www.TransformingTransportation.org

Taking the Middle Path:

Accessibility Analysis & Transport

Modeling

Kevin Webb, Principal, ConveyalPresented at Transforming Transportation 2015

Taking the Middle Path:Accessibility Analysis

& Transport Modeling

Kevin Webb

Sixteen Reasons Other Than Prediction to Build Models

1. Explain (very distinct from predict)2. Guide data collection3. Illuminate core dynamics4. Suggest dynamical analogies5. Discover new questions6. Promote a scientific habit of mind7. Bound (bracket) outcomes to plausible ranges8. Illuminate core uncertainties.9. Offer crisis options in near-real time10. Demonstrate tradeoffs / suggest efficiencies11. Challenge the robustness of prevailing theory through perturbations12. Expose prevailing wisdom as incompatible with available data13. Train practitioners14. Discipline the policy dialogue15. Educate the general public16. Reveal the apparently simple (complex) to be complex (simple)

3. Illuminate core dynamics?

Worst Case Best Case

The Transit App

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