measuring attitudes. Now, there are lots of pitfalls in doing so because, as you can imagine. For one thing, people don't even articulate to themselves, sometimes, what their attitudes are. So when you give them an attitudinal statement and ask them to strongly disagree, to strongly agree with it, they may be, for the first time, trying to figure out what their position is. So there's a certain amount of volatility in the attitudes that people report having. And also, there are all kinds of subtle biases: There's the social desirability bias, so they may want to look pro-environmental whether they really act that way or not. And in some cases, again, they don't even realize themselves that they're kind of projecting a persona that otherwise may not fit them. But there are techniques in survey design—and I teach a graduate class in survey design methods—so there are lots of little tricks to help reduce those biases; we don't necessarily get rid of them entirely. But a well-designed survey, I think, can go a long way toward eliciting at least a kernel of truth, if you will, about people's attitudes.

So when I design a new survey, I just give a lot of thought to what I think the important variables are given whatever behavior I'm interested in analyzing whether it's telecommuting adoption or the adoption of a ride-hailing alternative, and the future automated vehicles of course. So what are the, you know, the characteristics of the alternatives that are important? So those might be the more objective variables, if you will. But also, what are the attitudes that are important? And then we spend tons of time writing attitudinal statements, refining them, pretesting them, getting enough of them to kind of triangulate, if you will, on an attitude of interest, doing that for multiple attitudes of interest. And so it's a long process that I think is often underestimated. I try to teach my students in the class that you can't possibly do justice to a really good attitudinal survey in a short amount of time. And so, but having said all that, it's served us very well over the years. I think we can do a respectable job of measuring attitudes of incorporating those measured attitudes as explanatory variables into models.

[car engine revs, car horn]

Another thing that I realized early on in graduate school was that we'll never be able to predict behavior with certainty. So again, that's one of the fascinating things about people is that they're so unpredictable. And what I loved was that I was learning about probabilistic models. So the whole point of these models is not to predict what people will do, but rather it's to predict what's the probability that they will do this as opposed to that as opposed to that. So it just resonated with me that these probabilistic models really fit our inability as analysts to ever know with certainty what humans are going to do. But we can increase the skill that we have in predicting what they will do i.e. raise the probability that will predict the action that they ultimately take.

[transportation terminal sounds]

That has been very heartening to see the increased level of support for transit and in some counties that historically, at least on net, had not been supportive of it. And that may be partly a millennial influence as well. Certainly I think a generational shift in how transit in general is perceived and in Atlanta in particular. So I think there's a much wider spread understanding now that we need it throughout the entire metropolitan area and not just in Fulton County or the surrounding inner suburbs if you will. So that is exciting.

I hesitate to give much advice to people who are out in the trenches, and I think they're already aware of the kinds of things that need to be done. I'm delighted to see more attention being paid to bicycle infrastructure, to making locations more pedestrian-friendly and more mixed use so that we have more activities to walk to or bike to. So I think that's also a thrilling development here in Atlanta and around the country that in the past car was king, and they got first priority and everything else had to wait in line. Now I think much more attention is being paid to the entire portfolio of transportation options and the need for having bike when bike is appropriate, and being able to walk when walking is appropriate.

I think most people are not going to walk everywhere they go or bicycle everywhere they go, but just having the option would be so refreshing. And in many cases, there aren't sidewalks or there, you know, the sidewalks are broken and impassable or discontinuous—so you get on one for a little while and then suddenly you have to cross a busy street to get to someplace where you can keep walking. So we have a long way to go but it's really reassuring that some funds are going to be devoted to the problems we have.

Another area, of course, is making transit more attractive again to the choice rider. I think more could be done with station area development and attracting people to transit stations almost as destinations in their own right, but certainly as interesting and effective places to hang out for a little while and, of course, outfitting transit vehicles to make it easier to work on them or to use the time in other meaningful ways would also be helpful.

[traffic noises, traffic reporter]

[Ramblin' Wreck from Georgia Tech marching band rendition]