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Accent and Grouping Structures in the String Quartets of Béla Bartók (open access)

Accent and Grouping Structures in the String Quartets of Béla Bartók

The music of Béla Bartók is defined in part by its unique blend of rhythmic vitality and inventiveness, and his string quartets offer a glimpse into a consistency of technique evident throughout his compositional career. Bartók's rhythmic environments are primarily metrical, but many of his rhythmic configurations are placed in such a way as to potentially override established meter. It is necessary, therefore, to institute an analytical means by which the delineation and comparison of rhythmic structures both within and without the metrical context may be accomplished. An analytical method using Timepoint Accent Structures (TAS) allows for the comparison of rhythms resulting from patterns of accent produced by pitch onset, dynamic stress, articulation or any other accentual factors. Timepoint Grouping Structures (TGS) delineate the number of timepoints present in alternating groups/blocks in a texture, thereby allowing for the recognition of patterning created by these larger groups. By applying TAS and TGS analysis, relationships of rhythmic equivalency, rotation, retrograde, complementation, augmentation, diminution, subset, superset, exchange, compression and expansion are clearly confirmed in the string quartets. In addition, symmetrical structures and arithmetic progressions are discovered. In many ways, Bartók's rhythmic organization mimics his procedures of pitch structuring.
Date: May 2001
Creator: Bocanegra, Cheryl D.
System: The UNT Digital Library
Accounting for Human Resources: Implications for Theory and Practice. (open access)

Accounting for Human Resources: Implications for Theory and Practice.

Knowledge workers are an important resource for the typical modern business firm, yet financial reporting ignores such resources. Some researchers contend that the accounting profession has stressed reliability in order to make the accounting appear objective. Others concur, noting that accounting is an insecure profession and adopts strict rules when faced with uncertainty. Accountants have promulgated a strict rule to expense human resource costs, although many know that such resources have future benefits. Some researchers suggest that any discipline must modify its language in order to initiate change toward providing useful social ameliorations. If accounting theorists extend this idea to the accounting lexicon.s description of investments in human resources, investors and other accounting user groups might gain greater insight into how a firm fosters and nourishes human capital. I tested three hypotheses related to this issue by administering an experiment designed to assess financial analysts. perceptions about alternative financial statement treatments of human resources in an investment recommendation task. I predicted that (1) analysts' perceptions of the reliability (relevance) of the information they received would decrease (increase) as the treatment of human resources increasingly violated GAAP (became more current-oriented), (2) analysts exposed to alternative accounting treatments would report a lower …
Date: December 2001
Creator: Stovall, Olin Scott
System: The UNT Digital Library
Age-Dependent Effects Of Chronic GABAA  Receptor Blockade In Barrel Cortex (open access)

Age-Dependent Effects Of Chronic GABAA Receptor Blockade In Barrel Cortex

GABAA receptor binding is transiently increased in rat whisker barrels during the second postnatal week, at a time when neurons in the developing rat cortex are vulnerable to excitotoxic effects. To test whether these GABAA receptors might serve to protect neurons from excessive excitatory input, polymer implants containing the GABAA receptor antagonist bicuculline were placed over barrel cortex for a 4-day period in young (postnatal days 8 - 12) and adult rats. In the cortex of young, but not adult rats, the chronic blockade of GABAA receptors resulted in substantial tissue loss and neuron loss. The greater loss of neurons in young rats supports the hypothesis that a high density of GABAA receptors protects neurons from excessive excitatory input during a sensitive period in development.
Date: May 2001
Creator: Gargan, Lynn
System: The UNT Digital Library

Alexander Johnson's Ni' Concerto (1994) - Concerto no. 1 for Piano and Orchestra: a Discussion of Influences from Africa, Eastern and Western Europe

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In the new generation of artists emerging in South Africa, Alexander Johnson is considered the most prolific young composer of his day. In a recent review in the Pretoria News, Johnson has been praised by eminent critic Paul Boekkooi as a composer who has “an ear for the exotic and knows exactly how to bring it off....” He continued by noting that his music is “mentally engrossing, pleasurable to the senses and seems refreshingly free from dogmatic formulas." Johnson writes for musicians and the general public to equal satisfaction. His accessible compositions and catching use of melodic materials have made his writings very popular both in South Africa and abroad. During his residency in Belgrade in 1993-94, Johnson met Croatian pianist Dorian Leljak. Impressed with Johnson's compositional ideas and output, Leljak commissioned a work from Johnson for piano and orchestra. The result was the Niš Concerto, which Johnson completed in April 1994. The world premiere took place on June 23, 1994 with the Niš Philharmonic Orchestra conducted by Anatoli Nowiestski with Dorian Leljak as soloist. The Niš Concerto received its South African premiere in 1995 during a simultaneous celebration for “Europe Day” and the new democracy of the Republic of …
Date: August 2001
Creator: Malan, Petronel
System: The UNT Digital Library
An Analysis of Sales People's Perceptions of Performance Appraisal Criteria at a Telecommunications Corporation. (open access)

An Analysis of Sales People's Perceptions of Performance Appraisal Criteria at a Telecommunications Corporation.

The purpose of this study was to identify and analyze sales people's perceptions of performance appraisal criteria in a telecommunications corporation. The study was prompted by the perceived disillusionment of the sales people with the current performance appraisal criteria. The perceptions of 67 sales people were assessed using a questionnaire developed by the researcher. One-way analysis of variance procedures (ANOVA) were used to determine if there were statistically significant differences in premise and telemarketing sales people's perceptions of performance appraisal criteria. Findings indicated that there were no statistically significant difference in premise and telemarketing sales people's perceptions of the 38 performance appraisal criteria statements. Findings did not indicate a statistically significant difference in premise and telemarketing sales people's perceptions of the performance criteria statements, the attitude or satisfaction statements, and the peripheral issue statements. Based on this study, the sales people appear to have clear perceptions of the performance appraisal criteria.
Date: December 2001
Creator: Harris, Ellen L.
System: The UNT Digital Library
An Analysis of Teaching Periodicals for Aging Education Content (open access)

An Analysis of Teaching Periodicals for Aging Education Content

Ninety elementary public school teachers were surveyed to find out where they obtained their teaching ideas. Seven popular elementary-level teaching periodicals, dated 1989-1999, were analyzed for aging-related content, and compared with 27 of the National Academy for Teaching and Learning about Aging (NATLA) aspects of aging recommended for students' learning. Results indicate that public elementary teachers obtain their teaching ideas from various places: teaching institutes or workshops; other teachers; ideas or lessons they develop themselves; and teaching periodicals. A large percentage obtain lesson ideas from teaching periodicals that they browse or read. This finding may assist NATLA in making recommendations to particular editorial boards. Surprisingly, few teachers obtain their teaching ideas from state and local curricular mandates. When the periodical issues were analyzed, aging-related content was categorized in four ways: informational articles with selected teaching or learning activities; articles describing intergenerational programs or activities; book reviews with selected learning activities; and book review titles mentioning older adult characters. Category totals among the 7 periodicals were highest in book review titles mentioning older adult characters and book reviews with selected learning activities. The content was compared to NATLA's recommendations for students' learning. The findings were not significant. The aging aspect that …
Date: May 2001
Creator: Wimsatt, T. Joy
System: The UNT Digital Library
An Analysis of the Effect of Environmental and Systems Complexity on Information Systems Failures (open access)

An Analysis of the Effect of Environmental and Systems Complexity on Information Systems Failures

Companies have invested large amounts of money on information systems development. Unfortunately, not all information systems developments are successful. Software project failure is frequent and lamentable. Surveys and statistical analysis results underscore the severity and scope of software project failure. Limited research relates software structure to information systems failures. Systematic study of failure provides insights into the causes of IS failure. More importantly, it contributes to better monitoring and control of projects and enhancing the likelihood of the success of management information systems. The underlining theories and literature that contribute to the construction of theoretical framework come from general systems theory, complexity theory, and failure studies. One hundred COBOL programs from a single company are used in the analysis. The program log clearly documents the date, time, and the reasons for changes to the programs. In this study the relationships among the variables of business requirements change, software complexity, program size and the error rate in each phase of software development life cycle are tested. Interpretations of the hypotheses testing are provided as well. The data shows that analysis error and design error occur more often than programming error. Measurement criteria need to be developed at each stage of the …
Date: August 2001
Creator: Zhang, Xiaoni
System: The UNT Digital Library

Analysis of the Impact of CACREP Accreditation of Counselor Education Programs on Student Knowledge Outcomes

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The principal investigator (PI) for this study analyzed mean scores on the National Counselor Examination (NCE) of students from CACREP accredited and non- CACREP accredited programs. Data was provided by the National Board of Certified Counselors, Inc., for a total of ten examination administrations across six years. The fourteen variables examined in the study consisted of the eight common-core knowledge domains identified in CACREP standards, the five counselor work behavior areas identified by NBCC via periodic job analysis of counseling practice, and one overall or total score on the NCE. NCE mean scores of students from CACREP accredited programs were higher than NCE mean scores of students from non-CACREP accredited programs on all variables across all ten NCE administrations. Data seem to indicate that students from CACREP accredited programs perform significantly better on the NCE than students from non-CACREP accredited programs, in all fourteen variables. Sample size was large, totaling 9707, so the PI calculated effect sizes using Cohen's d for each variable to aid interpretation of statistical significance. Five variables had large effect sizes of .70 or higher. The higher effect size statistics were associated with the counselor work behavior areas, with the highest effect size (.85) associated with …
Date: May 2001
Creator: Scott, Susan W.
System: The UNT Digital Library

Anne Brontë's New Women: Agnes Grey and The Tenant of Wildfell Hall as Precursors of New Woman Fiction

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Anne Brontë's Agnes Grey and The Tenant of Wildfell Hall were published more than forty years before the appearance of the feminist type that the Victorians called the “New Woman;” yet, both novels contain characteristics of New Woman fiction. By considering how Brontë's novels foreshadow New Woman fiction, the reader of these novels can re-enact the “gentlest” Brontë as an influential feminist whose ideology informed the construction of the radical New Woman. Brontë, like the New Woman writers, incorporated autobiographical dilemmas into her fiction. By using her own experiences as a governess, Brontë constructs Agnes Grey's incongruent social status and a morally corrupt gentry and aristocracy through her depiction of not only Agnes's second employers, the Murrays, but also the morally debauched world that Helen enters upon her marriage to Arthur Huntingdon in The Tenant of Wildfell Hall. Moreover, Brontë incorporates her observations of Branwell's alcoholism and her own religious beliefs into The Tenant of Wildfell Hall. Although Brontë's novels contain autobiographical material, her heroines are fictional constructions that she uses to engage her readers with the woman question. Brontë accomplishes this engagement through her heroines' narrative re-enactments of fictional autobiographical dilemmas. Helen's diary and Agnes's diary-based narrative produce the …
Date: August 2001
Creator: Phillips, Jennifer K.
System: The UNT Digital Library
The Application of Hackman and Oldham's Job Characteristic Model to Perceptions Community Music School Faculty Have Towards Their Job (open access)

The Application of Hackman and Oldham's Job Characteristic Model to Perceptions Community Music School Faculty Have Towards Their Job

Hackman and Oldham's Job Characteristic Model was applied to study of perceptions community music school faculty hold towards their job. The research questions addressed core job characteristics of skill variety, task identity, task significance, autonomy, and feedback, critical psychological states (experienced meaningfulness, experienced responsibility, and knowledge of results); personal and work outcomes of satisfaction and motivation; need for professional growth. The results were compared to the national norms for nine different job families provided by Oldham, Hackman, and Stepina. Thirty-three schools, all members of the National Guild of Community Schools of the Arts, located in every geographical region of the United States, yielded 437 faculty responses (64% return rate). Of the core job characteristics, dealing with others and autonomy received the highest ratings; feedback and task significance received the lowest ratings. Of the psychological states, experienced responsibility yielded the highest rating and experienced meaningfulness yielded the lowest ratings. Of the personal/work outcomes, personal development and colleague relations received the highest ratings; pay satisfaction and overall general satisfaction received the lowest ratings. A comparison to the professional job family norms, using a one-sample ttest, found significant differences in 16 out of the 18 variables measured by the Job Characteristic Model. Strong …
Date: August 2001
Creator: Lawrence, Robert M.
System: The UNT Digital Library
The Assessment of Cognitive Development and Writing Aptitude Within Learning Communities (open access)

The Assessment of Cognitive Development and Writing Aptitude Within Learning Communities

Learning communities have emerged as an efficient and effective paradigm for improving undergraduate education, especially for entering freshmen. The academy has become increasingly interested in learning outcomes and student retention, especially as they are related to the assessment of various approaches to educating the whole student. Learning community pedagogy has developed through rigorous research. However, little is known about the impact of this pedagogy upon college students' cognitive development and writing aptitude. Cognitive development theory has been most significantly influenced by the work of William G. Perry, Jr. Though no theory exists which would address the stages of writing development in university students, many composition theorists suggest a correlation between cognitive development and writing aptitude. This study measured cognitive development and writing aptitude in learning community students and non-learning community students, matching them for SAT scores, high school grade point averages, gender, and ethnicity. The research questions of interest were: 1) How does participation in a learning community affect students' cognitive development; and 2) How does participation in a learning community affect students' writing aptitude? The participants were pre- and post-assessed for cognitive development, using the Measure of Intellectual Development (MID). Additionally, participants were preand post-assessed for writing aptitude, using …
Date: August 2001
Creator: Barnard, Miriam K.
System: The UNT Digital Library
Attitudes of American and Korean Early Childhood Educators Regarding Programs for Gifted/Talented Young Children. (open access)

Attitudes of American and Korean Early Childhood Educators Regarding Programs for Gifted/Talented Young Children.

The purpose of this research was to study the attitudes of Korean and American early childhood educators concerning gifted children and programs aimed specifically at meeting their needs. The study examined general attitudes towards giftedness and gifted education programs and factors that might affect those attitudes. The study also examined desirable environments for young gifted children. Twenty-item questionnaires were developed and logically divided into six sections (identification, teacher environment, classroom environment, parent environment, educational rights, and program). A systematic process of development, analysis, and refinement of the questionnaire was done. The questionnaires were given randomly to American educators attending the 1996 National Association for the Education of Young Children (NAEYC) conference. A random Korean sample included early childhood educators listed in the Korean Association for Early Childhood Education Directory (1995-1996) and the Korean Association for Child Care Directory (1995-1996). All subjects were members of one of three groups: (a) teacher educators, (b) teachers, and (c) administrators/directors. The surveys found agreement between Korean and American early childhood educators on the importance of knowing the strengths of individual gifted children, the need to stimulate higher order thinking skills, the rights of gifted children to an appropriate education, a perception of more work …
Date: December 2001
Creator: Song, Kyu-Woon
System: The UNT Digital Library

Burnout Among Student Affairs Professionals at Metropolitan Universities

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The purpose of this study was to determine the level of burnout among student affairs professionals at the 52 U.S. member institutions of the Coalition of Urban and Metropolitan Universities. Packets containing the Maslach Burnout Inventory (MBI), the Moos Work Environment Scale (WES), and a demographic survey were mailed to 371 senior student affairs administrators at the member institutions, with a completed response rate of 58.22%. The senior student affairs administrators surveyed included the chief student affairs officers and the professional staff who reported to them. The research design employed t-tests, analyses of variance, and Pearson's Product Moment correlations. The scores obtained from the MBI and WES subscales were compared overall and along 9 independent variablestitle of position, size of institution, appointment, salary, years in current position, years in profession, age, gender, and highest degree attained. Average levels of burnout were found on each of the MBI subscores. Contrary to earlier studies, women did not suffer from statistically significant higher levels of burnout than men, and burnout levels decreased with age and years in the profession for both sexes. Lower scores on the MBI depersonalization subscale were found in employees in mid-career and in professionals from smaller schools. Emotional exhaustion …
Date: August 2001
Creator: Murphy, Lynda
System: The UNT Digital Library
Career Paths of Female Chief Academic Officers in the Council for Christian Colleges and Universities (open access)

Career Paths of Female Chief Academic Officers in the Council for Christian Colleges and Universities

This study examined the career paths of women administrators serving as chief academic officers in Christian colleges and universities which belong to the Council for Christian Colleges and Universities (CCCU). The CCCU is a professional association of evangelical Christian institutions dedicated to integrating faith and learning. The exploration included each administrator's demographic information; her early, adolescent, college, and graduate school experiences; early vocational experiences; the effect of marriage and motherhood on her career; critical factors she identified as important in achieving her current position; and the importance of spiritual convictions or Christian faith in career decision making. Sixteen of the eighteen identified women holding the rank of chief academic officer agreed to participate in the study. The typical woman administrator was 50, married, and the mother of one or more children. She most likely had received her education in the humanities, with the terminal degree of choice being a Ph.D. She had served at her current institution for more than five years, but in her current administrative position for less than five. As an adolescent she excelled in the humanities, less so in math and science, and was involved in many extracurricular activities, including music endeavors, leadership, and her local …
Date: May 2001
Creator: Moreton, April L.
System: The UNT Digital Library
The Characteristics of Teacher-Directed Modeling Evidenced in the Practices of Three Experienced High School Choral Directors. (open access)

The Characteristics of Teacher-Directed Modeling Evidenced in the Practices of Three Experienced High School Choral Directors.

The purpose of this study was to analyze the characteristics of teacher directed modeling evidenced in the practices of three experienced high school choral directors. Research questions were: 1. What modeling activities were exhibited in each teacher's rehearsals? 2. When viewing a 45-minute composite tape of each teacher's instructional activities representative of all rehearsals, what instructional behaviors did each choral director recognize and identify as modeling? 3. What instructional episodes on the composite tape not identified by the teachers contained elements of modeling? 4. What other episodes from the remainder of each choral director's rehearsal practice contributed to an understanding of modeling? Videotapes of three high school choral directors were recorded over the course of one semester. Excerpts from rehearsals were combined to form a 45-minute composite tape of each choral director. A text transcription was made of the composite tape. Participant directors viewed their tape and identified instructional episodes that they recognized as examples of modeling. Identifications were analyzed, and descriptive categories of modeling behaviors were established. Modeling was found to be a teacher generated or delegated act of demonstration. Demonstrations were musical or non-musical and belonging to either of three distinct categories: audible, visible, or process modeling. Subdivisions …
Date: December 2001
Creator: Grimland, Fredna H.
System: The UNT Digital Library
Choice for All? Charter Schools and Students with Disabilities (open access)

Choice for All? Charter Schools and Students with Disabilities

In order to assess the extent and quality of special education services in charter schools in north Texas, the researcher examined data submitted to Texa Public Education Information Management System (PEIMS), and conducted qualitative interviews with selected charter school administrators. Five cornerstones of the Individuals with Disabilities Education Act (IDEA): zero reject, individualized education program (IEP), appropriate assessment, free appropriate public education (FAPE), and least restrictive environment (LRE), were utilized in the assessment of quality. Levels of expertise in federal disability law and fiscal barriers were explored, as well.
Date: August 2001
Creator: Estes, Mary Bailey
System: The UNT Digital Library
Christian Higher Education at Dallas Theological Seminary: An Assessment of Doctor of Ministry Programs (open access)

Christian Higher Education at Dallas Theological Seminary: An Assessment of Doctor of Ministry Programs

This study involved non-experimental research to identify alumni perceptions of the strengths and weaknesses of the Doctor of Ministry degree program at Dallas Theological Seminary. An international survey was conducted to collect data from 165 Doctor of Ministry degree holders from Dallas Theological Seminary; 131 usable questionnaires were returned. A response rate of 79.4 percent was achieved. The intent of the study was to ascertain (a) the extent to which D.Min. alumni perceive that the objectives and goals of Doctor of Ministry programs at Dallas Theological Seminary are being met, (b) alumni-perceived strengths of Doctor of Ministry programs at Dallas Theological Seminary, (c) alumni-perceived weaknesses of Doctor of Ministry programs at Dallas Theological Seminary, (d) compare the findings of this case study assessment with a 1987 national study of Doctor of Ministry programs, and (e) make recommendations for the improvement of D. Min programs at Dallas Theological Seminary. The pattern that emerged from the data indicates that the D.Min. alumni believe objectives and goals of the Doctor of Ministry program at Dallas Theological Seminary are being met. In the opinion of the alumni, Doctor of Ministry programs at Dallas Theological Seminary has its strengths. The overall opinion of the D.Min. …
Date: August 2001
Creator: Bhatia, Sukhwant Singh
System: The UNT Digital Library
A Collapsing Result Using the Axiom of Determinancy and the Theory of Possible Cofinalities (open access)

A Collapsing Result Using the Axiom of Determinancy and the Theory of Possible Cofinalities

Assuming the axiom of determinacy, we give a new proof of the strong partition relation on ω1. Further, we present a streamlined proof that J<λ+(a) (the ideal of sets which force cof Π α < λ) is generated from J<λ+(a) by adding a singleton. Combining these results with a polarized partition relation on ω1
Date: May 2001
Creator: May, Russell J.
System: The UNT Digital Library
Combat Reconsidered: A Statistical Analysis of Small-Unit Actions During the American Civil War (open access)

Combat Reconsidered: A Statistical Analysis of Small-Unit Actions During the American Civil War

Historians often emphasize the physical features of battleterrain, weaponry, troop formations, earthworks, etc.in assessments of Civil War combat. Most scholars agree that these external combat conditions strongly influenced battle performance. Other historians accentuate the ways in which the mental stresses of soldiering affected combat performance. These scholars tend to agree that fighting effectiveness was influenced by such non-physical combat conditions as unit cohesion, leadership, morale, and emotional stress. Few authors argue that combat's mental influences were more significant in determining success or failure than the physical features of the battlefield. Statistical analysis of the 465 tactical engagements fought by twenty-seven Federal regiments in the First Division of the Army of the Potomac's Second Corps throughout the American Civil War suggests that the mental aspects of battle affected fighting efficiency at least as muchand probably more thancombat's physical characteristics. In other words, the soldiers' attitudes, opinions, and emotions had a somewhat stronger impact on combat performance than their actions, positions, and weaponry.
Date: December 2001
Creator: Barloon, Mark C.
System: The UNT Digital Library
A Comparative Analysis of the Effectiveness of Three Different GED Preparation Programs (open access)

A Comparative Analysis of the Effectiveness of Three Different GED Preparation Programs

The purpose of this study was to identify effective instructional programs for GED tests preparation for students in a large suburban school district. Three different nonrandom, unequal naturally occurring instructional groups at three different locations were examined. One group participated in a traditional instruction program, a second group in a test/retest program, and a third group in a computer-assisted program. The demographics of the district population, the GED population, and the individual study groups were catalogued and analyzed. The demographics of the GED population were similar to the district population but different from the GED passers. Student characteristics did affect GED success. Both quantitative and qualitative data were gathered. Random students in each of the three groups were interviewed about their experiences in GED preparation using a questionnaire. Quantitative data were analyzed using frequencies, means, correlations, and a multiple regression analysis. Since the GED credential is an alternative to the high school diploma, its use as a dropout alternative is important to every school district. The study found that instructional methods had little impact on students' success in receiving the GED credential. The overall success rate of students was low in each group. The student's reading achievement score, GPA, and …
Date: May 2001
Creator: Gardner, Marlene K.
System: The UNT Digital Library
A Comparative Analysis of Traditional Versus Block and Accelerated Block Scheduled High Schools Over an Eight-Year Period in a Large Urban School District (open access)

A Comparative Analysis of Traditional Versus Block and Accelerated Block Scheduled High Schools Over an Eight-Year Period in a Large Urban School District

This study compared traditional, A/B and accelerated block scheduling and its effects on student achievement and attendance by comparing the differences in student outcomes observed before and after the adoption of block/accelerated block schedules. The independent variable was the use of time in a block-scheduling model. The dependent variables were student outcomes measured by nine indicators based on the Academic Excellence Indicator System in Texas: student attendance, graduation rate, dropout rate, percentage of students taking advanced courses, percentage of students passing all Exit-level Texas Assessment of Academic Skills tests, percentage of students taking College Admissions Tests, mean SAT total score of those students who took the SAT, mean ACT total score of those students who took the ACT, and percentage of students who are at or above criterion on the SAT or ACT of those students taking the SAT or ACT. Data from archival files from the Texas Education Agency's Academic Excellence Indicator System for each respective year of the eight-year longitudinal study was collected. Scheduling models (traditional, alternating block and accelerated block) were investigated. The sample was drawn from the student population of a large urban school district in north central Texas, a district serving approximately 77,000 students. The …
Date: August 2001
Creator: McCumber, Patricia Morrison
System: The UNT Digital Library

Comparative Morphology of Sensilla Styloconica on the Proboscis of North American Nymphalidae and Other Selected Taxa: Systematic and Ecological Considerations.

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Sensilla styloconica on the proboscis of 107 species of North American and tropical butterflies were comparatively studied using the scanning electron microscope. Focus was on 76 species of North American Nymphalidae representing 45 genera and 11 subfamilies. Nomenclature for generalized and specific types of nymphalid sensilla is proposed. Written descriptions and micrographs are presented for each species studied. Morphological features were generally consistent for all or most species within genera and sometimes within subfamilies, with specified exceptions. Statistical analysis revealed significant differences for six of eight variables tested between two distinct feeding guilds of North American Nymphalidae. Average number, density, extent of proboscis coverage with sensilla, their total length, and shoulder spine length were all significantly greater in the non-nectar feeding guild than in nectar feeders, and may indicate adaptation for greater efficiency in feeding on flat surfaces. The greater frequency of apical shoulder spines in non-nectar feeders may represent adaptation for protection of sensory pegs from mechanical abrasion during feeding, or for anchoring the flexible proboscis tip to the surface. Correlation analysis revealed 9 out of 28 positive correlations in nectar feeders and 5 out of 28 in non-nectar feeders. Results of preliminary cladistic analysis were not considered to …
Date: December 2001
Creator: Petr, Daniel
System: The UNT Digital Library

A Comparison of Five Robust Regression Methods with Ordinary Least Squares: Relative Efficiency, Bias and Test of the Null Hypothesis

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A Monte Carlo simulation was used to generate data for a comparison of five robust regression estimation methods with ordinary least squares (OLS) under 36 different outlier data configurations. Two of the robust estimators, Least Absolute Value (LAV) estimation and MM estimation, are commercially available. Three authormodified variations on MM were also included (MM1, MM2, and MM3). Design parameters that were varied include sample size (n=60 and n=180), number of independent predictor variables (2, 3 and 6), outlier density (0%, 5% and 15%) and outlier location (2x,2y s, 8x8y s, 4x,8y s and 8x,4y s). Criteria on which the regression methods were measured are relative efficiency, bias and a test of the null hypothesis. Results indicated that MM2 was the best performing robust estimator on relative efficiency. The best performing estimator on bias was MM1. The best performing regression method on the test of the null hypothesis was MM2. Overall, the MM-type robust regression methods outperformed OLS and LAV on relative efficiency, bias, and the test of the null hypothesis.
Date: August 2001
Creator: Anderson, Cynthia, 1962-
System: The UNT Digital Library
A Comparison of Quantitative Skills in Texas Year-round Schools with Texas Traditional Calendar Schools (open access)

A Comparison of Quantitative Skills in Texas Year-round Schools with Texas Traditional Calendar Schools

This study analyzed the academic impact of year-round calendar schools as compared with the academic achievement of traditional calendar schools. The population studied was the 1998 public elementary schools in Texas. The academic impact was based upon the 1998 Texas Assessment of Academic Skills (TAAS) test administrated by the Texas Education Agency. The two groups of schools studied were Texas elementary schools that were on a year-round calendar schedule, and the Texas elementary schools on a traditional calendar schedule. Multiple regression statistics were used, in addition to means, and differences between the means of variables. Year-round schools (YRE), when compared to the means of traditional schools, have means lower in math scores (6.16 percent) than traditional schools. Year-round schools have fewer African Americans students (2.78%), White students (21.06%), and special education students (.25%). Year-round schools are higher in population size (72.72students), Economic Disadvantaged students (15.87%), Hispanic students (23.46%), and Mobility (3.23%).
Date: May 2001
Creator: Cole, Homer W.
System: The UNT Digital Library