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Title: Conservation and population biology: genetics, demography and habitat requirements of the Atlantic coast beach mice.
Creator: Kalkvik, Haakon, Parkinson, Christopher, Stout, I, Hoffman, Eric, Weishampel, John, Doonan, Terry, University of Central Florida
Abstract / Description: The conservation biology field seeks to preserve biodiversity and the processes shaping that variation. Conservation biology is intimately tied to evolutionary research, in order to identify evolutionary distinct lineages that may be in danger of disappearing. Interestingly, patterns and processes of lineage divergence and persistence change with respect to spatial and temporal scale. I seek to evaluate biodiversity, the factors that have shaped this heterogeneity, and how this variability...
Show moreThe conservation biology field seeks to preserve biodiversity and the processes shaping that variation. Conservation biology is intimately tied to evolutionary research, in order to identify evolutionary distinct lineages that may be in danger of disappearing. Interestingly, patterns and processes of lineage divergence and persistence change with respect to spatial and temporal scale. I seek to evaluate biodiversity, the factors that have shaped this heterogeneity, and how this variability persists. To accomplish this I used a phylogeographic approach as well as niche and population modeling on the Peromyscus maniculatus species group found widely distributed in North America. My emphasis was on the southeastern U.S. species P. polionotus and its distinct beach forms. At a continental scale, I found that environmental niches are likely involved in generating and/or maintaining genetic lineages within the P. maniculatus species group. These findings add to a growing number of studies that have identified lineages occupying different environmental spaces. At a regional scale, I supported the hypothesis that barrier islands on the Atlantic coast of Florida were colonized by an ancestral form of P. polionotus by a single colonization, from the central Florida area. Subsequently, at least two distinct lineages diverged (P. p. phasma and P. p. niveiventris). I also found evidence that suggests that the extinct form of beach mouse (P. p. decoloratus) is part of the P. p. phasma lineage. At the population level, I evaluated changes in genetic diversity in historical samples compared to those that experienced recent human encroachment on natural habitat I used tissue preserved in natural history collections to compare with live-trapped specimens, and found that P. p. niveiventris has maintained historical genetic diversity levels. I suggest that the continuation of historical levels of genetic diversity is due to the presence of a single large area of continuous habitat in the central portion of the species' current distribution. Finally, I evaluated the importance of scrub and beach habitat to the population dynamics of beach mice. Beach mice have traditionally have been associated with beach dunes rather than with the scrub habitat found more inland on barrier islands. Using almost three years of capture-recapture data from Cape Canaveral Air Force Station (CCAFS), I created a stochastic matrix model to assess the relative contribution of populations from the two different habitats to a variety of demographic measures. Both field data and model results provided evidence that the population dynamics of beach mice may rely much more on scrub habitat than formerly documented. Overall, my research emphasized a hierarchical approach to evaluate biodiversity and the processes shaping differentiation at different spatial and temporal scales. The methods and findings give insight into speciation at different scales, and can be applied to a wide range of taxa for questions related to evolutionary and conservation biology.
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Date Issued: 2012
Identifier: CFE0004392, ucf:49372
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0004392

Title: TAXONOMY VERSUS PHYLOGENY: PHYLOGEOGRAPHY OF MARSH RABBITS WITHOUT HOPPING TO CONCLUSIONS.
Creator: Tursi, Rosanna, Hoffman, Eric, University of Central Florida
Abstract / Description: Subspecific taxonomic designations solely based on morphological characters can often lead to erroneous assumptions about the evolutionary history of populations. This study sought to investigate evolutionary questions and conservation implications associated with morphological subspecific designations of island populations. To this end, I focused my attention on the Lower Keys of Florida, a unique chain of islands with well-known geologic history and rich in endemic, endangered subspecies. I...
Show moreSubspecific taxonomic designations solely based on morphological characters can often lead to erroneous assumptions about the evolutionary history of populations. This study sought to investigate evolutionary questions and conservation implications associated with morphological subspecific designations of island populations. To this end, I focused my attention on the Lower Keys of Florida, a unique chain of islands with well-known geologic history and rich in endemic, endangered subspecies. I employed genetic analyses to evaluate historical variation and contemporary restriction of gene flow between the endangered Lower Keys marsh rabbit (Sylvilagus palustris hefneri) and its sister mainland taxa. A Bayesian phylogeny using 1063 base pairs of the mitochondrial cytochrome b gene did not recover reciprocal monophyly of the three named subspecies, and a 95% statistical parsimony haplotype network showed haplotypes being shared among subspecies. Furthermore, clustering analyses using 10 microsatellite loci identified a break within the Lower Keys, separating the western Lower Keys from the island of Big Pine Key. Surprisingly, Big Pine Key grouped with mainland populations and exhibits higher genetic diversity than the western Lower Keys islands. These unexpected findings suggest either a stepping-stone colonization pattern or recent gene flow between the mainland and Big Pine Key via natural dispersal or undocumented man-mediated transfers. Although these results suggest that subspecies designations within S. palustris are unwarranted, this study supports the designation western Lower Keys population as a discrete unit of conservation with regard to both DPS and ESU criteria. The importance of using several lines of evidence to uncover the evolutionary history of populations and implications for the conservation of island populations are discussed.
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Date Issued: 2010
Identifier: CFE0003418, ucf:48380
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0003418

Title: Zooming In On The Money Shot: An Exploratory Quantitative Analysis of Pornographic Film Actors.
Creator: O'Neal, Erin, Huff-Corzine, Lin, Corzine, Harold, Pritchard, Adam, Potter, Roberto, University of Central Florida
Abstract / Description: Sex work is one of the rare elements of our society that is both accepted and stigmatized. Ironically enough, it is stigmatized without being studied in depth. The truth is we know very little about sex work and even less about pornography(-)the most legal of genres. While researchers have spent a great deal of time determining the effects that pornography has on viewers, particularly juvenile viewers, little research has been done on the men and women who make pornography. A 43 question...
Show moreSex work is one of the rare elements of our society that is both accepted and stigmatized. Ironically enough, it is stigmatized without being studied in depth. The truth is we know very little about sex work and even less about pornography(-)the most legal of genres. While researchers have spent a great deal of time determining the effects that pornography has on viewers, particularly juvenile viewers, little research has been done on the men and women who make pornography. A 43 question survey was created and disseminated to those in the pornographic film industry, both amateur and professional, resulting in 210 respondents from all walks of life. The results of the inquiry show that social scientists know relatively little about working in pornography, having a profound impact on the current discussion and future research. Additionally, this investigation presents a new and creative method for surveying hard to reach, hidden, or sensitive subject populations that will aid in aspects of future research on sex work and other stigmatized behaviors.
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Date Issued: 2016
Identifier: CFE0006365, ucf:51532
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0006365

Title: Population dynamics and environmental factors influencing herbs in intact and degraded Florida Rosemary scrub.
Creator: Stephens, Elizabeth, Quintana-Ascencio, Pedro, VonHolle, Mary, Fauth, John, Levey, Douglas, University of Central Florida
Abstract / Description: Species have complex and contextual relationships with their environment; both the relative contributions of life-history stages to population growth and the effect of environmental factors on each stage can be different among co-existing species. Timing and extent of reproduction, survival, and mortality determine population growth, species distributions, and assemblage patterns. I evaluate the role of habitat (intact, degraded) and microsite (shrub, leaf litter, bare sand) on population...
Show moreSpecies have complex and contextual relationships with their environment; both the relative contributions of life-history stages to population growth and the effect of environmental factors on each stage can be different among co-existing species. Timing and extent of reproduction, survival, and mortality determine population growth, species distributions, and assemblage patterns. I evaluate the role of habitat (intact, degraded) and microsite (shrub, leaf litter, bare sand) on population dynamics of Florida scrub herbs. Isolated overgrown shrubs and extensive bare sand areas in degraded scrub were expected to decrease seed predation, reduce competition of herbs with shrubs, and provide larger habitat for recruitment. I provide evidence that habitat and microsite variation influenced demography of five endemic and two common native species through effects on seed removal, emergence, and establishment. Habitat and species affected seed removal: endemic species with large seeds were removed in higher frequency in degraded habitat, likely by vertebrates, while species with small seeds were removed in higher frequency in intact habitat, by invertebrates. There was no evidence of differences in individual seed production between habitats for the two common species, C. fasciculata and B. angustifolia. Invertebrates were primarily responsible for seed removal of both species, although peak season of removal and microsite varied with species. Removal of seeds, emergence, and establishment increased with seed density. Matrix modeling indicated that population growth of C. fasciculata was greater in degraded habitat and greatest in litter microsites, and population growth of B. angustifolia was similar between habitats and greatest in bare sand. Contrasting responses among species to environmental factors in intact and degraded scrub indicated that natural disturbances are not ecologically equivalent to anthropogenic disturbances. Idiosyncratic species dynamics in common environments suggest that understanding relationships between life-history traits and environmental conditions will be required to facilitate restoration.
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Date Issued: 2013
Identifier: CFE0004754, ucf:49791
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0004754

Title: INTEGRAL PROJECTION MODELS REVEAL INTERACTIVE EFFECTS OF BIOTIC FACTORS AND DISTURBANCE ON PLANT DEMOGRAPHY.
Creator: Tye, Matthew, Quintana-Ascencio, Pedro, Fauth, John, Nevai, Andrew, Menges, Eric, University of Central Florida
Abstract / Description: Understanding factors limiting population growth is crucial to evaluating species persistence in changing environments. I used Integral Projection Models (IPMs) to elucidate the role of biotic interactions and disturbance on population growth rate in two plants: Helianthemum squamatum, a perennial endemic to gypsum habitats in central Spain, and Liatris ohlingerae, a long-lived perennial endemic to the Lake Wales Ridge of central Florida. In H. squamatum, there was a strong positive effect of...
Show moreUnderstanding factors limiting population growth is crucial to evaluating species persistence in changing environments. I used Integral Projection Models (IPMs) to elucidate the role of biotic interactions and disturbance on population growth rate in two plants: Helianthemum squamatum, a perennial endemic to gypsum habitats in central Spain, and Liatris ohlingerae, a long-lived perennial endemic to the Lake Wales Ridge of central Florida. In H. squamatum, there was a strong positive effect of trampling in the site with the highest plant density and moderate positive effects of seed addition in the site with the lowest plant density. Differences in treatment effectiveness between sites may represent a shift from seed to microsite limitation at increasing densities. Additionally, a distinct drop in population growth rate occurred in the hottest and driest year (2009-10). In Liatris ohlingerae, roadside populations had consistently higher population growth rates than scrub populations. A modest negative effect of time-since-fire was observed in plants that did not experience herbivory. Both habitat and time-since-fire showed distinct interactions with vertebrate herbivory, with herbivory increasing the difference in growth rate between habitats and decreasing the difference between time-since-fire classes. The direct effect of herbivory was negative in all environmental combinations except in long unburned populations. These results demonstrate the importance of considering environmental interactions when constructing population models, as well as the validity of using IPMs to assess interactions in species with differing life histories.
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Date Issued: 2014
Identifier: CFE0005271, ucf:50558
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0005271

Title: Accommodating Exogenous Variable and Decision Rule Heterogeneity in Discrete Choice Models: Application to Bicyclist Route Choice.
Creator: Dey, Bibhas, Eluru, Naveen, Abdel-Aty, Mohamed, Anowar, Sabreena, University of Central Florida
Abstract / Description: The thesis contributes to our understanding of incorporating heterogeneity in discrete choice models with respect to exogenous variables and decision rules. Specifically, we evaluate latent segmentation based mixed models that allow for segmenting population based on decision rules while also incorporating unobserved heterogeneity within the segment level decision rule models. In our analysis, we choose to consider the random utility framework along with random regret minimization approach....
Show moreThe thesis contributes to our understanding of incorporating heterogeneity in discrete choice models with respect to exogenous variables and decision rules. Specifically, we evaluate latent segmentation based mixed models that allow for segmenting population based on decision rules while also incorporating unobserved heterogeneity within the segment level decision rule models. In our analysis, we choose to consider the random utility framework along with random regret minimization approach. Further, instead of assuming the number of segments (as 2), we conduct an exhaustive exploration with multiple segments across the two decision rules. Within each segment we also allow for unobserved heterogeneity. The model estimation is conducted using a stated preference data from 695 commuter cyclists compiled through a web-based survey. The probabilistic allocation of respondents to different segments indicates that female commuter cyclists are more utility oriented, however the majority of the commuter cyclist's choice pattern is consistent with regret minimization mechanism. Overall, cyclists' route choice decisions are influenced by roadway attributes, cycling infrastructure availability, pollution exposure, and travel time. The analysis approach also allows us to investigate time based trade-offs across cyclists of different classes. Interestingly, we observed that the trade-off values in regret and utility based segments for roadway attributes are similar in magnitude; but the values differ greatly for cycling infrastructure and exposure attributes, particularly for maximum exposure levels.
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Date Issued: 2018
Identifier: CFE0007398, ucf:52059
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0007398

Title: The Effect of Registered Nurse Supply on Population Health Outcomes: A Distributed Lag Model Approach.
Creator: Sampson, Carla Jackie, Unruh, Lynn, Malvey, Donna, Liu, Albert Xinliang, Neff, Donna, University of Central Florida
Abstract / Description: Registered nurses (RNs) are essential to providing care in the healthcare system. To date, research on the relationship between healthcare provider supply and population health has focused on physician supply. This study explored the effect of RN supply on population health outcomes in the U.S. This is a retrospective, cross-sectional study of U.S. counties and county equivalents using national data. Seven population health outcomes (total and disease specific mortalities and low infant birth...
Show moreRegistered nurses (RNs) are essential to providing care in the healthcare system. To date, research on the relationship between healthcare provider supply and population health has focused on physician supply. This study explored the effect of RN supply on population health outcomes in the U.S. This is a retrospective, cross-sectional study of U.S. counties and county equivalents using national data. Seven population health outcomes (total and disease specific mortalities and low infant birth weight rate) were the response variables. The predictor variable, RN supply, and some control variables were anticipated to have an asynchronous effect on the seven outcome variables in the hypothesized relationship. Therefore, these variables were examined using three different models: contemporaneous; a three-year lagged; and a distributed lag (both contemporaneous and lagged variables). Quadratic terms for RN and physician supply variables were included. Because the Area Health Resource File (AHRF) outcome variables were skewed toward zero and left censored, Tobit regression analyses were used. Data were obtained from 19 states using historical RN Supply data for 1,472 counties, representing 47% of the total target population of 3,108 U.S. counties and county equivalents. Regions with rural populations(-)the Midwest and Southeast(-)were overrepresented. Higher RN supply is positively related to higher mortality rates from ischemic heart disease, other cardiovascular disease, and chronic lower respiratory disease in the distributed lag models. Higher RN supply is not significantly related to rates of low infant birth weight, infant mortality, or mortality from cerebrovascular disease in any model. Higher RN supply is positively related to total deaths in the contemporaneous and lagged model. The results suggest a counter-intuitive, but non-linear relationship between RN supply and health outcomes. More research is needed to understand these relationships and policies must be devised to reduce the current and growing future RN shortage.
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Date Issued: 2018
Identifier: CFE0007091, ucf:51933
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0007091

Title: A COMPARATIVE INVESTIGATION OF CAREER READINESS AND DECIDEDNESS IN FIRST YEAR STEM MAJORING STUDENTS PARTICIPATING IN A STEM MENTORING PROGRAM IMBEDDED IN A LIVING-LEARNING COMMUNITY WITH FOCUSED DATA ON FEMALE STEM STUDENTS.
Creator: Ramlakhan, Nirmala, Jeanpierre, Bobby, Boote, David, Hynes, Michael, Daire, Andrew, University of Central Florida
Abstract / Description: Female mentoring success was investigated as an undergraduate intervention utilizing career development practices to reduce dysfunctional career thinking and STEM major retention in first year freshmen females within a living-learning community. Repeated measures MANOVAs and canonical correlations in the causal comparative research design evaluated mentoring's influence on first year females. Male voluntary participants (n = 126) formulated the comparison group, and female voluntary...
Show moreFemale mentoring success was investigated as an undergraduate intervention utilizing career development practices to reduce dysfunctional career thinking and STEM major retention in first year freshmen females within a living-learning community. Repeated measures MANOVAs and canonical correlations in the causal comparative research design evaluated mentoring's influence on first year females. Male voluntary participants (n = 126) formulated the comparison group, and female voluntary participants (n = 75) filled the treatment group. Repeated measure multivariate analyses of variances compared differences between the interaction of mentoring and gender over time on dysfunctional career thinking using two assessments: Career Thoughts Inventory (CTI) and Career Decision Scale (CDS) and their five subscales (decision-making confusion, commitment anxiety, external conflict, certainty and indecision). Canonical correlations analyzed the effect participation rates had on student change scores on the CTI and CDS, indicating mentoring intervention effects on reducing dysfunctional career thinking and decidedness. Conclusions included: (a) females had higher levels of dysfunctional career thinking than males; (b) overtime both groups decreased dysfunctional thoughts,and solidifying their STEM career choices; (c) females had reduced levels of career decidedness compared to males; (d) both groups increased certainty overtime, solidifying their STEM career choice, and (e) when the STEM career choice was made, female certainty was more solidified than males. The study adds to the career development research within STEM at the undergraduate level providing colleges and universities with a structured first year female mentoring program in STEM. The GEMS model may be ideal for colleges and universities utilizing living-learning communities to increase underrepresented female retention and those without STEM career planning courses.?
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Date Issued: 2012
Identifier: CFE0004586, ucf:49191
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0004586

Title: THE EFFECTS OF DELAY OF GRATIFICATION ON THE ACADEMIC ACHIEVEMENT, SUBSTANCE ABUSE, and VIOLENT BEHAVIOR OF MIDDLE-SCHOOL STUDENTS IN ALTERNATIVE LEARNING SETTINGS.
Creator: Herndon, John, Gill, Michele, University of Central Florida
Abstract / Description: This study examined the effects of delay of gratification on academic success, substance abuse, and violent behavior. The participants in this study were chosen from an alternative learning school comprised of middle school students in Florida. The hypothesis for this study is as follows: Delay of gratification is negatively related to substance abuse and violent behavior, and positively related to academic achievement. The analysis of the data was conducted on the primary predictor variable ...
Show moreThis study examined the effects of delay of gratification on academic success, substance abuse, and violent behavior. The participants in this study were chosen from an alternative learning school comprised of middle school students in Florida. The hypothesis for this study is as follows: Delay of gratification is negatively related to substance abuse and violent behavior, and positively related to academic achievement. The analysis of the data was conducted on the primary predictor variable (delay of gratification), alternate predictor variables (substance abuse and violent behavior) and the ultimate outcome variable (academic achievement) of this study. Initial statistical inquiry involved descriptive statistics (mean, standard deviation, kurtosis and skew) of the aforementioned variables, partial correlations (variable interrelationships), and the formulation of a multiple regression path analysis to investigate the particular paths individually within the proposed theoretical model (Wagner, 1993).
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Date Issued: 2011
Identifier: CFE0003756, ucf:48790
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0003756

Title: Local Health Department Adoption of Health Information Technology and Its Impact on Population Health.
Creator: Yeung, Tina, Wan, Thomas, Cortelyou-Ward, Kendall, Liu, Albert Xinliang, Dziegielewski, Sophia, University of Central Florida
Abstract / Description: Since the enactment of the HITECH Act in 2009, the US has invested billions in building a robust health information technology (HIT) infrastructure that is secure, capable of the electronic transfer of data and allows for real-time access of patient medical data, among others. This empirical study explored the driving forces (coercive, mimetic, and normative) in the adoption of HIT (i.e. EHRs and HIEs) by local health departments (LHDs) and how it has impacted the population health of...
Show moreSince the enactment of the HITECH Act in 2009, the US has invested billions in building a robust health information technology (HIT) infrastructure that is secure, capable of the electronic transfer of data and allows for real-time access of patient medical data, among others. This empirical study explored the driving forces (coercive, mimetic, and normative) in the adoption of HIT (i.e. EHRs and HIEs) by local health departments (LHDs) and how it has impacted the population health of counties in the US. The researcher conducted a cross-sectional, quantitative study using secondary data sources. The study included data on 505 local health departments and 433 counties' population health data. Institutional theory guided this research and generalized estimating equations, logistic regression, and multiple linear regression were utilized to analyze health IT adoption by LHDs and its impact on county-level health outcomes. Results showed that normative forces, measured by the employment of IS specialists was most impactful in the adoption of both EHRs and HIEs. Mimetic forces, measured by the completion of a CHA and coercive forces measured by the implementation of the HITECH Act were not found to be statistically significant in the adoption of EHRs or HIEs. Finally, EHR adoption was statistically significant at improving population health at the county level. This research study has contributed in three areas: 1) to fill a knowledge gap on the impact of health IT adoption by LHDs on health outcomes; 2) to formulate a theoretically grounded framework to study population health and its variability; and 3) to identify target areas for public health interventions. In conclusion, a substantial amount of resources dedicated in creating a robust health IT infrastructure requires close analysis of the impact health IT has on the population health of our nation.
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Date Issued: 2017
Identifier: CFE0006825, ucf:51801
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0006825

Title: THE DEVELOPMENT OF AN EFFECTIVE RECRUITMENT STRATEGY FOR HISPANIC MALES AND FEMALES IN THE CENTRAL FLORIDA REGION.
Creator: Zeballos, Barbara, Rockmore, Benjamin, University of Central Florida
Abstract / Description: This study examines the similarities and differences between males and females from the Hispanic and Non-Hispanic White population in the Central Florida labor force regarding recruitment strategies and techniques of the Baby Boomers, Generation X and the Millennial population. The purpose of this study is to identify those Human Resources recruitment practices that are most effective in retaining: (1) males and females from the Hispanic population, and (2) whether or not theses recruitment...
Show moreThis study examines the similarities and differences between males and females from the Hispanic and Non-Hispanic White population in the Central Florida labor force regarding recruitment strategies and techniques of the Baby Boomers, Generation X and the Millennial population. The purpose of this study is to identify those Human Resources recruitment practices that are most effective in retaining: (1) males and females from the Hispanic population, and (2) whether or not theses recruitment tactics affect the generation groups differently. The proposed issues will be assessed by collecting information from organizations, current employees, and job applicants. This study will use three research methods in addressing the stated purpose and objectives: literature review, focus groups, and questionnaire surveys. The literature review will explore present recruitment techniques, social and cultural similarities and differences between Hispanics and Non-Hispanic White, and generational differences. The main goal of the focus groups is to identify relevant recruitment issues as stated by Central Florida organizations, current employees, and job applicants. From the literature review and results of the focus groups two surveys will be develop to determine: (1) present recruitment practices used by Central Florida organizations; and (2) preferred recruitment practices among Hispanics and Non-Hispanic Whites. The results of this study will identify whether certain recruitment practices perceived as being most appealing and desirable vary among Hispanics and Non-Hispanic Whites. Based on the findings, the study will provide recommendations for designing effective recruitment strategies for Hispanic and Non-Hispanic White males and females while accounting for possible generational differences.
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Date Issued: 2011
Identifier: CFH0004061, ucf:44789
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFH0004061

Title: Assessing the Impact of Economies of Scale and Uncontrollable Factors on the Performance of U.S. Cities.
Creator: Allaf, Mamoon, Martin, Lawrence, Wan, Thomas, Kapucu, Naim, Baker, Paul, University of Central Florida
Abstract / Description: Despite the increased interest among local governments in collecting data on performance measurement, empirical evidence is still limited regarding the extent to which these data are utilized to assess the impact on efficiency of economies of scale and uncontrollable factors. Data envelopment analysis (DEA) is a linear programming method designed to estimate the relative efficiency of decision-making units. In addition to assessing relative efficiency, DEA can estimate scale efficiency and...
Show moreDespite the increased interest among local governments in collecting data on performance measurement, empirical evidence is still limited regarding the extent to which these data are utilized to assess the impact on efficiency of economies of scale and uncontrollable factors. Data envelopment analysis (DEA) is a linear programming method designed to estimate the relative efficiency of decision-making units. In addition to assessing relative efficiency, DEA can estimate scale efficiency and incorporate the impact of uncontrollable factors. Using data from the International City/County Association (ICMA), this study utilized DEA to evaluate the impact of economies of scale and uncontrollable factors on the relative efficiency of municipal service delivery in the United States. The findings from this doctoral dissertation show that uncontrollable variables such as population density, unemployment, and household income suppress the relative efficiency of local governments. Moreover, the findings imply that the prevalence of economies of scale in city governments depends on the types of services these governments provide.
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Date Issued: 2012
Identifier: CFE0004201, ucf:49002
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0004201

Title: L2 ANXIETY IN SPANISH-SPEAKING ADULT ESL POPULATIONS: POSSIBLE CAUSES AND CULTURAL INFLUENCES.
Creator: Freiberger, Scott, Mihai, Florin, University of Central Florida
Abstract / Description: Anxiety has been identified as a plausible factor affecting second language (L2) acquisition. However, more research is needed on how anxiety may influence Spanish-speaking adult English as a Second Language (ESL) populations. Determining precisely what causes anxiety in Spanish-speaking adult ESL populations should be of interest not only to L2 researchers but also to ESL instructors who may have adult Spanish-speaking English language learners (ELLs) in their classes. This study researched...
Show moreAnxiety has been identified as a plausible factor affecting second language (L2) acquisition. However, more research is needed on how anxiety may influence Spanish-speaking adult English as a Second Language (ESL) populations. Determining precisely what causes anxiety in Spanish-speaking adult ESL populations should be of interest not only to L2 researchers but also to ESL instructors who may have adult Spanish-speaking English language learners (ELLs) in their classes. This study researched L2 anxiety in Spanish-speaking adult ESL learners. Specifically, it considered possible causes and cultural influences of L2 anxiety in 10 Spanish-speaking adult ESL students at a university English language institute (ELI). Participants were given a choice of completing an English or Spanish version of the Foreign Language Classroom Anxiety Scale (FLCAS) and then participated in follow-up interviews. Results were documented and evaluated. A total of 14 causes of L2 anxiety were identified, including incompatible goals, using English in professional contexts, the native country, and the need for error correction. Finally, contrary to the literature, collaborative group work was found to cause L2 anxiety in Spanish-speaking adult ESL students enrolled at a language institute.
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Date Issued: 2010
Identifier: CFE0003050, ucf:48364
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0003050

Title: Reexamining the Relationship Between Divided Government and Voter Turnout.
Creator: Beck, Heidi, Knuckey, Jonathan, Jewett, Aubrey, Lanier, Drew, University of Central Florida
Abstract / Description: This thesis reexamines the effect of divided government on voter turnout originally posited byFranklin and Hirczy de Mi(&)#241;o (1998), which suggested that each year of exposure to dividedgovernment resulted in a cumulative negative effect on voters leading to alienation and lowerturnout. It reconsiders this argument using more recent data, given that voter turnout in U.S.presidential elections (as measured by the Voting Eligible Population) has increased since 2000,even though divided...
Show moreThis thesis reexamines the effect of divided government on voter turnout originally posited byFranklin and Hirczy de Mi(&)#241;o (1998), which suggested that each year of exposure to dividedgovernment resulted in a cumulative negative effect on voters leading to alienation and lowerturnout. It reconsiders this argument using more recent data, given that voter turnout in U.S.presidential elections (as measured by the Voting Eligible Population) has increased since 2000,even though divided government has occurred during this period.This thesis also uses new data and methods to address concerns about the original aggregatelevelresearch design. The research question is tested at the individual-level of analysis todetermine if divided government does interact with political trust to lower turnout. Previousresearch assumed this relationship since there is no aggregate-level proxy for political trust. Byusing survey data from the American National Election Studies it is now possible to test the fulltheory.The aggregate-level models show that misspecifications in the research design of Franklinand Hirczy de Mi(&)#241;o resulting in multicollinearity, and in two instances autocorrelation, whichresulted in a failure to reject the null hypothesis. The individual-level models show that dividedgovernment interacts with low levels of political trust to increase voter turnout, falsifying theargument about the effect of divided government on turnout. Overall, the thesis suggests that theimplications of an aspect of the American political system that renders it distinguishable frommost other advanced-industrial democracies(-)divided party control of the executive andlegislative branches(-)should be reassessed. More generally, the thesis demonstrates theimportance of reevaluating hypotheses in political science with the most recent data and morerobust methods in order to establish whether those original hypotheses are still supported
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Date Issued: 2019
Identifier: CFE0007783, ucf:52363
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0007783

Title: A mathematical model for feral cat ecology with application to disease.
Creator: Sharpe, Jeff, Nevai, A, Shuai, Zhisheng, Qi, Yuanwei, Quintana-Ascencio, Pedro, University of Central Florida
Abstract / Description: We formulate and analyze a mathematical model for feral cats living in an isolated colony. The model contains compartments for kittens, adult females and adult males. Kittens are born at a rate proportional to the population of adult females and mature at equal rates into adult females and adult males. Adults compete with each other in a manner analogous to Lotka-Volterra competition. This competition comes in four forms, classified by gender. Native house cats, and their effects are also...
Show moreWe formulate and analyze a mathematical model for feral cats living in an isolated colony. The model contains compartments for kittens, adult females and adult males. Kittens are born at a rate proportional to the population of adult females and mature at equal rates into adult females and adult males. Adults compete with each other in a manner analogous to Lotka-Volterra competition. This competition comes in four forms, classified by gender. Native house cats, and their effects are also considered, including additional competition and abandonment into the feral population. Control measures are also modeled in the form of per-capita removal rates. We compute the net reproduction number (R_0) for the colony and consider its influence. In the absence of abandonment, if R_0(>)1, the population always persists at a positive equilibrium and if R_0 (<)= 1, the population always tends toward local extinction. This work will be referred to as the core model.The model is then expanded to include a set of colonies (patches) such as those in the core model (this time neglecting the effect of abandonment). Adult females and kittens remain in their native patch while adult males spend a fixed proportion of their time in each patch. Adult females experience competition from both the adult females living in the same patch as well as the visiting adult males. The proportion of adult males in patch j suffer competition from both adult females resident to that patch as well the proportion of adult males also in the patch. We formulate a net reproduction number for each patch (a patch reproduction number) R_j. If R_j(>)1 for at least one patch, then the collective population always persists at some nontrivial (but possibly semitrivial) steady state. We consider the number of possible steady states and their properties. This work will be referred to as the patch model.Finally, the core model is expanded to include the introduction of the feline leukemia virus. Since this disease has many modes of transmission, each of which depends on the host's gender and life-stage, we regard this as a model disease. A basic reproduction number R_0 for the disease is defined and analyzed. Vaccination terms are included and their role in disease propagation is analyzed. Necessary and sufficient conditions are given under which the disease-free equilibrium is stable.
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Date Issued: 2016
Identifier: CFE0006502, ucf:51389
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0006502

Title: Habitat selection in transformed landscapes and the role of novel ecosystems for native species persistence.
Creator: Sanchez Clavijo, Lina, Quintana-Ascencio, Pedro, Noss, Reed, Weishampel, John, Rodewald, Amanda, University of Central Florida
Abstract / Description: To understand native species persistence in transformed landscapes we must evaluate how individual behaviors interact with landscape structure through ecological processes such as habitat selection. Rapid, widespread landscape transformation may lead to a mismatch between habitat preference and quality, a phenomenon known as ecological traps that can have negative outcomes for populations. I applied this framework to the study of birds inhabiting landscapes dominated by forest remnants and...
Show moreTo understand native species persistence in transformed landscapes we must evaluate how individual behaviors interact with landscape structure through ecological processes such as habitat selection. Rapid, widespread landscape transformation may lead to a mismatch between habitat preference and quality, a phenomenon known as ecological traps that can have negative outcomes for populations. I applied this framework to the study of birds inhabiting landscapes dominated by forest remnants and shade coffee plantations, a tropical agroforestry system that retains important portions of native biodiversity. I used two different approaches to answer the question: What is the role of habitat selection in the adaptation of native species to transformed landscapes? First, I present the results of a simulation model used to evaluate the effects of landscape structure on population dynamics of a hypothetical species under two mechanisms of habitat selection. Then I present the analyses of seven years of capture-mark-recapture and resight data collected to compare habitat preference and quality between shade coffee and forest for twelve resident bird species in the Sierra Nevada de Santa Marta (Colombia). I provide evidence for the importance of including the landscape context in the evaluation of ecological traps and for using long-term demographic data when evaluating the potential of novel ecosystems and intermediately-modified habitats for biodiversity conservation. Beyond suggestions to improve bird conservation in shade coffee, my findings contribute to theory about ecological traps and can be applied to understand population processes in a wide variety of heterogeneous landscapes.
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Date Issued: 2016
Identifier: CFE0006494, ucf:51392
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0006494

Title: Dimensions of State Fragility: Determinants of Violent Group Grievance, Political Legitimacy, (&) Economic Capacity.
Creator: Christensen, Jason, Kinsey, Barbara, Mousseau, Demet, Hamann, Kerstin, Kircher, Amy, University of Central Florida
Abstract / Description: State fragility has severe political implications. In the literature, fragile states have been referred to as (")chaotic breeding grounds(") for human rights violations, terrorism, violent extremism, crime, instability, and disease (Patrick 2011, 3-4). International organizations have also expressed concern regarding the potential of (")fragile states(") to disrupt collective security as threats such as transnational terrorism and human displacement from violent conflict have the potential to...
Show moreState fragility has severe political implications. In the literature, fragile states have been referred to as (")chaotic breeding grounds(") for human rights violations, terrorism, violent extremism, crime, instability, and disease (Patrick 2011, 3-4). International organizations have also expressed concern regarding the potential of (")fragile states(") to disrupt collective security as threats such as transnational terrorism and human displacement from violent conflict have the potential to permeate borders (Patrick 2011, 5). This research project aims at extending our understanding of state fragility by examining three distinct dimensions of state fragility proposed in the literature: i) state authority, ii) state legitimacy, and iii) state capacity. I narrow the scope of these dimensions by focusing on 1) violent group grievance, 2) political legitimacy, and 3) state economic capacity, respectively. The first dimension, state authority, is related to a government's control of unlawful intrastate violence. The second dimension, legitimacy, is linked to the public acceptance of the right of an authority to govern law through its practice and influence (Weber 1958, 32-36; Gilley 2006, 48; Connolly 1984, 34). The third dimension, capacity, represents a state-society relationship characterized mainly by the state's ability to provide public goods and protection of citizens and residents from (")harm(") such as natural disasters and economic downfalls (Gr(&)#228;vingholt, Ziaja, and Kreibaum 2012, 7). This dissertation examines each of these dimensions using quantitative analyses based on large-N datasets and cross-sectional longitudinal models to fill gaps in the literature on state fragility. In particular, I hypothesize 1) number of refugees increases the level of intrastate violent group grievance (state authority), 2) state human rights violations decreases popular support and thus public perceptions of state legitimacy, and 3) population constraints, such as food insecurity and disease increase economic decline and thus compromise the state's economic capacity. Internal violence, loss of legitimacy, and a weakened economy may increase levels of state fragility. Each of these three studies controls for alternative explanations and covers the time period between 2006 and 2014. The analysis results confirm the main hypotheses of this study and are expected to offer a more concise conceptual framework of state fragility, and better empirical understanding of potential contributors to state fragility.
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Date Issued: 2017
Identifier: CFE0006728, ucf:51876
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0006728

Title: Middle Grades Science in Florida: A Comparison of Student Achievement in Comprehensive and Subject-specific Science Courses 2013-2017.
Creator: Moore, Kenneth, Taylor, Rosemarye, Baldwin, Lee, Storey, Valerie A., Gao, Su, University of Central Florida
Abstract / Description: As with U.S. student achievement on national and international science assessments, Florida's 8th grade student achievement on the 2013(-)2017 8th grade Florida Comprehensive Assessment Test (FCAT) 2.0 Science/Statewide Science Assessment (SSA) was stagnant. To break this stagnation, many Florida school districts have changed middle grades science course offerings from traditional, subject-specific, discipline-based, layered, or field-specific science courses to comprehensive, integrated,...
Show moreAs with U.S. student achievement on national and international science assessments, Florida's 8th grade student achievement on the 2013(-)2017 8th grade Florida Comprehensive Assessment Test (FCAT) 2.0 Science/Statewide Science Assessment (SSA) was stagnant. To break this stagnation, many Florida school districts have changed middle grades science course offerings from traditional, subject-specific, discipline-based, layered, or field-specific science courses to comprehensive, integrated, spiraled, interdisciplinary, multidisciplinary, thematic, or general science courses. There was a lack of research showing if either type of science course improved student achievement on standardized science assessments. Controlling for school district student population, low socio-economic status (SES) student percentage, and English learner (EL) percentage, this study compared the 2013(-)2017 8th grade FCAT 2.0 Science/SSA school district mean scale scores of two groups of school districts: those that offered comprehensive science courses and those that offered subject-specific science courses. Scores for three student groups were analyzed: all students, low SES students, and ELs. No statistically significant differences were found in school district mean scale scores or pass rates between the two school district groups. The comprehensive group mean scale scores were numerically higher, while the subject-specific group mean pass rates were numerically higher. The subject-specific group had statistically significantly higher raw scores for life science and physical science. The comprehensive group had wider dispersions of mean scale scores and pass rates, suggesting inconsistencies in implementation of comprehensive science courses. The primary implication of this study is that educational leaders should not expect to improve student science achievement simply by changing the type of science course offering. Changes should be made with consideration to student needs, school district demographics, teacher professional development and support, course structure and coherence with standards, and the need for flexibility in teacher assignments.
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Date Issued: 2018
Identifier: CFE0007410, ucf:52710
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0007410

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