Master of Science, The Ohio State University, 2020, Civil Engineering

The purpose of this study is to assess the factors that may influence demand for a flexible commuter shuttle serving employees of a large medical center. In order to address this research question, a web-based survey was designed to collect and analyze the employees' current commute patterns, their attitudes toward and satisfaction with commute travel and various forms of transportation, and to investigate under what circumstances they might choose to commute using a demand-responsive commuter shuttle service. For this purpose, they were presented with a variety of hypothetical scenarios and they were asked to indicate how they would choose to commute under each of them. After the data collection part, a mixed logit model with error components was used to capture the probability of people choosing such a service and key insights and design ideas and implications for the commuter shuttle were developed.

Committee: Andre Carrel (Advisor); Mark McCord (Committee Member); Rabi Mishalani (Committee Member) Subjects: Civil Engineering

Master of Science in Engineering, University of Akron, 2013, Civil Engineering

This study focuses on the analysis of alcohol-impaired crashes in the State of Ohio. The alarming rate of alcohol related crashes across the country and across the state are cause for major concern to all peoples on the roadway, and to all citizens. In this study crash data from 2008-2012 is analyzed in order to determine the contributing factors of two types of alcohol related crashes. Mixed logit models are developed in order to determine the impact of crash characteristics including any unobserved correlated characteristics. Four models are developed for two comparisons using crash record information from the OH-1 uniform crash reporting form. One comparison outlines the difference between the injury severities of passenger car operators and motorcycle riders in single unit alcohol related crashes. The second model outlines the contributing factors for impaired and non-impaired operators in the same two-unit alcohol related crash. The models both identify the use of safety equipment as a major contributing factor limiting the severity of injuries to operators. The study also identifies rate of safety equipment use amongst impaired and non-impaired operators, finding a much higher rate of use with non-impaired operators. All four models also show a strong correlation to the size of the vehicle being driven with injury severity. The data set also identifies the critical age ranges for impaired operators, finding in passenger cars the age range is much younger, 20-39, while motorcycle riders the age group is found to be older, 30-49. Other results focus on roadway geometry, collision type, and vehicle speed.

Committee: William Schneider IV Dr. (Advisor); Stephen Duirk Dr. (Committee Member); Anil Patnaik Dr. (Committee Member) Subjects: Civil Engineering

Doctor of Philosophy, The Ohio State University, 2004, Agricultural, Environmental and Development Economics

This dissertation aims to provide answers to some of issues in dichotomous choice contingent valuation: the temporal structure of willingness to pay, practical guideline for survey design and generalized estimation method. The first essay proposes the temporal willingness to pay (TWTP) as an alternative definition of the present value of willingness to pay. In the survey of contingent valuation, a respondent compares TWTP with the present value of randomly assigned cost. TWTP enables the test for consistency of respondent's valuation with respect to payment schemes. Using a sequential test, the insensitivity of TWTP is tested on the data of oyster reef restoration programs in the Chesapeake Bay. The test result shows that TWTP is insensitive to the offered payment schedule or on the length of the stream of benefits of the project, which implies consistent willingness to pay for the environmental project. However, discount rates estimated from the data vary significantly across project lengths and time span between offered payment schedules. The second essay suggests a practical alternative design named a uniform design, to existing optimal or robust bid designs in contingent valuation. The uniform design draws cost assigned to respondent from a predetermined uniform distribution. Analytics and simulations show that the uniform design has lower bound of efficiency at 84 percent of D-optimum. Simulations demonstrate that the uniform design outperforms optimal designs when initial information is poor and outperforms robust designs when true values of parameters are known. The third essay challenges the theoretical and technical background of the simple logit model. Standard logit model in contingent valuation assumes i.i.d error distribution between initial and proposed states. Relaxing the restrictive assumption in the simple logit model requires a generalized estimation technique that utilizes a Gumbel mixed model. Estimation results show that correlation between two (open full item for complete abstract)

Committee: Timothy Haab (Advisor) Subjects: Economics, Agricultural

Master of Science, University of Akron, 2009, Civil Engineering

Standard multinomial (MNL) and mixed multinomial logit (MMNL) models are used to estimate the degree of influence bicyclist, driver, motor vehicle, crash geometry, roadway geometry and environmental characteristics have on bicyclist injury-severity, classified as property damage only, possible, non-incapacitating or severe. This study is based on 10, 579 crash observations in the State of Ohio from 2002-2008. A log-likelihood ratio test is used to divide the bicycle/motor vehicle crashes into intersection and non-intersection location crashes. These models are used as base models for intersection and non-intersection MMNL models. Many variables are significant in both intersection and non-intersection location models. But six variables influenced bicyclist injury-severity at intersection locations but not non-intersection locations. Four variables influenced bicyclist injury-severity at non-intersection locations but not intersection locations. Some interesting finding are at intersection locations, the likelihood for a severe bicyclist injury increases by 31% if the bicyclist is not wearing a helmet, 99% if the motorist is under the influence of alcohol, 144% if the motor vehicle is a van, 59% if the motor vehicle front strikes the side of the bicycle, and 337% if the crash occurs on a horizontal curve with a grade. Non-intersection locations show the likelihood for a severe bicyclist injury increases by 608% if the bicyclist is under the influence of drugs, 194% if the motorist is under the influence of alcohol, 91% if the motor vehicle front strikes the side of the bicycle and 122% if motor vehicle is a heavy-duty truck.

Committee: William Schneider PhD (Advisor) Subjects: Transportation