Browsing by Author "Wasfi, Rania A"

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    Markov Chain Model of Land Use Change
    (2015) Iacono, Michael J; Levinson, David M; El-Geneidy, Ahmed; Wasfi, Rania A
    The set of models available to predict land use change in urban regions has become increasingly complex in recent years. Despite their complexity, the predictive power of these models remains relatively weak. This paper presents an example of an alternative modeling framework based on the concept of a Markov chain. The model assumes that land use at any given time, which is viewed as a discrete state, can be considered a function of only its previous state. The probability of transition between each pair of states is recorded as an element of a transition probability matrix. Assuming that this matrix is stationary over time, it can be used to predict future land use distributions from current data. To illustrate this process, a Markov chain model is estimated for the Minneapolis-St. Paul, MN, USA (Twin Cities) metropolitan region. Using a unique set of historical land use data covering several years between 1958 and 2005, the model is tested using historical data to predict recent conditions, and is then used to forecast the future distribution of land use decades into the future. We also use the cell-level data set to estimate the fraction of regional land use devoted to transportation facilities, including major highways, airports, and railways. The paper concludes with some comments on the strengths and weaknesses of Markov chains as a land use modeling framework, and suggests some possible extensions of the model.
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    Measuring the transportation needs of people with developmental disability
    (2006) Wasfi, Rania A; Levinson, David M; El-Geneidy, Ahmed
    Measuring the transportation needs of people with developmental disability Abstract: The US Department of Health and Human Services Administration on Development Disabilities estimates the number of people diagnosed with a developmental disability in the United States as 4.5 million persons, which would translate to about 17,000 residents of Hennepin County, Minnesota. This research paper examines the transportation needs of adults with developmental disabilities either residing or working in Hennepin County through a survey of their existing travel behavior and their unmet transportation needs. The survey had both demographic and attitude questions as well as a travel diary to record both actual and desired but untaken trips. In this paper we report and discuss the main findings of the survey. It was clear from observing the returned sample that almost the entire surveyed population does not live independently. More than half of the surveyed population worked every day, while recreation occurred at least once a week for about two-thirds of the population, and more than half undertook social trips weekly. About 30% reported being unable to make trips they want to make and 46% unable to make trips they need to make. Public transit poses difficulties for this population both physically and intellectually. There were also specific complaints about the lack of transit service in addition to concerns regarding paratransit services. Community service providers received praise.
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    The Transportation Needs of Seniors
    (2012) Wasfi, Rania A; Levinson, David M; El-Geneidy, Ahmed
    Over 208,000 residents of Hennepin County, Minnesota are over the age of 55, a number that is sure to rise. This paper examines the transportation needs of the elderly in Hennepin County through a mail out-mail back survey of their existing travel behavior and their unmet needs. The survey had both demographic and attitude questions as well as a travel diary for recording actual trips and desired but untaken trips. We found that 87% of the sampled population feel they are independent travelers. Around 51% of the surveyed population indicated that they are transit users, 25% of them revealed their concerns about difficulties they are facing when using public transit. About 16% of transit users were concerned about waiting time for transit, while only 8% were concerned about the travel time. Only 15% of the surveyed population use paratransit. A large number of comments were received, which add qualitative flavor to the analysis that was conducted. Seniors recognize even if they are currently independent, that will not always be the case, and acknowledge they should plan.