Dissertationen zum Thema „Special methods of evidence“

This work explores how the evidential value of digital timestamps can be enhanced by taking a hypothesis based approach to the investigation of digital timestamps. It defines the concepts of clock hypotheses, timestamps and causality in digital systems. These concepts are utilized to develop methods that can be used in an investigation to test a clock hypothesis for consistency with timestamps found in an actual investigation, given causality between specific events occurring in the investigated system. Common storage systems are explored for the identification of causality between the events of information storage. By using a logic programming variant of predicate calculus, a formalism for modelling the relationship between events and timestamp updating is defined. This formalism can be used to determine invariants in digital systems.

Invariants and causality relations can be used to check a clock hypothesis for consistency with timestamp evidence. These methods can be utilized in software for digital investigation. By checking the large number of timestamps typically occurring on a digital medium, the methods can assist with the justification of a clock hypothesis, and thereby increase the confidence in specific timestamps found during the investigation. Previously, the checking of timestamps has relied upon the existence of timestamps from other evidence sources. With the methods defined in this work, justification of timestamp interpretation can be achieved without having to rely on timestamps from other sources of evidence.

The methods developed in this work were implemented in a clock hypothesis consistency checker. This checker was tested in an experiment where subjects were asked to antedate a document. The checker was found to be able to produce evidence supporting a hypothesis that the document was antedated.

Currently, the majority of students with disabilities are educated in a general education classroom, which led to a paradigm shift and pedagogies used to meet the needs of all students. The research problem was that general education teachers use of highly effective evidence-based interventions that improve academic achievement for students with disabilities was unknown, and it was not known why some teachers did not use these practices more frequently. The purpose of the study was to discover how frequently general education teachers implemented highly effective evidence-based interventions to improve academic achievement for students with disabilities, and why some teachers did not use these interventions. Bandura’s Social Learning Theory and Vygotsky’s Sociocultural Learning Theory were the framework for the study. A qualitative research approach using 30 videotaped lessons from the Measures of Effective Teaching Longitudinal study and 18 teacher interviews were used to answer the research questions. Videotaped lessons were scored for the use of highly effective evidence-based interventions that improve academic achievement for students with disabilities. Structured teacher interviews included the use of highly effective evidence-based practices, how frequently these practices were used weekly, and barriers that prevented them from using these best practices. Analysis of the frequency of use for highly effective evidence-based practices indicated that 90% of the teachers in the videos used explicit instruction, 27% used graphic organizers, and 10% used peer tutoring. Nonetheless, analysis of teacher interviews indicated explicit instruction and peer-tutoring were used by 100% of the teachers, 94% used reading comprehension strategies, 83% used inquiry based learning, 78% used graphic organizers, and mnemonics were used by 72% of the teachers. Barriers to implementing evidence-based practices were lack of time, money, resources, and efficacy to choose evidence-based practices for students with disabilities. Schools need to provide shared planning time, make better use of resources, and provide teacher training to build teachers’ efficacy to implement these best practices. Further research is recommended on the use of evidence-based practices in general education classrooms for students with disabilities using a larger sampling of general education teachers to increase the reliability and validity of the findings.

The disproportionate nature of special education, notably with African American students, is longstanding and most pronounced in judgmental eligibility categories such as intellectual disability and emotional disturbance. Numerous studies on disproportionality conclude there is not a single causative factor, but point to the multifactorial nature of the issue and the complex interplay among different factors. Research related to the role social factors exhibited in an institution have on special education referral and eligibility determination is more limited. This is important since practices employed during the eligibility process take place within the institution?s social environment and are underpinned by the beliefs and values of those that administer the process. By employing a mixed methods study design, the author examined the following questions: 1) are minority students, particularly African American elementary school students, more likely to be disproportionately represented in special education eligibilities across school districts in the county, and if so which ones; 2) within the referral and eligibility process employed, what criteria are used to determine the eligibility emotional disturbance; and 3) do the commonly held perceptions and practices present within the school district?s culture influence the process and decision-making for eligibility? Quantitative data were obtained from appropriate Illinois State Board of Educations (ISBE) websites and through a Freedom of Information Act request to the State Board of Education for specific data and statistics related to the special education population for 116 elementary school districts in a suburban midwestern county. Data showed 11 school districts demonstrated disproportionality, a risk ratio >3.0, for years 2011-2013. Of these, eight involved the African American student, with six school districts disproportionality centered on emotional disturbance thereby qualifying as potential candidates for Phase 2. Important to note, unlike previous research on disproportionality that examined school districts with predominantly Caucasian or even more diverse student populations, this study?s school district was primarily Hispanic, 94%, with African Americans making up 2% of students. This provided a unique opportunity to study two minority populations. The second phase of the study employed a qualitative approach of in-depth, semi-structured face-to-face interviews of key professionals involved in special education eligibility determination from the selected school district. Findings revealed two broad points related to the social environment of the school district that appeared to impact the referral and eligibility process. First is the strength of administrative leadership vis-a-vis process implementation and second is the sociocultural environment of the district. In this case, leadership was passive when it came to ensuring fidelity to tiered intervention plans, a critical component of the referral process. Basically leadership allowed fidelity and accountability to the intervention process by teachers to be lackluster at best or worst case absent. Consequently, teachers more resistant to engaging in the intervention process tended have higher student referrals. The sociocultural environment of the school district studied is comprised basically of two divergent economic classes, the middle class predominately Caucasian educators/administrators and the student population who are of low to very low economic status and predominately of two racial/ethnic minorities. Comments consistently emerged from interviewees regarding differences seen between the Hispanic and African American students culturally, their perceived value structures, and observable behaviors. A key insight from this research was being a racial/ethnic minority does not per se lead to disproportionate representation in the emotional disturbance eligibility, the dominant culture of the social composition of the student population influences the perceptions and understanding of the educators and professionals who, for the most part, are Caucasian, middle class and more often than not female. Basically, there is an acclimatization of the educators to the culture, behaviors and values of the dominant group against which other racial/ethnic behaviors and values are positioned and judged. The culture, values and behaviors of, in this case, Hispanics students were perceived to be different than that of the African American student and less tolerated. The intent of this researcher was to provide data that advanced the knowledge of how the social environment of a district interplays with its? professionals? belief to shape decision-making and how, in turn, this impacted the issue of overrepresentation of African American students in special education, specifically emotionally disturbed. This study has shown primary contributors to referral and eligibility was poor school leadership over intervention implementation and differences between the social norms and cultural perspectives of the school environment stakeholders and those of African American students. It is critical from both scholarly and applied practice perspectives that an ongoing effort to implement culturally responsive pedagogy within the school environment. Similarly, research focusing on interventions designed to shape teachers? perceptions of student behavior is essential to ensure not only equitable educational opportunities, but also eradicate disproportionality.

The purpose of this quantitative correlational research study was to examine the extent that teaching experience affected the knowledge, implementation, and perceived skill level in implementing the 27 evidence-based practices (EBPs) established by the National Professional Development Center for Autism Spectrum Disorder. The study was conducted in the state of Iowa, with special education teachers from fourteen different school districts. Survey responses were gathered from 228 special education teachers. Of the 228, there were 48 novice teachers and 180 veteran teachers. Novice teachers were classified as having less than three years of teaching experience and veteran teachers with more than three years. Based on the data, results showed that as experience tended to increase from less than three years of experience to more than three years, the scores on EBPs knowledge, implementation, and perceived skills also tended to increase. The results of the study found a positive correlation (r = .26, p = .001) between years of teaching experience and knowledge of EBPs, a positive correlation (r = .22, p = .001) between years of experience and EBP implementation, and a positive correlation (r = .26, p = .002) between years of experience and perceived skill level in implementation. This small effect size indicates that as experience increased, there was a positively correlated increase of teacher knowledge and implementation of the EBPs to use when working with students with autism.

The purpose of this eleventh grade Advanced Placement (AP) program study was to determine factors associated with AP placement and subsequent student performance. This research was considered to be a mixed methods case study with elements of arrested action research. One hundred and twenty-four students, four guidance counselors, three AP teachers, and one administrator provided information used to determine if a problem existed in terms of the influx of students into the AP program without a comprehensive set of research-based supports designed to assist struggling students. Student data included instrument measures, structured written response questions, and secondary source information which was obtained from 124 eleventh grade students in 11 different AP classes between these two comprehensive high-schools in this district. Secondary source data was used to gauge academic ability and preparedness which included collecting: Preliminary Standardized Achievement Test (PSAT) scores, cumulative Grade Point Averages (GPAs), AP final class grades, and AP exam scores. All 124 students also completed three self-report measures designed to gauge test anxiety, academic locus of control, and executive functioning. These students also wrote brief responses to five structured written response questions that were aligned to the self-report measures. Four counselors, three AP teachers, and one administrator were interviewed to better understand their views concerning current AP placement practices and strategies used to support academically at-risk and traditionally underserved students. The analyzed data was then used to create a Professional Development (PD) Module inclusive of feasible and low-cost strategies to improve AP grades and exam scores. This PD Module was subsequently implemented for a short duration in three AP classrooms as the first cycle in an action research project. The three AP teachers were then interviewed in order to garner feedback and ideas on how to improve this PD Module.

Keywords: Advanced Placement (AP), Preliminary Standardized Achievement Test (PSAT), cumulative Grade Point Average (GPA), test-anxiety, academic locus of control, executive functioning, case study, arrested action research, mixed methods, Professional Development (PD)