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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.
181

Effects of Process-Oriented and Product-Oriented Worked Examples and Prior Knowledge on Learner Problem Solving and Attitude: A Study in the Domain of Microeconomics

Unknown Date (has links)
The purpose of this study was to investigate the effectiveness of process-oriented and product-oriented worked example strategies and the mediating effect of prior knowledge (high versus low) on problem solving and learner attitude in the domain of microeconomics. In addition, the effect of these variables on learning efficiency as well as the influence of learner attitude on mental effort was explored as part of a secondary analysis. Four-hundred fifteen undergraduate students enrolled in an introductory microeconomics course participated in the study. Participants were randomly assigned to one of three instructional strategies (process-oriented, product-oriented, or conventional problem solving) developed for this study. In addition, participants' were classified during the analysis phase as either low prior knowledge or high prior knowledge groups based on scores from a prior knowledge assessment. In the process-oriented strategy condition, participants were exposed to a fully worked out example that presented both procedural "how" and strategic (principle-based) "why" information underlying the solution. Participants in the product-oriented strategy condition were presented a worked out example with procedural information showing the steps necessary to solve a problem. In both worked example strategy conditions, participants completed a series of four process-oriented worked examples and three practice problems. Participants assigned to the conventional problem solving condition were asked to complete seven practice-problems. Regardless of the instructional condition, all participants received immediate feedback (i.e., correct answer) after the completion of a practice problem. The study included two instructional components: (1) a common lecture, and (2) completion of a print-based instructional activity. The twenty-minute lecture provided a conceptual overview of the impact of taxes on market activity. Two days later participants were assigned to one of the three instructional conditions and given fifty-minutes to complete the instructional activity. A performance assessment was administered four-days later to measure learning and transfer. Results suggested that instructional strategy had a minimal affect on participant learning and transfer performance, mental effort, and attitude toward the instruction. However, mean scores on the achievement test assessing student learning were found to be slightly higher for participants in either one of the worked example instructional strategies when compared to conventional problem solving. For mental effort, the findings indicated that participants, regardless of instructional strategy, invested a low amount of mental effort during the instructional tasks. Similarly, participants reported a relatively high (i.e., positive) attitude toward the instruction. In a post hoc analysis, participants in both the product-oriented worked example and the conventional problem solving groups that self-reported a higher level of confidence toward the instruction also invested a higher degree of mental effort during the instructional task. The study did support the mediating effect of prior knowledge on each dependent measure. The results of the present study have implications for the design of example-based instruction and for further research exploration of instructional task sequencing. Based on the findings of the present study, it is recommended that instructional designers consider participants' level of knowledge when designing learning strategies to teach complex problem solving skills. Furthermore, developing instructional methods or systems that adapt to a learner's cognitive and motivational differences has implications for the measurement of mental efficiency and the design of instructional and feedback protocols. Consequently, the implications for the design and utilization of process-oriented worked examples as a component of a sequenced instructional strategy are discussed further. / A Dissertation submitted to the Department of Educational Psychology and Learning Systems in partial fulfillment of the requirements for the degree of Doctor of Philosophy. / Fall Semester, 2009. / September 11, 2009. / Prior Knowledge, Learner Attitude, Cognitive Load Theory, Problem Solving, Worked Examples / Includes bibliographical references. / A. Aubteen Darabi, Professor Directing Dissertation; Gerald R. Ferris, University Representative; Linda B. Schrader, Committee Member; Robert A. Reiser, Committee Member.
182

A Comparison of Methods for Detecting Differential Distractor Functioning

Unknown Date (has links)
This study examined the effectiveness of the odds-ratio method (Penfield, 2008) and the multinomial logistic regression method (Kato, Moen, & Thurlow, 2009) for measuring differential distractor functioning (DDF) effects in comparison to the standardized distractor analysis approach (Schmitt & Bleistein, 1987). Students classified as participating in free and reduced-price lunch programs served as the focal group and students not participating in these programs served as the reference group. The comparisons were conducted in such a way as to provide insight into two research questions: 1) whether the magnitude and pattern of the DDF effect is constant across all methods, and 2) whether the pattern of DDF effects support differential item functioning (DIF) findings. Measures of effect size are reported. In addition, the relationship between item characteristics and DIF and DDF effects were explored for patterns. Comparisons of three methods for detecting DDF were conducted in this study. The standardized distractor analysis and odds-ratio methods for detecting DDF were found to have very highly related results, with regard to both the magnitude and pattern of DDF effects. The multinomial logistic regression DDF results also were highly related to the standardized distractor analysis approach, but yielded slightly different patterns across distractors. The odds ratio and multinomial logistic regression methods are easily implemented with available software, such as the SPSS software package used in this study, unlike the standardized distractor analysis method which must be programmed. Despite these and the other discussed differences, all three methods present a viable option for use in improving test items included in statewide assessment programs. / A Dissertation submitted to the Department of Educational Psychology and Learning Systems in partial fulfillment of the requirements for the degree of Doctor of Philosophy. / Spring Semester, 2010. / March 16, 2010. / Multinomial Logistic Regression, Standardization, Odds Ratio, Differential Distractor Functioning, Differential Item Functioning / Includes bibliographical references. / Betsy Jane Becker, Professor Co-Directing Dissertation; Akihito Kamata, Professor Co-Directing Dissertation; Adrian Barbu, University Representative; Jeannine Turner, Committee Member; Yanyun Yang, Committee Member.
183

Self-Presentational Concern as an Antecedent of Athletic Injury

Unknown Date (has links)
This study was an initial investigation of the relationship between self-presentational concern and chronic injury. An experiment with two manipulations was conducted to determine how situational self-presentational concerns affected expressions of toughness that may be linked to health-damaging behaviors that cause chronic injury. Covariates of self-presentational concerns and mental toughness were measured and determined to be equivalent across groups so that effects could be attributed to the manipulations. For a manipulation of situational self-presentational concerns, collegiate middle-distance and distance runners assigned to experimental groups read a passage. The passage was based on the components of a self-presentation model, impression motivation and impression construction. It indicated the need for runners to score high on toughness questionnaires to be evaluated favorably by coaches and governing bodies of the sport in order to achieve goals. All participants completed two questionnaires pertaining to mental toughness and tough attitude toward training through pain and injury. Expressions of mental toughness related to confidence and control were higher for participants exposed to heightened levels of situational self-presentational concerns than participants lacking the exposure. For a second manipulation, participants in one of the experimental groups were additionally exposed to a prototype describing the performance of the most successful runners on the mental toughness questionnaire. Expression of mental toughness of these participants did not differ significantly from other participants, failing to provide evidence of the prototype-matching process. Participants' expression of tough attitude toward training through pain and injury did not differ in relation to exposure to either manipulation. The results support the integration of self-presentational concerns related to mental toughness as a psychological antecedent in a model linking stressful, athletic situations and chronic injury. / A Thesis submitted to the Department of Educational Psychology and Learning Systems in partial fulfillment of the requirements for the degree of Master of Science. / Fall Semester, 2013. / October 31, 2013. / Impression Construction, Impression Motivation, Injury, Mental Toughness, Self-Presentation, Stress-Injury Model / Includes bibliographical references. / Robert Eklund, Professor Directing Thesis; Gershon Tenenbaum, Committee Member; Alysia Roehrig, Committee Member.
184

The Relationships Between Executive Functioning Deficits Related to ADHD and Mindfulness

Unknown Date (has links)
This study investigated the relationship(s) between deficits of executive functioning ability and mindfulness as measured by Barkley's Deficits in Executive Functioning Scale (BDEFS) and the Five Facet Mindfulness Questionnaire (FFMQ) respectively. ADHD is a disorder affecting millions of individuals, including children. Currently it is the most diagnosed of all childhood psychological disorders with about half of those diagnosed continuing to experience symptoms into adulthood (CDC, 2010). The psychological construct of ADHD has been redefined recently by Barkley, opening the door for new conceptualization and treatment options (Barkley 2012). ADHD has been described as being synonymous with deficits in EF (Barkley, 2012). The current study's purpose was to evaluate the relationship(s) that exist between deficits of EF and mindfulness as evaluated by two prominent measures. Findings of the current study suggest mindfulness is related to EF ability, regardless of ADHD status. Mindfulness, as measured by higher scores on the FFMQ, appears to predict fewer EF deficits, and lower total scores on the BDEFS. The current study also examined if gender or ADHD status might influence the relationship between ADHD and mindfulness and concluded that they do not. Finally, the study also evaluated if the FFMQ could predict ADHD status as accurately as the BDEFS. The research findings indicate that both measures are significant predictors of ADHD, with the BDEFS being slightly higher (77% compared to 66%). This study supports the notion that mindfulness training might represent a viable treatment option for those with ADHD. / A Dissertation submitted to the Department of Educational Psychology and Learning Systems in partial fulfillment of the requirements for the degree of Doctor of Philosophy. / Summer Semester, 2014. / May 9, 2014. / ADHD, Bdefs, Executive Functioning, Ffmq, Meditation, Mindfulness / Includes bibliographical references. / Frances Prevatt, Professor Directing Dissertation; Sandra Lewis, University Representative; Angela Canto, Committee Member; Shengli Dong, Committee Member.
185

Child Behavior Checklist Behavioral Profiles of Children with Autism Spectrum Disorders

Unknown Date (has links)
Behavior checklists have been utilized by psychologists since the early 1900's and continue to play integral roles in the screening and monitoring of behavior based disorders (Achenbach & Rescorla, 2001). The Achenbach System of Empirically Based Assessment - Child Behavior Checklist (CBCL) is one of the few widely used broad-based behavior rating scales that have excellent psychometric properties (Achenbach & Rescorla, 2001). Recent research has focused on the CBCL's ability to screen for behaviors associated with autism spectrum disorders (ASD; Bolte, Dickhunt, & Poustka., 1999; Duarte, Bordin, Oliveira, & Bird, 2003; Rescorla, 1988, Sikora, et al, 2008). A combination of increasing rates of ASD and the need for earlier identification has created an urgency to find broadband screening tools that identify accurately this group of individuals since ASD-specific screening tools are not readily available. Therefore, the purpose of this study was to determine if patterns of normative strengths and weaknesses on the subscales of the CBCL are similar for individuals with ASD, nonASD controls, and those clinic-referred for behavior disorders. Profile analysis was used to compare the behaviors of (a) individuals with ASD to their normal controls, and (b) individuals with ASD to individuals clinic-referred for behavior difficulties. Results revealed that individuals with ASD displayed significantly higher scores on seven out of the eight CBCL subscales when compared to their nonASD controls. When compared to individuals clinic-referred for behavior difficulties, the ASD group displayed significantly higher scores on two of the CBCL areas. These findings support the use of the CBCL as a screening tool. Implications and conclusions are discussed and areas for future research are provided. / A Dissertation submitted to the Department of Educational Psychology and Learning Systems in partial fulfillment of the requirements for the degree of Doctor of Philosophy. / Spring Semester, 2009. / November 21, 2008. / Behavior Profiles, ASD, Autism Spectrum Disorders, CBCL, Child Behavior Checklist / Includes bibliographical references. / Briley E. Proctor, Professor Directing Dissertation; Amy M. Wetherby, Outside Committee Member; Frances E. Prevatt, Committee Member; Stephen A. Rollin, Committee Member.
186

Career Indecision, Negative Career Thoughts, and Vocational Interest Structure of First-Generation and Other College Students

Unknown Date (has links)
This study examined career indecision, negative career thoughts, and vocational interest structure of first-generation and other college students. First-generation college students (FGCS) are those students whose parents or guardians did not attend college. Research has shown that these individuals are less academically prepared for college, have more difficulty acclimating to the college environment (Choy, 2001), and are more at risk for not completing a degree, with higher attrition rates than other students (Ishitani, 2006). Career and personal motivation can predict college adjustment and persistence for FGCS (Dennis et al., 2005); therefore, career problem solving and decision making is an important task for these individuals. The process of career decision making of college students has been a popular area of research, including career indecision, negative career thoughts, and Holland's structure of career interests. Being undecided affects individuals' career decision-making abilities and may influence their thinking about the career decision-making process (Saunders et al., 2000). Negative career thoughts have been correlated with anxiety (Newman et al., 1989), depression (Saunders, Sampson, Peterson, & Reardon, 2000), and self-worth (Judge & Locke, 1993). Screening for negative career thoughts and being able to address these cognitions with clients may lead to better well-being and success in college. John Holland (1997) has written about a set of primary and secondary constructs that allow career professionals to assess an individual's readiness for making a career decision (Reardon & Lenz, 1999) and supply counselors with additional tools for working with clients. In university student populations, low differentiation may impair one's ability to choose a field of interest (Holland, Gottfredson, & Nafziger, 1975), high coherence may improve prediction of future occupation (Holland, Gottfredson, & Baker, 1990), and high consistency may lead to higher rates of college persistence (Wiley & Magoon, 1982). The U.S. Census Bureau (2000) reported that, in 1999, those with a high school diploma received an average salary of $27,351, individuals with some college received an average salary of $31,988, and workers with college degrees made an average salary of $42,877. Therefore, FGCS are more likely to earn less in their lifetime because of their lower graduation rates. Post-graduation, these differences disappear. First-generation and other college graduates have similar employment rates and appear to make comparable salaries after receiving a bachelor's degree (Nunez & Cuccaro-Alamin, 1998). With the increase in numbers of first-generation college students entering universities (Hudson, Kienzl, & Diehl, 2007), research on the career processes of these students is warranted. The following research questions were identified for this study: 1. What differences exist between first-generation college students and other students enrolled in a career planning course in terms of career indecision, negative career thoughts, and structure of vocational interests? 2. Does first-generation college student status contribute to career indecision, negative career thoughts, and structure of vocational interests among college students enrolled in a career planning course? 3. What is the relationship between first-generation college student status and career decision state? To answer these questions, data were analyzed from 243 undergraduate students enrolled in a career planning course. Participants completed the Occupational Alternatives Question to measure career indecision, the Career Thoughts Inventory to assess for negative career thoughts, and the Self-Directed Search to determine vocational interest structure. A multivariate analysis of variance (MANOVA) was utilized to test the first research question, with no significant differences emerging between first-generation college students and other students. To examine the second research question, a hierarchical multiple regression was performed to determine the unique contribution of first-generation college student status in explaining variance in each dependent variable. This regression resulted in first-generation college student status accounting for no significant variance on any dependent variables. To test the third question, a MANOVA was conducted with two levels of independent variables (first-generation and other) and two dependent variables (OAQ and Satisfaction with Choice). This analysis also resulted in no significant differences between the two groups. A discussion of the findings, limitations of the study, and implications for research are presented. Recommendations for future research are many, as the results of this exploratory study are limited in their scope of generalizability and there is a wealth of additional research that can be conducted in order to further the knowledge of this specific population of college students. / A Dissertation submitted to the Department of Educational Psychology and Learning Systems in partial fulfillment of the requirements for the degree of Doctor of Philosophy. / Summer Semester, 2009. / June 26, 2009. / Career Development, Negative Career Thoughts, Career Indecision, First-Generation College Students / Includes bibliographical references. / James P. Sampson, Jr., Professor Directing Dissertation; Elizabeth Goldsmith, Outside Committee Member; Robert C. Reardon, Committee Member; Gary W. Peterson, Committee Member.
187

Trash Talk in a Competitive Setting: Impact on Self-Efficacy, Affect, and Performance

Unknown Date (has links)
The experimental design utilized in this study tested the phenomenon of trash talk as the pivotal component under investigation. Madden™ NFL 08 Football video-game players (N = 40; Mean age = 20.68, SD = 2.00) were randomly assigned to two conditions in which they participated in two games of Madden™ NFL 08 Football. In the first condition (Silent-Talk) players conducted their first game in complete silence, and in the second game players were permitted to trash talk. This scenario was reversed for condition two (Talk-Silent), players being permitted to talk in the first game, and enforced to be silent for game two. All players in the study completed 5 separate measures for; Madden™ NFL 08 Football Self-Efficacy, Positive Affect (PA), and Negative Affect (NA). Players also completed a short trash talk survey and made two specific choices prior to a hypothetical "Game 3" which was never played. Choices related to a player's ability to talk or remain silent, and whether to permit their opponent to talk or to enforce them to remain silent in "Game 3." Measurements were taken immediately prior to each game played, after players had received their instructions for the game (Talk or Silence), immediately after games 1 and 2 had been played, and finally before the hypothetical "Game 3," which was not played. Results confirmed that the ability and freedom to trash talk in a competitive setting is considered extremely important by Madden™ NFL 08 video-game players. Players were adamant that trash talking was a motivational tool, which they used when competing in the game; almost all (95%) players admitted to using trash talk in physical sports environments outside the milieu of computer gaming. RM ANOVAs revealed several significant (p < .05) results for the variables of interest (self-efficacy, positive affect, negative affect, and performance), but not all in line with the stated hypotheses. Contrary to expectations, performance measures for specific talk and silent games revealed no discernible differences for scoring, rushing, or passing. Although non-significant (p < .05) effects were noted for experimental conditions in overall performance measures, winners differed from losers on these variables. Winning performance resulted in significantly better overall performance measures across both games, with the exception of game 1 and rushing yards. Players enforced to be silent in the first game (Silent-Talk condition) instantaneously exhibited lower self-efficacy, lower PA, and higher NA than players permitted to talk in game 1. Players' self-efficacy remained relatively consistent after winning game 1. However, players subsequently instructed to remain silent in the second game showed markedly decreased self-efficacy compared to players permitted to talk in game 2. All the losers in game 1 reported decreased self-efficacy scores following a loss. However, players permitted to talk in the second game showed a significant increase in efficacy compared to players who lost and were also instructed to be silent in game 2. Prior to the hypothetical "Game 3," after players' trash talk choices (i.e., talk or silence in "Game 3", both personally and for an opponent) had been made, self-efficacy displayed a sharp increase for both experimental conditions and outcome (win/loss). Winners in the talk-silent condition decreased in PA after game 1 and prior to game 2, in which they had to remain silent. However, this decrease was more pronounced for losers who displayed a consistent downward trend in PA following game 1, and prior to game 2 in which they were to remain silent. Winners in the silent-talk condition exhibited a gradual increase in PA throughout the first three measures. Losers reported a slight decline after losing game 1, but a marked increase in PA after being instructed to talk in game 2. Both experimental conditions resulted in a significant increase in PA after trash talk choices were made prior to "Game 3." This was replicated for winners and losers who both showed increased PA after their trash talk choices. Elevation in NA was noted for both winners and losers after game 1, but this increase was more acute for losers. Players in both conditions showed an increase in NA after game 1, and both conditions showed a very similar decrease in NA immediately prior to game 2. Winners in both conditions maintained very similar NA scores across the first three measures, whereas losers showed an increase in NA after game 1, before finally decreasing immediately prior to game 2. Across both conditions winners' NA decreased following game 2, whilst losers perceived NA increased distinctly. After trash talk choices were made, losers' NA decreased, whilst winners' NA unexpectedly increased. The majority (95%) of players chose to be free to talk in "Game 3" of the study. Unexpectedly, many players preferred not to enforce silence upon their opponent for "Game 3." Players who did choose to enforce silence upon their opponent most commonly did so when they had been victorious in the silent game played, or they had lost both of their games. The majority of players in the study felt that their enforced silence had helped their opponent. However, several players who won the silent game believed their enforced silence had no effect on their opponent. The order in which the games were played (Talk-Silent or Silent-Talk) dramatically impacted the amount of trash talk used in the 'talk' games. The silent-talk condition resulted in 58% more coded trash talk occurrences than the talk-silent condition. Two conceivable reasons were the potential to reference game 1 as a source of conversation, and the reluctance of players to trash talk a total stranger. Overall, results reveal self-efficacy was impacted by the freedom to trash talk, and by winning and losing in line with the hypotheses outlined at the inception of this study. Specifically, when permitted to talk and when winning games players experienced personal autonomy, a sense of control, and positive mastery experiences, which are all key tenets of bolstering self-efficacy (Bandura, 1992, 1997). As self-efficacy changed due to experimental conditions and outcome there were simultaneous effects on both PA and NA, which echoes previous research on self-efficacy expectations as a mediator to changes in affect (Feltz & Lirgg, 2001). However, unlike self-efficacy, emotions (PA and NA) were less predictable and idiosyncratic, even when the outcomes or conditions were seemingly optimal (Boutcher, 1993; Robazza et al., 1998). Whereas self-efficacy measures appeared to remain contingent on experimental condition or outcome throughout the study, affect scores exhibited features which support the assertion that most significant emotions are invariably personal relevant, regardless of tangible outcomes (Hanin, 2000, 2007). / A Dissertation submitted to the Department of Educational Psychology and Learning Systems in partial fulfillment of the requirements for the degree of Doctor of Philosophy. / Fall Semester, 2008. / October 30, 2008. / Trash Talk, Trash Talk Competition, Talk Sport, Self-Efficacy, Affect, Performance Talk / Includes bibliographical references. / Gershon Tenenbaum, Professor Directing Dissertation; Robert C. Eklund, Committee Member; Alysia Roehrig, Committee Member; Robert Moffatt, Outside Committee Member.
188

The Relationships Among Negative Career Thoughts, Profile Elevation, Differentiation, Career Decidedness, and Satisfaction with Choice

Unknown Date (has links)
This study investigated the relationships among negative career thoughts and profile elevation, differentiation, career decidedness, and satisfaction with choice. Study participants were 226 university students enrolled in an Introduction to Career Development course. The Career Thoughts Inventory (CTI) was used to measure negative career thoughts, the Self-Directed Search (SDS) was used to measure profile elevation and differentiation, the Occupational Alternatives Question (OAQ) was used to measure career decidedness, and the Satisfaction with Choice item was used to determine participants' level of satisfaction with their first career choice. A series of multiple regression analyses were conducted to determine the amount of variance accounted for by negative career thoughts (decision-making confusion, commitment anxiety, and external conflict) in profile elevation, differentiation, career decidedness, and satisfaction with choice. Negative career thoughts were found to account for a significant amount of variance in profile elevation, career decidedness, and satisfaction with choice. In addition, exploratory analyses were conducted to examine the interaction of decision-making confusion, commitment anxiety, and external conflict on the criterion variables. No significant interaction effects were found for the analyses with profile elevation or differentiation as the criterion variables. With regard to career decidedness, a significant three-way interaction was indicated, and the three main effects and three two-way interactions as a set were significant with satisfaction with choice as the criterion variable. Results of this study support the inverse relationship between career decidedness, satisfaction with choice, and negative career thoughts. Findings suggest the need to fully explore negative thinking that interferes with clients making effective career decisions. / A Dissertation submitted to the Department of Educational Psychology and Learning Systems in partial fulfillment of the requirements for the degree of Doctor of Philosophy. / Summer Semester, 2011. / July 6, 2010. / Negative Career Thoughts, Profile Elevation, Differentiation, Decidedness / Includes bibliographical references. / James P. Sampson, Jr., Professor Co-Directing Dissertation; Janet Lenz, Professor Co-Directing Dissertation; Chris Schatschneider, University Representative; Steven Pfeiffer, Committee Member.
189

The Sequential Analysis of Collaborative Writing and Editing Processes in Wikis

Unknown Date (has links)
The purpose of this study was to sequentially analyze and identify collaborative writing processes used to increase or decrease the quality of students' written arguments. The study's participants were 16 graduate students enrolled in an online course on inquiry and measurement. Every student worked on one team to analyze the arguments for using surveys and worked on one team to analyze arguments for using interview. A total of seven teams worked on the survey arguments; seven teams worked on the interview arguments. Each student worked with their team members using their team's own wiki to analyze and develop each argument for using surveys and interviews. The arguments produced by the students were scored by the researcher and a second coder to determine which processes performed by the consenting students produced the highest- and lowest-quality arguments. Results indicated that the collaborative writing process used by students working in teams to develop a high-quality argument in a wiki consisted of six action sequence patterns while teams producing a low-quality argument consisted of only two action sequence patterns. Given that the low-quality argument action sequences were also not observed in the processes used to produce the high-quality arguments, it is possible that these two action sequences have hindered or obstructed the processes needed to produce high-quality arguments. The findings indicate that specific action sequences and more structured collaborative writing processes may help to produce high-quality arguments. As a result, interventions should be directed at increasing the frequency of the action sequences found in this study to produce high-quality arguments which may assist students in writing higher quality arguments. / A Dissertation submitted to the Department of Educational Psychology and Learning Systems in partial fulfillment of the requirements for the degree of Doctor of Philosophy. / Summer Semester, 2014. / April 15, 2014. / Collaborative Writing, Editing, Measurement, Sequential Analysis, Teams, Wikis / Includes bibliographical references. / Allan Jeong, Professor Directing Dissertation; Ulla Sypher, University Representative; Vanessa Dennen, Committee Member; Robert Reiser, Committee Member.
190

The Estimation and Specification Search of Structural Equation Modeling Using Frequentist and Bayesian Methods

Unknown Date (has links)
Structural equation modeling (SEM) refers to statistical analyses of the relationships among observed and latent variables based on hypothesized models. In reality, proposed models are rarely perfect, specification search is conducted to correct specification errors between the proposed and population models. Both frequentist and Bayesian methods have strength and limitations in the estimation and specification search of SEM models. Estimation problems that arise from the violation of distributional and/or structural assumptions have not been thoroughly studied. Performance of specification search methods based on different theoretical framework has rarely been compared. Two purposes of this study were: (1) to investigate robust maximum likelihood (RML) and three Bayesian methods for estimating confirmatory factor analysis models under imperfect conditions, and (2) to compare modification index (MI) and Bayesian structural equation modeling (BSEM) in search of cross-loadings in factor analysis models. Two Monte Caro studies were designed for model estimation (Study 1) and specification search (Study 2), respectively. Both studies replicated 2000 datasets for each condition. Design factors included sample size, factor structure, loading size, and item distribution. Study 1 analyzed both correctly specified and misspecified models. Results were evaluated based on model fit, parameter estimates, and standard errors. Study 2 searched for omitted 1, 2, and 4 cross-loadings in data generation models. The evaluation of results focused on the success of specification search and model evaluation. Results showed that the frequentist chi-square test was more powerful than the Bayesian posterior predictive p-value test. Bayesian methods specified with appropriate priors provided accurate parameter estimates similar to RML even under moderate violation of SEM assumptions. Practically however, the selections of Bayesian priors on hypothesized models need to be exceptionally cautious, because they are likely to interact with sample sizes, data distribution, and degree of model misspecification. In specification search, MI generally provided higher model recovery rates than BSEM under the designed conditions. BSEM led to considerable false positive solutions as sample size increased if informative priors were not properly selected. However, MI is not always preferable. The study recommended that practical selections of Bayesian priors may be based on 95% parameter coverage. Future research will investigate the sensitivity of various Bayesian priors in specification search. / A Dissertation submitted to the Department of Educational Psychology and Learning Systems in partial fulfillment of the requirements for the degree of Doctor of Philosophy. / Summer Semester, 2014. / June 17, 2014. / Includes bibliographical references. / Yanyun Yang, Professor Directing Dissertation; Fred Huffer, University Representative; Betsy Jane Becker, Committee Member; Insu Paek, Committee Member.

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