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Partnership for Building Institutional/National Capacity: Addis Ababa University and University of North Texas Initiatives
Presentation for the 2015 International Conference on Information Communication Technologies (ICT) for Development, Education, and Training. This presentation discusses partnerships for building institutional/national capacity and initiatives at Addis Ababa University and the University of North Texas.
Date:
May 2015
Creator:
Abate, Solomon Teferra & Alemneh, Daniel Gelaw
Object Type:
Presentation
System:
The UNT Digital Library
Interfacial Characterization of Chemical Vapor Deposition (Cvd) Grown Graphene and Electrodeposited Bismuth on Ruthenium Surface
Graphene receives enormous attention owing to its distinctive physical and chemical prosperities. Growing and transferring graphene to different substrates have been investigated. The graphene growing on the copper substrate has an advantage of low solubility of carbon on the copper which allow us to grow mostly monolayer graphene. Graphene sheet of few centimeters can be transferred to 300nm silicon oxide and quartz crystal pre-deposited with metal like Cu and Ru. Characterization of the graphene has been done with Raman and contact angle measurement and recently quartz crystal microbalance (QCM) has been employed. The underpotential deposition (UPD) process of Bi on Ru metal surface is studied using electrochemical quartz crystal microbalance (EQCM) and XPS techniques. Both Bi UPD and Bi bulk deposition are clearly observed on Ru in 1mM Bi (NO3)3/0.5M H2SO4. Bi monolayer coverage calculated from mass (MLMass) and from charge (MLCharge) were compared with respect to the potential scanning rates, anions and ambient controls. EQCM results indicate that Bi UPD on Ru is mostly scan rate independent but exhibits interesting difference at the slower scan. Bi UPD monolayer coverage calculated from cathodic frequency change (ΔfCathodic) is significantly smaller than the monolayer coverage derived from integrated charge under the cathodic …
Date:
May 2014
Creator:
Abdelghani, Jafar
Object Type:
Thesis or Dissertation
System:
The UNT Digital Library
Derivation of the Thematic Material and Intervallic Gestures From the Main Theme in Fantasia Carioca By Sérgio Assad
The quantity of classical guitar literature reached a new peak late in the twentieth century with many famous guitarists publishing their own works for solo classical guitar. This increase in the published guitar literature resulted in a decline of the relative analytical discussions of contemporary guitar works. Sérgio Assad is a perfect example of an active guitarist/composer whose works are frequently performed in guitar recitals and yet very little discussion has been provided attempting to gain a deeper understanding of his compositional language. The purpose of this study is to two-fold: first, to show that Fantasia Carioca (1994) is a very carefully organized work and includes an intricate network of thematic material developed through a spectrum of intervallic gestures, of which all derive from the main theme of the piece; second, to provide a deeper insight into the compositional language of Sérgio Assad through a demonstration of different compositional procedures to which the composer resorts. This one-movement piece reveals a high level of organization present in Sérgio Assad's style. The entire thematic material is carefully derived from the main theme. Each thematic unit shows a set of predetermined characteristics that allow these units to react to particular textures and situations. …
Date:
May 2013
Creator:
Abdihodži?, Armin
Object Type:
Thesis or Dissertation
System:
The UNT Digital Library
Field Validation of Zero Energy Lab Water-to-Water Ground Coupled Heat Pump Model
Heat pumps are a vital part of each building for their role in keeping the space conditioned for the occupant. This study focuses on developing a model for the ground-source heat pump at the Zero Energy lab at the University of North Texas, and finding the minimum data required for generating the model. The literature includes many models with different approaches to determine the performance of the heat pump. Each method has its pros and cons. In this research the equation-fit method was used to generate a model based on the data collected from the field. Two experiments were conducted for the cooling mode: the first one at the beginning of the season and the second one at the peak of the season to cover all the operation conditions. The same procedure was followed for the heating mode. The models generated based on the collected data were validated against the experiment data. The error of the models was within ±10%. The study showed that the error could be reduced by 20% to 42% when using the field data to generate the model instead of the manufacturer’s catalog data. Also it was found that the minimum period to generate the cooling …
Date:
May 2016
Creator:
Abdulameer, Saif
Object Type:
Thesis or Dissertation
System:
The UNT Digital Library
Jacques-Antoine-Hippolyte, comte de Guibert: Father of the Grande Armée
The eighteenth century was a time of intense upheaval in France. The death of Louis XIV in 1715 and the subsequent reign of Louis XV saw the end of French political and martial hegemony on the continent. While French culture and language remained dominant in Europe, Louis XV's disinterested rule and military stagnation led to the disastrous defeat of the French army at the hands of Frederick the Great of Prussia in the Seven Years War (1756-1763). The battle of Rossbach marked the nadir of the French army in the Seven Years War. Frederick's army routed the French infantry that had bumbled its way into massed Prussian cavalry. Following the war, two reformist elements emerged in the army. Reformers within the government, chiefly Etienne François, duc de Choiseul, sought to rectify the army's poor performance and reconstitute France's military establishment. Outside the traditional army structure, military thinkers looked to military theory to reinvigorate the army from within and without. Foremost among the latter was a young officer named Jacques-Antoine-Hippolyte de Guibert, whose 1772 Essai général de tactique quickly became the most celebrated work of theory in European military circles. The Essai provided a new military constitution for France, proposing wholesale …
Date:
May 2011
Creator:
Abel, Jonathan, 1985-
Object Type:
Thesis or Dissertation
System:
The UNT Digital Library
Source Apportionment Analysis of Measured Volatile Organic Compounds in Corpus Christi, Texas
Corpus Christi among of the largest industrialized coastal urban areas in Texas. The strategic location of the city along the Gulf of Mexico allows for many important industries and an international business to be located. The cluster of industries and businesses in the region contribute to the air pollution from emissions that are harmful to the environment and to the people living in and visiting the area. Volatile organic compounds (VOC) constitute an important class of pollutants measured in the area. The automated gas chromatography (Auto GC) data was collected from Texas Commission of Environmental Quality (TCEQ) and source apportionment analysis was conducted on this data to identify key sources of VOC affecting this study region. EPA PMF 3.0 was employed in this sources apportionment study of measured VOC concentration during 2005 - 2012 in Corpus Christi, Texas. The study identified nine optimal factors (Source) that could explain the concentration of VOC at two urbane monitoring sites in the study region. Natural gas was found to be the largest contributor of VOC in the area, followed by gasoline and vehicular exhaust. Diesel was the third highest contributor with emissions from manufacturing and combustion processes. Refineries gases and evaporative fugitive emissions …
Date:
May 2014
Creator:
Abood, Ahmed T.
Object Type:
Thesis or Dissertation
System:
The UNT Digital Library
Development of a Cost Effective Wireless Sensor System for Indoor Air Quality Monitoring Applications
Poor air quality can greatly affect the public health. Research studies indicate that indoor air can be more polluted than the outdoor air. An indoor air quality monitoring system will help to create an awareness of the quality of air inside which will eventually help in improving it. The objective of this research is to develop a low cost wireless sensor system for indoor air quality monitoring. The major cost reduction of the system is achieved by using low priced sensors. Interface circuits had to be designed to make these sensors more accurate. The system is capable of measuring carbon dioxide, carbon monoxide, ozone, temperature, humidity and volatile organic compounds. The prototype sensor node modules were developed. The sensor nodes were the connected together by Zigbee network. The nodes were developed in such a way that it is compact in size and wireless connection of sensor nodes enable to collect air quality data from multiple locations simultaneously. The collected data was stored in a computer. We employed linear least-square approach for the calibration of each sensor to derive a conversion formula for converting the sensor readings to engineering units. The system was tested with different pollutants and data collected was …
Date:
May 2014
Creator:
Abraham, Sherin
Object Type:
Thesis or Dissertation
System:
The UNT Digital Library
Students' Attitudes toward Educational Gamification in Online Learning Environments
This study explored undergraduate and graduate students' attitudes toward the pleasurability of educational gamification in online learning environments. The study is a sequential explanatory mixed-methods research that investigated students' attitudes quantitatively, then qualitatively. In the quantitative phase, an online survey, the Pleasurable Learning Experiences scale (PLLEXs), was administrated at one of the largest public southwestern universities in the U.S. (N = 119). The qualitative phase involved conducting eight semi-structured interviews with selected participants. The PLLEXs uses a 4-point Likert scale that encompasses 4 subscales: (a) Preferences for Instructions, (b) Preferences for Instructors' Teaching Styles, (c) Preferences for Activities, and (d) Preferences for Learning Effectiveness. A series of analyses of variances (ANOVAs) were used to identify predictors of students' overall attitudes toward educational gamification. The main findings were: (a) students had strong preferences toward educational gamification with Preferences of Instructions rated the highest subscale and Preferences for Activities rated the lowest subscale, (b) major was a statistically significant predictor of students' attitudes toward educational gamification, (c) international students had statistically significant lower preferences toward educational gamification compared with U.S. domestic students, (c) online learning experiences measured by the number of previous online courses and the number of hours spent weekly on …
Date:
May 2019
Creator:
Abu Dawood, Sumayah Mohammadlutfi
Object Type:
Thesis or Dissertation
System:
The UNT Digital Library
Exploratory Analysis of Social E-health Behavior
Extant literature has documented well that people seek health information via the internet as patients and consumers. Much less, however, is known about interaction and creation behaviors in the development of new online health information and knowledge. More specifically, generalizable sociodemographic data on who engages in this online health behavior via social media is lacking in the sociological literature. The term “social e-health” is introduced to emphasize the difference between seeking behaviors and interaction and creation behaviors. A 2010 dataset of a large nationally representative and randomly sampled telephone survey made freely available from the Pew Research Center is used to examine social e-health behavior according to respondents’ sociodemographics. The dependent variable of social e-health behavior is measured by 13 survey questions from the survey. Gender, race, ethnicity, age, education, and income are used as independent variables. Logistic regression analysis was used to determine the odds of engagement in social e-health behavior based on the sociodemographic predictors. The social determinants of health and digital divide frameworks are used to help explain why socioeconomic variances exist in social e-health behavior. The findings of the current study suggest that predictable sociodemographic patterns along the dimensions of gender, race, age, education, and income …
Date:
May 2014
Creator:
Acadia, Spencer
Object Type:
Thesis or Dissertation
System:
The UNT Digital Library
The Relationship Between Supplemental Instruction Leader Learning Style and Study Session Design
The purpose of this qualitative study was to examine the learning styles of supplemental instruction leaders at a large, public university during the fall 2010 semester and determine whether or not their personal learning styles influenced the way they designed and developed out-of-class study sessions. The total population of supplemental instruction leaders was 37, of which 24 were eligible to participate in the study. Of the 24 eligible supplemental instruction leaders, 20 completed the entire study. Participants in the study included nine male and 11 female supplemental instruction leaders with a median age of 22.25 years-old. Seventeen participants indicated their classification as senior, two as junior, and one as sophomore. Of the participants, 16 indicated white as a race or ethnicity, one indicated Asian, two indicated African American, and one indicated both American Indian/Alaska Native and white. Supplemental instruction leader learning style was assessed using the Kolb Learning Style Inventory. Leaders were then interviewed, and their study sessions were analyzed. Through triangulation of data from learning style, interviews and actual study session documents, four major themes emerged. The four themes were: 1) incorporation of personal experience into study session design, 2) the sense of impact on student learning, 3) a …
Date:
May 2011
Creator:
Adams, Joshua
Object Type:
Thesis or Dissertation
System:
The UNT Digital Library
Solvent Effects and Bioconcentration Patterns of Antimicrobial Compounds in Wetland Plants
This study looked at effects of organic solvents dimethylsulfoxide, dimethylformamide and acetone at 0.01%, 0.05% and 0.1% concentration on germination and seedling development wetland plants. Even at 0.01% level, all solvents affected some aspect of seed germination or seedling growth. Acetone at 0.01% was least toxic. Root morphological characteristics were most sensitive compared to shoot morphological characteristics. This study also looked at bioconcentration patterns of antimicrobial compounds triclosan, triclocarban and methyl-triclosan in wetland plants exposed to Denton Municipal Waste Water Treatment Plant effluent. Bioconcentration patterns of antimicrobial compounds varied among species within groups as well as within organs of species. The highest triclocarban, triclosan and methyltriclosan concentration were in shoot of N. guadalupensis, root of N. lutea and in shoots of P. nodous respectively.
Date:
May 2011
Creator:
Adhikari, Sajag
Object Type:
Thesis or Dissertation
System:
The UNT Digital Library
Information Content of Non-GAAP Earnings of Cross-Listed Companies
To supplement earnings reported under generally accepted accounting principles (GAAP), public companies often voluntarily report alternative measures of earnings called non-GAAP earnings (NGE). These companies assert that NGE exclude the effect of non-recurring transactions, thereby helping users of financial information to better assess the company's past performance and prospects. Because NGE measures are not well defined, managers can exploit the inherent discretion in calculating NGE to mislead users. Prior studies provide arguments and evidence on the informative as well as opportunistic use of NGE. However, the studies have examined the characteristics and informativeness of NGE with a focus on U.S. companies. The results of studies that consider the NGE disclosure by U.S. companies may not be generalizable to the cross-listed companies because foreign financial reporting standards are different from the U.S. GAAP. Further, prior studies report a difference in earnings quality of U.S. firms and cross-listed firms, which can also result in a difference in the informativeness of their NGE. To fill this gap in literature, I examine whether the informativeness of NGE of cross-listed companies is different from that of U.S. companies. This study contributes to the debate on the informativeness of NGE. It provides evidence that in general, …
Date:
May 2018
Creator:
Adhikari, Subash
Object Type:
Thesis or Dissertation
System:
The UNT Digital Library
The Status and Challenges of Online Distance Education Programs in Post-Secondary Institutions in Ghana
The purpose of this study was to identify the status and challenges of online distance education programs in post-secondary institutions in Ghana. This study was a replication of a similar study conducted in Kenya in 2009, at the University of Nairobi and Kenyatta University. This present study was conducted with an online survey using Google survey assessment. The survey requested responses from six post-secondary institutions in Ghana. Out of a total of 450 projected student responses, 309 responses were received with a 69% participation rate. A total of 14 responses were received for instructors out of a projected 30 resulting in 47% participation rate. And for administrators, 8 responses were received out of a projected 12 resulting in a 67% participation rate. Overall the study revealed that Ghana post-secondary institutions have established and incorporated online distance education into their programs, offering both online and blended courses. Some of these institutions established regional centers across the country and incorporated foreign instructors into their programs. The survey also revealed that students were satisfied with the overall online distance education program in their institutions which included the level of instruction, feedback and evaluation. However, there were still challenges revealed from the study that …
Date:
May 2017
Creator:
Adjabeng, Stanley
Object Type:
Thesis or Dissertation
System:
The UNT Digital Library
Practical Evaluation of a Software Defined Cellular Network
This thesis proposes a design of a rapidly deployable cellular network prototype that provides voice and data communications and it is interoperable with legacy devices and the existing network infrastructure. The prototype is based on software defined radio and makes use of IEEE 802.11 unlicensed wireless radio frequency (RF) band for backhaul link and an open source GSM implementation software. The prototype is also evaluated in environments where there is limited control of the radio frequency landscape, and using Voice Over Internet Protocol (VoIP) performance metrics to measure the quality of service. It is observed that in environments where the IEEE 802.11 band is not heavily utilized, a large number of calls are supported with good quality of service. However, when this band is heavily utilized only a few calls can be supported as the quality of service rapidly degrades with increasing number of calls, which is due to interference. It is concluded that in order to achieve tolerable voice quality, unused licensed spectrum is needed for backhaul communication between base stations.
Date:
May 2017
Creator:
Agbogidi, Oghenetega
Object Type:
Thesis or Dissertation
System:
The UNT Digital Library
Instructional Personnel Perceptions on Integrating Instructional Technology in K-12 Classrooms: A Case Study
Integrating digital pedagogy into instruction in a manner that promotes critical thinking and drives increased student achievement and engagement in all classrooms is a goal of many campuses and districts that invest heavily in hardware, software, and professional development on an annual basis. Digital pedagogy goals tend to center around preparing students for the 21st century workforce, promoting instruction that is more engaging, and providing deeper learning for all students; however, achieving these goals is not possible without teachers willing and able to effectively implement instructional technology into the content they are teaching. The conceptual framework consists of digital leadership, teacher engagement, and resources and supports. This case study focused on the district-wide integration of technology into instruction through the elements found in the conceptual framework. Educators, from kindergarten through twelfth grade were surveyed about their attitudes, self-efficacy perceptions and willingness to integrate digital pedagogies into their current teaching practices. The online survey that utilized Likert-like scales to gather demographic information as well educator perceptions on digital integration, teaching philosophy, digital self-efficacy, and leadership's focus and expectations regarding instructional technology. Additional data, from a variety of district documents, was also gathered on leadership, professional development, and infrastructure supports utilized to …
Date:
May 2019
Creator:
Agent, Renee L
Object Type:
Thesis or Dissertation
System:
The UNT Digital Library
Family Structure and Marijuana Use Among Adolescents
Family structure as a predictive variable of juvenile delinquency has been studied for the last hundred years. This relationship originated due to societal belief that divorce was detrimental to adolescents. Due to the changing societal roles in the United States, family structure has been changing. More children are growing up in non-intact families, such as single-parent households, households with stepparents, cohabitating families, and households without a parent present. To study the effect family structure has on juvenile delinquency, researchers have utilized social control theory, differential association, self-control theory and general strain theory to conceptualize variables to explain why family structure influences delinquent behavior. A review of previous literature on this topic indicates that living in intact households, which are households with two biological parents who are married, have, on average, the lowest rates of delinquency. This thesis investigates the relationship between family structure and lifetime marijuana use among eighth and tenth grade adolescents in the United States through the use of secondary data analysis of Monitoring the Future Study, 2012. The results provide support for the relationship between family structure and lifetime marijuana use.
Date:
May 2014
Creator:
Aguilar, Jamie M.
Object Type:
Thesis or Dissertation
System:
The UNT Digital Library
Interpersonal Factors Related to the Pursuit of a Higher Education Among First Generation Undergraduate Students
The typical educational stressors experienced by college students, in conjunction with developmental stressors such as separation from parents, individuation, and perceived social support, can interact to impact adaptation significantly. First generation college students (students who are the first in their family to attend college) can experience stressors beyond the typical educational stressors experienced by later generation college students, including lack of support from family and peers as well as financial difficulties that can interact to impact the pursuit of an education beyond the undergraduate level. The present study examined factors that may be especially influential in the pursuit of a higher education for first generation college students. Results indicated that aspects of family enmeshment were related to academic motivation for first generation students, but not for later generation students. Exploratory analysis showed that family and finances were mentioned more often among first generation students when compared to later generation students as stressors that strongly influence the desire to continue beyond the undergraduate level.
Date:
May 2012
Creator:
Aguirre, Jacqueline S.
Object Type:
Thesis or Dissertation
System:
The UNT Digital Library
Ozone Pollution of Shale Gas Activities in North Texas
The effect of shale gas activities on ground-level ozone pollution in the Dallas-Fort Worth area is studied in detail here. Ozone is a highly reactive species with harmful effects on human and environment. Shale gas development, or fracking, involves activities such as hydraulic fracturing, drilling, fluid mixing, and trucks idling that are sources of nitrogen oxides (NOX) and volatile organic compounds (VOC), two of the most important precursors of ozone. In this study two independent approaches have been applied in evaluating the influences on ozone concentrations. In the first approach, the influence of meteorology were removed from ozone time series through the application of Kolmogorov-Zurbenko low-pass filter, logarithmic transformation, and subsequent multi-linear regression. Ozone measurement data were acquired from Texas Commission on Environmental Quality (TCEQ) monitoring stations for 14 years. The comparison between ozone trends in non-shale gas region and shale gas region shows increasing ozone trends at the monitoring stations in close proximity to the Barnett Shale activities. In the second approach, the CAMx photochemical model was used to assess the sensitivity of ozone to the NOX and VOC sources associated with shale oil and gas activities. Brute force method was applied on Barnett Shale and Haynesville Shale emission …
Date:
May 2016
Creator:
Ahmadi, Mahdi
Object Type:
Thesis or Dissertation
System:
The UNT Digital Library
General Satisfaction of Students in 100% Online Courses in the Department of Learning Technologies at the University of North Texas
The purpose of this study was to examine whether there are significant relationships between the general satisfaction of students and learner-content interaction, learner-instructor interaction, learner-learner interaction, and learner-technology interaction in 100% online courses. There were 310 responses from the students. This study did not use data from duplicate students and instructors. Excel was used to find duplicate students and instructors; therefore, 128 responses were deleted. After examination of box plots, an additional four cases were removed because they were outliers on seven or more variables. Nineteen responses were deleted because they did not answer all questions of interest, resulting in a total sample of 159 students. Multiple regression analysis was used to examine the relationship between the four independent variables and the dependent variable. In addition to tests for statistical significance, practical significance was evaluated with the multiple R2 , which reported the common variance between independent variables and dependent variable. The two variables of learner-content and learner-instructor interaction play a significant role in predicting online satisfaction. Minimally, the variable learner-technology can predict online satisfaction and is an important construct that must be considered when offering online courses. Results of this study provide help in establishing a valid and reliable …
Date:
May 2012
Creator:
Ahn, Byungmun
Object Type:
Thesis or Dissertation
System:
The UNT Digital Library
Low Leakage Asymmetric Stacked Sram Cell
Memory is an important part of any digital processing system. On-chip SRAM can be found in various levels of the memory hierarchy in a processor and occupies a considerable area of the chip. Leakage is one of the challenges which shrinking of technology has introduced and the leakage of SRAM constitutes a substantial part of the total leakage power of the chip due to its large area and the fact that many of the cells are idle without any access. In this thesis, we introduce asymmetric SRAM cells using stacked transistors which reduce the leakage up to 26% while increasing the delay of the cell by only 1.2% while reducing the read noise margin of the cell by only 15.7%. We also investigate an asymmetric cell configuration in which increases the delay by 33% while reduces the leakage up to 30% and reducing the read noise margin by only 1.2% compared to a regular SRAM cell.
Date:
May 2014
Creator:
Ahrabi, Nina
Object Type:
Thesis or Dissertation
System:
The UNT Digital Library
An Introduction to Contemporary Characteristics in Twentieth-Century Piano Music for the Late-Intermediate Student: A Pedagogical Analysis of the Bagatelles, Opus 5 by Alexander Tcherepnin
Alexander Tcherepnin (1899-1977) was a Russian-born American composer, his musical style represents the modern and diverse features of much twentieth-century piano music. The purpose of this research is to conduct a comprehensive pedagogical analysis of Alexander Tcherepnin's Bagatelles, Op. 5 with the goal of introducing contemporary characteristics in twentieth-century piano music for the late-intermediate student. Chapter 2 contains overall biographical information regarding Alexander Tcherepnin and a discussion of the general compositional style of his piano works. Chapter 3 analyzes the Bagatelles, Op. 5 from the perspective of musical challenges concerning the contemporary characteristics, including contemporary harmony: interval of seconds, non-tertian chords, special use of the seventh chords, and ninth chords; contemporary rhythm and meter: shifted accents, asymmetric meter, meter change, and ostinato; modal melodic resources and tonalities; and other special tonalities. Chapter 4 has suggestions on fingering, pedaling, articulation, tone, dynamics and phrasing, and practicing procedures for individual technical difficulties. Studying the Bagatelles, Op. 5 provides a transition for the student from learning standard repertoire of the eighteenth and the nineteenth century, to contemporary repertoire through the combination of Russian compositional traditions with twentieth century repertory.
Date:
May 2019
Creator:
Ai, Meilin
Object Type:
Thesis or Dissertation
System:
The UNT Digital Library
Space in Space: Privacy Needs for Long-Duration Spaceflight
Space exploration is a uniquely human activity. As humans continue to push the limits of exploring the unknown, they have sought knowledge supporting the sustenance of life in outer space. New technologies, advancements in medicine, and rethinking what it means to be a “community” will need to emerge to support life among the stars. Crews traveling beyond the Moon will rely on the development of new technologies to support the technological aspects of their missions as well as their quality of life while away from Earth. Likewise, through advancements in medicine, scientists will need to address remaining questions regarding the effects of long-duration spaceflight on the human body and crew performance. Space explorers must learn to utilize these new technologies and medical advancements while learning to adapt to their new environment in space and as a space community. It is important that researchers address these issues so that human survival beyond Earth is not only achievable but so that life among the stars is worth living and sustaining. This thesis addressed these issues in an attempt to extend the trajectory of space exploration to new horizons.
Date:
May 2014
Creator:
Aiken, Jo
Object Type:
Thesis or Dissertation
System:
The UNT Digital Library
Determination of the Optimal Number of Strata for Bias Reduction in Propensity Score Matching.
Previous research implementing stratification on the propensity score has generally relied on using five strata, based on prior theoretical groundwork and minimal empirical evidence as to the suitability of quintiles to adequately reduce bias in all cases and across all sample sizes. This study investigates bias reduction across varying number of strata and sample sizes via a large-scale simulation to determine the adequacy of quintiles for bias reduction under all conditions. Sample sizes ranged from 100 to 50,000 and strata from 3 to 20. Both the percentage of bias reduction and the standardized selection bias were examined. The results show that while the particular covariates in the simulation met certain criteria with five strata that greater bias reduction could be achieved by increasing the number of strata, especially with larger sample sizes. Simulation code written in R is included.
Date:
May 2010
Creator:
Akers, Allen
Object Type:
Thesis or Dissertation
System:
The UNT Digital Library
Sexual Identity and Social Anxiety in Emerging Adulthood
Elevated social anxiety (SA) is linked to issues with emotional distress, substance use, and social anxiety disorder (SAD). Notwithstanding concerns of how sexuality has been defined in the extant literature, emerging evidence suggests that the prevalence of SA and related challenges may be disproportionately present among sexual minorities, including lesbians, gay men, and bisexuals (LGBs). This trend may be especially relevant within the developmental context of emerging adulthood, an important period for development of sexual identity, and a time when individuals are already predisposed to heightened feelings of SA. The present study examined the relationship between sexual orientation (measured using sexual identity, sexual attraction, and past romantic and sexual behavior) and social anxiety (related to social interaction and social performance) among emerging adults. minority sexual identities [Welch's F(5,48.08) = 5.56, p = .002, ηp2 = .02.], same-sex attraction [Welch's F(4,108.06) = 11.27, p < .001, ηp2 = .04], and same-sex romantic [Welch's F(5,85.91) = 6.88, p < .001, ηp2 = .03] and sexual experiences[F(5,61.95) = 8.88, p < .001, ηp2 = .04], particularly among those who indicated attraction to multiple sexes. Findings support research that indicates that sexual minority adults experience higher levels of SA than majority (i.e., heterosexual, opposite-sex …
Date:
May 2017
Creator:
Akibar, Alvin
Object Type:
Thesis or Dissertation
System:
The UNT Digital Library