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Dimensions of Social Network Position As Predictors of Employee Performance.

Description: Research of social networks has revealed that certain components of network position can have an impact on organizational effectiveness, yet relatively little research has been conducted on network position and individual performance. This study sought to determine if a relationship exists between an employee's social network position and an individual's job performance. The participant organization was a network of individuals within an Information Technology (IT) department at a major defense company. A social network analysis (SNA) was conducted to determine the employee's network position, measured by centrality and constraint. Centrality refers to the extent to which an individual is connected to others. Constraint refers to how constrained or inhibited an individual is within the network. Performance was measured by annual appraisal ratings provided by the employee's supervisor. Hierarchical regression analysis was performed to determine relationships between the dependent variable (performance) and independent variables of centrality and constraint. Secondary variables also studied in relation to the model included education level, service years (tenure), job grade, and age. The overall model revealed 17% of variance explained. The primary predictors of network position, centrality and constraint, were not statistically significant predictors of performance ratings. Three variables, job grade, tenure and age, were found to be statistically significant predictors of employee performance. Further research is suggested to provide additional insight into the predictive value of these variables.
Date: August 2007
Creator: Burton, Paul

A Quantitative Modeling Approach to Examining High School, Pre-Admission, Program, Certification and Career Choice Variables in Undergraduate Teacher Preparation Programs

Description: The purpose of this study was to examine if there is an association between effective supervision and communication competence in divisions of student affairs at Christian higher education institutions. The investigation examined chief student affairs officers (CSAOs) and their direct reports at 45 institutions across the United States using the Synergistic Supervision Scale and the Communication Competence Questionnaire. A positive significant association was found between the direct report's evaluation of the CSAO's level of synergistic supervision and the direct report's evaluation of the CSAO's level of communication competence. The findings of this study will advance the supervision and communication competence literature while informing practice for student affairs professionals. This study provides a foundation of research in the context specific field of student affairs where there has been a dearth of literature regarding effective supervision. This study can be used as a platform for future research to further the understanding of characteristics that define effective supervision.
Date: December 2007
Creator: Williams, Cynthia Savage

Teacher Turnover among Teachers of Students with Emotional and Behavior Disorders

Description: The purpose of this study was to investigate factors that compel teachers of students with emotional and behavioral disorders (E/BD) to quit or stay in their job. Invitations to participate in the study were sent to a sample of educators from each the four census regions of the United States who currently work or have worked in the past worked with students with E/BD and have participated in one or more of the Council for Children with Behavioral Disorders (CCBD) professional development events. A total of 156 educators responded to the online survey and 9 participated in the focus groups. Quantitative information generated from the survey was analyzed using frequency distributions and ANOVA, whereas, qualitative information were analyzed by summarizing and sorting information into different categories. The results were presented in narrative and tabular form and organized in response to each of the research questions. The projected high teacher turnover as depicted in the findings, were mainly attributed to workplace variables and classroom conditions. Both variables are likely to be associated with high levels of dissatisfaction and lack of commitment eventually leading to decisions by teachers of students with E/BD to leave their job. Most respondents perceived themselves as being adequately prepared for responsibilities associated with teaching students with E/BD. The low variances associated with the grouping variable, career decisions did not explain a significant amount of variance in perceived levels of preparedness with regards to implementation of various program components and instructional activities. Hence, teacher qualifications and perceptions did not play a significant role in career decisions made by teachers of students with E/BD. In addition, findings reveal the need for all future teachers regardless of their certification to take specialized courses in special education to ensure that all teachers understand the unique characteristics and needs of students with ...
Date: December 2007
Creator: Adera, Beatrice Atieno

A follow-up study of a masters program for teachers of students with emotional/behavioral disorders.

Description: Educators today are faced with a worthy goal. Every student, including those with emotional and behavioral disorders (EBD), must be taught by a qualified teacher. However, recruiting, training, and retaining quality special education teachers continue to confound the field. The purpose of this study was to determine if the completion of a NCATE/CEC (National Council for Accreditation of Teacher Education/Council for Exceptional Children) approved masters program specializing in EBD from a well-known university increased the confidence in knowledge and skills of special educators, the numbers of special educators, and/or the retention of special educators working with students with EBD. The sample in this study was composed of 199 students who had completed the master's degree in special education who specialized in emotional/behavioral disorders from 1985 to 2005. Data were compiled from 80 students at a response rate of approximately 40%. Additionally, five respondents participated in face-to-face interviews. The data did not lend themselves to the quantitative analysis and thus pose a limitation to the generalizability of this study. However, combined with the qualitative analysis, the study provided a rich analysis of a program whose graduates stay in the field of special education providing services to students with EBD.
Date: August 2008
Creator: Walter, Paulette C.

Heard but not seen: Instructor-led video and its effect on learning.

Description: Educators and instructional designers are seeking ways to increase levels of learning. One of the ways this is being done is through cognitive load theory which attempts to reduce cognitive load through a better understanding of working memory and the factors that impact its function. Past studies have found that working memory processes visual and auditory information using separate and non-sharable resources (dual coding theory) and that by properly utilizing multimedia elements, information processing in working memory is more efficient (multimedia learning). What is not known is the effect that instructor-led video, which uses the visual channel but delivers no information, has on the cognitive load of the learner. Further, will the introduction of multimedia elements make the information processing of the learner more efficient? This study examined three ways in which instructional designers may create a more efficient learning environment through a better understanding of multimedia learning. First, by using the theories of multimedia learning, I examined a more efficient use of sensory memory. By minimizing extraneous load, which communication theory calls noise, on working memory through increased utilization of the visual and auditory channels, the effectiveness of instruction was increased. Secondly, the multimedia effect, defined as using visual helps and guides with spoken and written text, was shown to assist working memory in processing new information into existing schema. Last, by using the personalization principle set forth by Clark and Mayer (2008), I used both the video feed and multimedia together to foster a more social or conversational presentation to the learner.
Date: August 2008
Creator: Holder, David E.

Frequency and quality of the implementation of functional behavioral assessments as reported by educators.

Description: The research investigation reported herein examined the quality and experience of the functional behavioral assessment (FBA) process as reported by educators working with students with emotional/behavioral disorders (EBD). The data accrued is based on a 30-item survey and participant telephone interviews examined the overall knowledge of the FBA process by educators and their general experience when conducting a FBA, specifically the procedural timeline, types of education professionals involved, and typical outcomes and results. Survey responses indicated two common barriers in the FBA implementation which often inhibit best practice: lack of true collaborative teamwork and insufficient communication among FBA team members. Survey responses also indicated a level of statistical significance from education professionals working in elementary school settings who self-rated positively higher when conducting a FBA than those education professionals working on either a secondary or special campus. Additionally, participant interviews indicated a growing awareness of the advantages of using the FBA as an early intervention process when dealing with challenging behaviors.
Date: December 2008
Creator: Moreno, Gerardo

Investigating the hypothesized factor structure of the Noel-Levitz Student Satisfaction Inventory: A study of the student satisfaction construct.

Description: College student satisfaction is a concept that has become more prevalent in higher education research journals. Little attention has been given to the psychometric properties of previous instrumentation, and few studies have investigated the structure of current satisfaction instrumentation. This dissertation: (a) investigated the tenability of the theoretical dimensional structure of the Noel-Levitz Student Satisfaction Inventory™ (SSI), (b) investigated an alternative factor structure using explanatory factor analyses (EFA), and (c) used multiple-group CFA procedures to determine whether an alternative SSI factor structure would be invariant for three demographic variables: gender (men/women), race/ethnicity (Caucasian/Other), and undergraduate classification level (lower level/upper level). For this study, there was little evidence for the multidimensional structure of the SSI. A single factor, termed General Satisfaction with College, was the lone unidimensional construct that emerged from the iterative CFA and EFA procedures. A revised 20-item model was developed, and a series of multigroup CFAs were used to detect measurement invariance for three variables: student gender, race/ethnicity, and class level. No measurement invariance was noted for the revised 20-item model. Results for the invariance tests indicated equivalence across the comparison groups for (a) the number of factors, (b) the pattern of indicator-factor loadings, (c) the factor loadings, and (d) the item error variances. Because little attention has been given to the psychometric properties of the satisfaction instrumentation, it is recommended that further research continue on the SSI and any additional instrumentation developed to measure student satisfaction. It is possible that invariance issues may explain a portion of the inconsistent findings noted in the review of literature. Although measurement analyses are a time-consuming process, they are essential for understanding the psychometrics characterized by a set of scores obtained from a survey, or any other form of assessment instrument.
Date: December 2008
Creator: Odom, Leslie R.

An Analysis of Job Satisfaction for Special Educators Who Instruct Students with Emotional/Behavioral Disorders: How Working Conditions Impact Commitment.

Description: Teachers of students with emotional/behavioral disorders (E/BD) find that myriad concerns for effective teaching (e.g., salaries, increased paperwork, classroom management) challenge their ability to meet personal and professional needs. The push for certified teachers and limited training to work with students with special needs create stressors that can prohibit effective teaching in the workplace. Teacher moral drops and half of newly hired employees leave the profession. Equally important, student outcomes are affected. Demographic information, program practices, and commitment information from special education teachers across the country were examined in this study. These areas of study helped to determine the best indicators for teacher job satisfaction and barriers that threaten satisfactory working conditions. An online survey was designed to capture 29 areas to explore qualifications and working environments for these teachers. Of the 600 targeted teachers, 332 individuals participated in Likert-like scales to determine their degree of satisfaction or dissatisfaction for working conditions, use of intervention strategies, and areas of commitment. Closed-ended and multiple-choice questions were used. Descriptive analyses and tables aided in understanding this study. The resulting factors indicated that, although some respondents pointed to job dissatisfaction within the subset of questions, participants who worked for more than 6 years were less likely to vacate their positions than teachers working for less than six years.
Date: August 2009
Creator: Adkins, Beverly

The Effects of Positive Behavioral Supports in Schools since the Implementation of the Individuals with Disabilities Education Act of 1997 based on 2001 SLIIDEA Data

Description: Congress in 1997 recognized that there were some issues and concerns that had emerged surrounding the Individuals with Disabilities Education Act (IDEA) and sought to address these issues and concerns by mandating a national evaluation on the implementation and progress toward improving outcomes for students with disabilities. The Study of the State and Local Implementation of the Individuals with Disabilities Education Act was designed to address how the amendments of IDEA were being implemented by states, school districts, and schools. This mixed methods study examined the first year of data collected from the six-year Study of the State and Local Implementation of IDEA (SLIIDEA) and analyzing 20 case studies that used interviews of special education personnel and principals, conducted at the local school level. Data from the national survey were examined in light of findings from the case studies. The case studies brought out the varying opinions on implementation success at the local level. Further case studies for each year of the study would be helpful in determining the level of implementation locally and the significant insights of local school personnel on whether these initiatives have worked.
Date: August 2009
Creator: Miller, Cindy

Stratified item selection and exposure control in unidimensional adaptive testing in the presence of two-dimensional data.

Description: It is not uncommon to use unidimensional item response theory (IRT) models to estimate ability in multidimensional data. Therefore it is important to understand the implications of summarizing multiple dimensions of ability into a single parameter estimate, especially if effects are confounded when applied to computerized adaptive testing (CAT). Previous studies have investigated the effects of different IRT models and ability estimators by manipulating the relationships between item and person parameters. However, in all cases, the maximum information criterion was used as the item selection method. Because maximum information is heavily influenced by the item discrimination parameter, investigating a-stratified item selection methods is tenable. The current Monte Carlo study compared maximum information, a-stratification, and a-stratification with b blocking item selection methods, alone, as well as in combination with the Sympson-Hetter exposure control strategy. The six testing conditions were conditioned on three levels of interdimensional item difficulty correlations and four levels of interdimensional examinee ability correlations. Measures of fidelity, estimation bias, error, and item usage were used to evaluate the effectiveness of the methods. Results showed either stratified item selection strategy is warranted if the goal is to obtain precise estimates of ability when using unidimensional CAT in the presence of two-dimensional data. If the goal also includes limiting bias of the estimate, Sympson-Hetter exposure control should be included. Results also confirmed that Sympson-Hetter is effective in optimizing item pool usage. Given these results, existing unidimensional CAT implementations might consider employing a stratified item selection routine plus Sympson-Hetter exposure control, rather than recalibrate the item pool under a multidimensional model.
Date: August 2009
Creator: Kalinowski, Kevin E.

Analysis of School Discipline with a Focus on Characteristics of Hispanic Adolescents with Learning Disabilities from a Low-Socioeconomic Area

Description: The research reported herein examined the emotional and behavioral characteristics of adolescent Hispanic students with and without learning disabilities from a middle school in north central Texas. The data were based on all students enrolled at the campus (N = 986), but focused on 55 students of Hispanic descent with learning disabilities and 55 students without. The data accrued for this study utilized a school discipline database. In addition, a 43-item behavioral rating scale was completed on each student of the more focused group. Methods of data analysis were derived from descriptive statistics, one-way analysis of variance, and multiple regression measurements. The results indicate that Hispanic students with learning disabilities often exhibit more disruptive behaviors.
Date: December 2009
Creator: Garcia-Rodriguez, Gina D.

Comparing the Effects of Home Versus Clinic-Based Parent Training for Children with Autism

Description: Research with parents on managing child problem behavior typically measures either child or parent behavior. This study was designed to evaluate the effectiveness of training parents to implement a function-based behavior intervention plan (BIP) in a non-trained natural environment utilizing a Multiple Probe Design across Participants. Participants included four parent-child dyads. Measurement variables included parents' use of effective and ineffective strategies and child problem behavior. Intervention involved training parents to understand and implement the BIP using effective strategies, modeling the effective procedures, and providing feedback following parent implementation of procedures. Results showed that the intervention was very effective in promoting skill generalization of parents and decreasing child problem behavior. The findings have implications for research and clinical practice.
Date: May 2010
Creator: Crone, Regina M.

Determination of the Optimal Number of Strata for Bias Reduction in Propensity Score Matching.

Description: 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

Alternative Certification: A Comparison of Factors Affecting the Motivations of General and Special Educators

Description: This study was developed to examine the motivations of individuals who chose alternative routes to teacher certification and what they believe were the strengths and weaknesses of their alternative certification preparation (ACP). Data accrued from this study were based on a 55-item online survey and participant information from an online focus group. The study compared the differences between general and special educators in regards to the motivating factors affecting the decision to become a teacher, remain a teacher, and in choosing a non-university-based ACP, as well as the perceived strengths and weaknesses of the ACP. The results from the survey suggest there are differences in the motivating factors affecting general and special educator's decision to become a teacher and to remain a teacher. Additional survey results suggest there are no differences in the reason these two groups chose a non-university-based ACP. The results of the survey and the online focus group were comparable for these two groups. The remainder of this dissertation includes a review of literature related to teacher shortages and teacher preparation including alternative certification. Additionally, information on the results and analysis of the study are discussed, as well as recommendations for future research.
Date: August 2010
Creator: Hogan, Kathleen Ann

Attenuation of the Squared Canonical Correlation Coefficient Under Varying Estimates of Score Reliability

Description: Research pertaining to the distortion of the squared canonical correlation coefficient has traditionally been limited to the effects of sampling error and associated correction formulas. The purpose of this study was to compare the degree of attenuation of the squared canonical correlation coefficient under varying conditions of score reliability. Monte Carlo simulation methodology was used to fulfill the purpose of this study. Initially, data populations with various manipulated conditions were generated (N = 100,000). Subsequently, 500 random samples were drawn with replacement from each population, and data was subjected to canonical correlation analyses. The canonical correlation results were then analyzed using descriptive statistics and an ANOVA design to determine under which condition(s) the squared canonical correlation coefficient was most attenuated when compared to population Rc2 values. This information was analyzed and used to determine what effect, if any, the different conditions considered in this study had on Rc2. The results from this Monte Carlo investigation clearly illustrated the importance of score reliability when interpreting study results. As evidenced by the outcomes presented, the more measurement error (lower reliability) present in the variables included in an analysis, the more attenuation experienced by the effect size(s) produced in the analysis, in this case Rc2. These results also demonstrated the role between and within set correlation, variable set size, and sample size played in the attenuation levels of the squared canonical correlation coefficient.
Date: August 2010
Creator: Wilson, Celia M.

Educators' Perceptions of the Importance of Selected Competencies for Teachers of Students with Emotional and Behavioral Disorders and their Perceptions of Personal Proficiency

Description: This study investigated educators' perceptions of the importance of competencies for teachers of students with emotional and behavioral disorders and their own proficiency in the competencies. Participants included educators who had completed university-based coursework on emotional and behavioral disorders. Competencies from the Qualification and Preparation of Teachers of Exceptional Children study were correlated with CEC's content standards and knowledge skill sets for special education teachers of individuals with emotional and behavioral disorders. Participants ranked 88 competencies on importance and proficiency. Results revealed that educators' proficiency in competencies, their years of experience, and level of education contribute a significant percentage of variance in their ratings of the importance of competencies. Implications for further research are provided.
Date: December 2010
Creator: Wanyonyi-Short, Maureen N.

Effects of the Why Try Social Skills Program on Students with Emotional and Behavioral Disorders at an Alternative Campus

Description: Approximately 20% of students with emotional and behavioral disorders (E/BD) are sent to an alternative campus for their lack of social competence. Social skills training (SST) is an evidence-based intervention to help increase social competence for students with E/BD, but there is limited research that addresses SST for students with E/BD at alternative campuses. A mixed-methods design was utilized to examine SST at an alternative campus for students with E/BD. Pre-intervention data were collected for students' attendance, grades, office disciplinary referrals, and behavioral rating scales, after which, the Why Try SST program was implemented. Following the intervention, the same type of data were collected. Nonparametric statistics guided the quantitative analysis, because of the small population being studied. Differences from pre- to post-intervention were examined. Triangulation methods drove the qualitative data collection and analysis through observations, student interviews, and teacher interviews. Students exhibited significant differences from pre- to post-intervention in the number of office disciplinary referrals and several areas on the behavioral rating scales. Important insight into motivation and perceptions was gained through the observations and interviews.
Date: December 2010
Creator: Wilhite, Shannon

A Hierarchical Regression Analysis of the Relationship Between Blog Reading, Online Political Activity, and Voting During the 2008 Presidential Campaign

Description: The advent of the Internet has increased access to information and impacted many aspects of life, including politics. The present study utilized Pew Internet & American Life survey data from the November 2008 presidential election time period to investigate the degree to which political blog reading predicted online political discussion, online political participation, whether or not a person voted, and voting choice, over and above the predication that could be explained by demographic measures of age, education level, gender, income, marital status, race/ethnicity, and region. Ordinary least squares hierarchical regression revealed that political blog reading was positively and statistically significantly related to online political discussion and online political participation. Hierarchical logistic regression analysis indicated that the odds of a political blog reader voting were 1.98 the odds of a nonreader voting, but vote choice was not predicted by reading political blogs. These results are interpreted within the uses and gratifications framework and the understanding that blogs add an interpersonal communication aspect to a mass medium. As more people use blogs and the nature of the blog-reading audience shifts, continuing to track and describe the blog audience with valid measures will be important for researchers and practitioners alike. Subsequent potential effects of political blog reading on engagement, discussion, and participation will be important to understand as these effects could impact the political landscape of this country and, therefore, the world.
Date: December 2010
Creator: Lewis, Mitzi

Knowledge and Confidence of Speech-Language Pathologists Regarding Autism

Description: The increased prevalence rate of autism has immense implications for speech language pathologists (SLPs) who are directly involved in the education and service delivery for students with autism. However, few studies have documented the effectiveness of the knowledge and confidence of SLPs regarding autism. The purpose of this study was to measure the knowledge and confidence of SLPs regarding autism and the extent to which their educational and professional training prepared them to work effectively with this population. An online survey was administered to and returned by 336 SLPs nation-wide. Two multiple linear regressions were conducted to determine the variables that explained overall knowledge and confidence. The number of students with autism on one's caseload explained most of the variance. Independent sample t-test results depicted knowledge and confidence scores of SLPs who were behaviorally trained versus those who were not behaviorally trained. SLPs who were behaviorally trained had higher mean scores on measures of knowledge and confidence when compared to those without formal behavioral training. Finally, a bivariate correlation was conducted to explore the relationship between knowledge and confidence of SLPs, however, results were not statistically significant.
Date: December 2010
Creator: Ray, Julie M.

Knowledge and Training in Autism Spectrum Disorders Among Special Education Administrators.

Description: A significant rise in the number of students with autism spectrum disorders (ASD) served in today's schools requires special education administrators to possess knowledge in this area. The purpose of this study was to determine the general knowledge of special education administrators concerning ASD and knowledge of educational programming, to explore their educational training and professional development experiences in ASD, to identify the training needs of special education administrators in ASD, and to determine if knowledge, training and experience in ASD predict litigation. Using survey methods, data were collected from a sample of 106 special education administrators in Texas. Data revealed special education administrators were most knowledgeable of general characteristics, common myths, and instructional strategies, and less knowledgeable of eligibility criteria. Knowledge regarding educational programming for learners with ASD produced mixed results. Logistic regression analysis revealed general autism knowledge, knowledge of educational programming, training, and experience in ASD were not factors predicting litigation. Although results indicated none of the factors explored in this study were predictors of litigation, areas of need regarding professional development were identified. Implications for future research are also discussed.
Date: December 2010
Creator: Hughes, Heather L.

Spatial Ability, Motivation, and Attitude of Students as Related to Science Achievement

Description: Understanding student achievement in science is important as there is an increasing reliance of the U.S. economy on math, science, and technology-related fields despite the declining number of youth seeking college degrees and careers in math and science. A series of structural equation models were tested using the scores from a statewide science exam for 276 students from a suburban north Texas public school district at the end of their 5th grade year and the latent variables of spatial ability, motivation to learn science and science-related attitude. Spatial ability was tested as a mediating variable on motivation and attitude; however, while spatial ability had statistically significant regression coefficients with motivation and attitude, spatial ability was found to be the sole statistically significant predictor of science achievement for these students explaining 23.1% of the variance in science scores.
Date: May 2011
Creator: Bolen, Judy Ann

Structural Validity and Item Functioning of the LoTi Digital-Age Survey.

Description: The present study examined the structural construct validity of the LoTi Digital-Age Survey, a measure of teacher instructional practices with technology in the classroom. Teacher responses (N = 2840) from across the United States were used to assess factor structure of the instrument using both exploratory and confirmatory analyses. Parallel analysis suggests retaining a five-factor solution compared to the MAP test that suggests retaining a three-factor solution. Both analyses (EFA and CFA) indicate that changes need to be made to the current factor structure of the survey. The last two factors were composed of items that did not cover or accurately measure the content of the latent trait. Problematic items, such as items with crossloadings, were discussed. Suggestions were provided to improve the factor structure, items, and scale of the survey.
Date: May 2011
Creator: Mehta, Vandhana

Teachers' Perspectives on Student Problematic Behavior and Social Skills

Description: The research investigation reported herein examined program outcomes of student problem behavior and social skills, based on teachers' perspectives, before and after early behavioral intervention services. The study targets students in kindergarten through grade five who are identified by the school system for being at-risk for being labeled with emotional and behavioral disorders. Students identified received early intervention services based on individualized positive behavioral supports (i.e., social skills training, functional behavioral assessment, and team collaboration). Teachers completed a teacher form of the Social Skills Rating System before and after the student received program services to determine differences in social skills and problematic behavior pre- and post- program early intervention services. An analysis was also made of the differences among gender, ethnicity, and grade according to the teachers' perspectives. Data indicated statistically significant results in the area of social skills and problem behavior. The results indicate early intervention services that teach social skills and use functional behavioral assessments to deal with problem behavior are beneficial to children displaying behavior challenges.
Date: May 2011
Creator: Riney, Summer Sides

Missing Data Treatments at the Second Level of Hierarchical Linear Models

Description: The current study evaluated the performance of traditional versus modern MDTs in the estimation of fixed-effects and variance components for data missing at the second level of an hierarchical linear model (HLM) model across 24 different study conditions. Variables manipulated in the analysis included, (a) number of Level-2 variables with missing data, (b) percentage of missing data, and (c) Level-2 sample size. Listwise deletion outperformed all other methods across all study conditions in the estimation of both fixed-effects and variance components. The model-based procedures evaluated, EM and MI, outperformed the other traditional MDTs, mean and group mean substitution, in the estimation of the variance components, outperforming mean substitution in the estimation of the fixed-effects as well. Group mean substitution performed well in the estimation of the fixed-effects, but poorly in the estimation of the variance components. Data in the current study were modeled as missing completely at random (MCAR). Further research is suggested to compare the performance of model-based versus traditional MDTs, specifically listwise deletion, when data are missing at random (MAR), a condition that is more likely to occur in practical research settings.
Date: August 2011
Creator: St. Clair, Suzanne W.