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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
61

The Effect of Procedural Justice During Police-Citizen Encounters: A Factorial Vignette-Based Study

January 2016 (has links)
abstract: ABSTRACT Many studies testing the effects of procedural justice judgments rely on cross-sectional data. The shortcomings of such a strategy are clear and alternative methodologies are needed. Using a factorial vignette design, this study tests a variety of hypotheses derived from the process-based model of regulation, most of which involve the posited outcomes of procedural justice judgments during police-citizen encounters. This technique allows the researcher to manipulate police process during citizen encounters via hypothetical scenarios. Experimental stimuli are used as independent variables in the regression models. The results show that participants who were administered vignettes characterized by procedural injustice had lower levels of encounter satisfaction, decision acceptance, immediate compliance and greater expectations that police handle similar situations in the future differently relative to individuals who did not receive the negative stimulus. These effects are statistically significant across encounters involving traffic stops and noise complaints. As anticipated, the effect of procedural injustice often proved more salient regardless of whether participants were administered vignettes where they received a citation. Given the utility of the vignette design, future researchers are encouraged to apply the design to additional causal questions derived from the process-based model. / Dissertation/Thesis / Masters Thesis Criminology and Criminal Justice 2016
62

Measures of simplicity and factorial fit: An approach for the evaluation of factorially derived scales / Medidas de simplicidad y de ajuste factorial: un enfoque para la evaluación de escalas construidas factorialmente

Fleming, James S., Merino Soto, César 25 September 2017 (has links)
A very simple structure is sought when using factor analysis to develop measurement scales. The present article is about the SIMLOAD program; it computes measures of factor simplicity for rows and columns of loading matrices (usually the factor pattern) as well assome overall measures. These include Kaiser’s (1974) index of factor simplicity for variables (rows), Fleming’s scale fit index for factors (columns), Bentler’s (1977) scale-free matrix measure, and hyperplane counts. Routine use of these measures is recommended for multifactor scale development. The measures may also be useful in more general factorapplications, and in confirmatory as well as  exploratory analysis. SIMLOAD additionally computes factor scale intercorrelations, scale alpha coefficients, including alpha when item removed, and sorted loadings for ease of interpretation. / Una estructura simple es sólida cuando se utiliza el análisis factorial para desarrollar instrumentos de medición. El presente artículo se basa en el programa SIMLOAD, que produce índices que miden la simplicidad factorial para las filas y columnas de una matriz de cargas factoriales (generalmente, el patrón de factores), tanto como índices globales de ajuste. Estos incluyen para las filas el índice de simplicidad factorial de Kaiser (1974); para las columnas, el índice de ajuste a la escala de Fleming; la medida matriz libre de escalas de Bentler (1977); y, el conteo de hiperplanos. Estas medidas se recomiendan para la construcción de escalas multifactoriales. Estos índices también pueden ser útiles para aplicaciones factoriales más generales, en el análisis exploratorio o confirmatorio. El programa SIMLOAD también calcula intercorrelaciones entre las escalas, coeficientes alfa de Cronbach, el efecto de la eliminación de un ítem sobre el alfa y el  ordenamiento de las cargas factoriales de los ítems para facilitar la interpretación de la matriz resultante.
63

Validez y confiabilidad de escala de afecto positivo y negativo (SPANAS) en estudiantes universitarios peruanos

Gargurevich, Rafael, Matos, Lennia 13 August 2014 (has links)
Se ha estudiado la validez de constructo y la confiabilidad de la escala SPANAS en dos muestras de estudiantes universitarios de Lima. Mediante diversos análisis factoriales confirmatorios (AFC) se evaluó el ajuste de tres modelos competidores (un solo factor, dos factores correlacionados y dos factores ortogonales). Este procedimiento se replicó en las dos muestras de estudiantes universitarios. Luego de haber realizado los análisis de validez y confiabilidad, se encontró que el modelo de dos factores correlacionados era el que mejor representó a la escala en ambas muestras. Además, las escalas de afecto positivo y negativo demostraron ser confiables. De esta manera se tiene evidencia de la presencia de dos factores que representan al afecto positivo y negativo. / It was studied the construct validity and the reliability of the SPANAS scale in two samples of university students from Lima. Through many confirmatory factorial analyses (AFC) it was evaluated the adjustment of three competing models (one factor, two correlated factors and two orthogonal factors). This procedure was replicated in the two samples of universitary students. After the validity and reliability analysis were done, it was found that the two correlated factors model was better to represent the scale in both samples. Furthermore, the Positive and Negative Affect Scale proved to be reliable. In this way we have evidence of the presence of two factors which represent the positive and negative affection.
64

Construction of uniform designs and usefulness of uniformity in fractional factorial designs

Qin, Hong 01 January 2002 (has links)
No description available.
65

Transcriptional Profiling of Chromera velia Under Diverse Environmental Conditions

Tayyrov, Annageldi 05 1900 (has links)
Since its description in 2008, Chromera velia has drawn profound interest as the closest free-­-living photosynthetic relative of apicomplexan parasites that are significant pathogens, causing enormous health and economic problems. There-­- fore, this newly described species holds a great potential to understand evolu-­- tionary basis of how photosynthetic algae evolved into the fully pathogenic Apicomplexa and how their common ancestors may have lived before they evolved into obligate parasites. Hence, the aim of this work is to understand how C. velia function and respond to different environmental conditions. This study aims to reveal how C. velia is able to respond to environmental perturbations that are applied individually and simultaneously since, studying stress factors in separation fails to elucidate complex responses to multi stress factors and un-­- derstanding the systemic regulation of involved genes. To extract biologically significant information and to identify genes involved in various physiological processes under variety of environmental conditions (i.e. a combination of vary-­- ing temperatures, iron availability, and salinity in the growth medium) we pre-­- pared strand specific RNA-­-seq libraries for 83 samples in diverse environmental conditions. Here, we report the set of significantly differentially expressed genes as a re-­- sponse to the each condition and their combinations. Several interesting up-­- regulated and down-­-regulated genes were found and their functions and in-­- volved pathways were studied. We showed that the profound regulation of HSP20 proteins is significant under stress conditions and hypothesized that the-­- se proteins might be involved in their movements.
66

A Factorial Ecology of Dallas County

Pol, Louis 08 1900 (has links)
The "Factorial Ecology of Dallas County" deals with the differentiation of census tracts based on combinations of census tract variables for Dallas County. The study examines this differentiation, using five factors which are analyzed in relation to concentric zone and sector theory. All of the analyses are based upon data which are available by census tract from the 1970 national census.
67

Systems Factorial Technology extended to bilateral visual fields and model predictions testing

Fan, Gaojie, Fan 07 January 2020 (has links)
No description available.
68

The Impact of an Academic Integrity Module and Turnitin on Similarity Index Scores of Undergraduate Student Papers

Ballard, Iva B 11 May 2013 (has links)
The researcher of this quasi-experimental 2 x 2 factorial design study investigated the impact of an academic integrity module and Turnitin on undergraduate student similarity index scores. Similarity index scores were used to measure suggested plagiarism rates of student papers. The purposive sample was made up of 96 undergraduate education students enrolled in four sections of the same course in a Southeastern university. One main factor was submitting assignments through Turnitin, with two levels: yes or no. The second factor was completing the academic integrity module, with two levels: yes or no. The four intact groups were randomly assigned to the main factors. Although the findings from this study indicated that neither main factor nor their interaction were statistically significant at the .05 alpha level, the mean similarity index score of participants who submitted their paper through Turnitin was lower than the mean similarity index score of participants who did not submit their papers through Turnitin. Similarly, the mean similarity index score of participants who completed the academic integrity module was lower than the mean similarity index score of participants who did not complete the academic integrity module. Although not at the statistically significant level, the plagiarism rate as measured by the mean similarity index score of the group of participants who completed the academic integrity module and submitted papers through Turnitin was the lowest followed by the group of participants that completed the academic integrity module but did not submit papers through Turnitin, then the group of participants that did not complete the academic integrity module and did not submit papers through Turnitin. The group of participants who did not complete the academic integrity module but submitted papers through Turnitin had the highest mean similar index score suggesting a higher plagiarism rate as compared to the other groups. Finally, the researcher acknowledged the limitations of this study and made recommendations for future consideration. Other variables such as gender, demographics, major, and credit hours completed could be investigated. Replication of the study is recommended. Also, a qualitative approach could enhance future studies.
69

Investigating the Impact of Electronic Prescribing System User Interface Design on Prescribing Accuracy

Wiercioch, Wojtek January 2014 (has links)
Background: Electronic prescribing systems are designed to aid in the complex process of prescribing by providing patient information and decision support at the point of care. Successful implementation and effectiveness depend on a variety of factors, including usability and user interface design, which influence how the information and decision support are relayed to users. Poorly designed systems have been found to be associated with medication errors. Methods: We conducted a factorial design study to investigate the impact of screen density, highlighting, and placement of information, on the accuracy of prescribing when using an e-prescribing system. Study sessions were held during clinical pharmacology educational rounds, where residents and medical students answered simulated prescribing scenarios presented on various e-prescribing system interface configurations. Assignment of prescribing scenarios to interface configurations and presentation order were randomized between study sessions. Participants were also asked about their preferences for specific user interface configurations. Results: A total of 66 participants completed 844 prescribing cases, with 583 (69%) cases answered correctly. The presence of highlighting was associated with correct prescribing decisions (p-value = 0.001), with 181 out of 250 (72.4%) prescribing scenarios answered correctly on interfaces with highlighting of key clinical information, as opposed to 156 out of 242 (64.5%) on interface configurations without. Low screen density and central placement of information were not found to be statistically significant predictors of prescribing accuracy. The presence of highlighting was the only factor that the majority of participants (80.3%) preferred, but no effect was found when comparing prescribing accuracy on preferred versus non-preferred interface configurations. Conclusions: The factorial design methodology developed is a novel approach for efficient and objective evaluation of multiple user interface design factors in one study. Evidence-based design and usability principles are needed to enhance the design and appropriate use of e-prescribing systems as usability problems continue to be one of the primary reasons for dissatisfaction and poor levels of adoption. / Thesis / Master of Science (MSc)
70

Simplex Optimization of Protein Crystallization Conditions

Prater, Bradley D., Tuller, Steven C., Wilson, Lori J. 15 January 1999 (has links)
Simplex algorithms have been used to optimize for size, number and morphology of lysozyme and apoferritin crystals. This approach requires fewer experiments than the single-factor-at-a-time method or factorial designs and will be useful in conserving materials on the International Space Station. The simplex method has the possible advantage that it conserves on materials by reducing the number of experiments required to optimize a crystallization system. The process is iterative and exploratory and should allow optimum microgravity conditions to be determined which might very well be different from the optimum conditions on Earth. Because the simplex method uses simple mathematical operations to calculate the next set of crystallization conditions it will be easier for crystal growers to implement than factorial designs. Factorial experiments are based on varying all factors simultaneously at a limited number of factor levels. This results in a model that is used to determine the influence of each factor and their interactions. Factorial design experiments are especially useful at the beginning of an experimental study and as a screening tool to investigate a large number of factors. The simplex method is an optimization method which is model-independent and requires no fitting of models to data. Also, when applied to protein crystal growth the simplex method does not rely on an absolute quality score. Instead, with each iteration a comparison is made to the last experiment and the results are assigned as being "better or worse". In this study, commercially obtained apoferritin was purified from 65% monomeric apoferritin to 92% monomeric apoferritin by size exclusion chromatography. Simplex optimization found the best apoferritin crystals were obtained at 15 mg/ml apoferritin, 2.0% CdSO4, 25°C using the hanging drop vapor diffusion method of crystallization and at 24 mg/ml apoferritin, 1.5% CdSO4, 25°C using the containerless crystallization method. For lysozyme, the simplex method found the best crystals at 19 mg/ml lysozyme, 7.0% (w/v) NaCl, pH 4.0, 25°C using the hanging drop vapor diffusion method of crystallization. For both proteins, the optimum conditions were found with less than ten experiments using very little protein. Finally, we report that the factors to be considered in the successful application of this method to crystallization are the number of variables to be studied, the initial conditions, step size and analysis of crystal quality.

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