Real-World Contexts in Urban High School Mathematics Lessons
Year of Dissertation:
2013
This study analyzes the uses of real-world contexts in mathematics lessons in the classrooms of four teachers across two school years at an urban high school. Drawing upon a framework of culturally relevant mathematics pedagogy, this dissertation focuses on how real-world contexts are connected to teaching mathematics for understanding, centering mathematics instruction on students' experiences and classroom participation, and developing students' critical consciousness. Analysis of real-world contexts in lessons focuses on the extent to which they are adapted from curricular sources and the role that lessons play within the lesson. For those real-world contexts which are at the center of a mathematics lesson, the nature of the mathematical modeling in which students engage is analyzed. Finally, the extent to which students and the teacher participate in the process of elaborating key features of the context whether in terms of experiences, perceptions, or opinions, is also considered. These different categories for real-world contexts are then used to compare three different measures of the lesson. These include the cognitive demand of the main mathematical task, different ratings of the instructional environment, and the distribution of class time in terms of the participation categories offered to students. Results point at the promise of real-world contexts as the basis for motivating metaphors to explore noncontextualized mathematical procedures and concepts, the need to structure lessons so that students can develop models rather than apply given models, and the importance of elaboration in supporting student understanding and participation.
Hash Functions, Latin Squares and Secret Sharing Schemes
Year of Dissertation:
2010
A secret sharing scheme creates an effective method to safeguard a secret by dividing it among several participants. Since the original idea introduced by Shamir and Blakley in 1979, a variety of threshold secret sharing schemes and other types have been suggested by researchers. The first part of this thesis shows how to apply hash functions in secret sharing scheme designs. By using hash functions and the herding hashes technique, we first set up a (t + 1, n) threshold scheme which is perfect and ideal, and then extend it to schemes for any general access structure. The schemes can be further set up as verifiable if necessary. The secret can be quickly recovered due to the fast calculation of the hash function. In particular, secret sharing schemes based on Latin squares will be discussed.
THE EFFECT OF FIRM-SPECIFIC RETURNS VARIATION ON R2: FROM THE PERSPECTIVE OF THE ACCRUAL ANOMALY
Year of Dissertation:
2009
R-square, calculated as CAPM of stock returns regressed on a market index, is constructed to explain stock price change by market-wide information. In my dissertation, I have analyzed the behavior of R-square and its decomposed variations (firm-specific and market-wide variation) with regard to the accrual anomaly, domestically and internationally. My major results in the US are as follows. First, the effect of accrual anomaly significantly lowering future R-square associated with higher firm-specific variations is robust and is not affected by (1) size, firm age, and other control variables; (2) industry risk and market risk; (3) other alternative explanations of accrual anomaly (value-glamour anomaly, bankruptcy risk, and arbitrage risk). Second, earning management is likely to be the reason why R-square decreases the accrual anomaly. Third, the difference in R-square between portfolios of good/poor accrual quality is subject to firm-specific variation. Fourth, the robustness of accrual anomaly significantly lowering future R-square even applies to the industry level. Using equity markets in 31 countries to investigate the relationship between the accrual anomaly and R-square, I find the occurrence of accrual anomaly significantly decreasing R-square is clustered largely in developed countries with relatively low R-square (USA, Australia, UK, Canada, Japan, Germany, Netherlands, South Africa, and France), casting doubt on the statement that the more efficient the capital market is, the lower R-square is. In terms of market efficiency, the actual R-square of developed countries should be higher. Finally, I observe that the phenomenon of accrual anomaly significantly lowering future R-square is more frequently found in countries with a low level of government corruption, those with a common law tradition, those with low quality of accounting standards, and those where shareholder ownership is widely dispersed. In addition, an analysis of ADRs (American Depository Receipts) helps to explain the effect of institutional and governmental structures on the relation between R-square and the accrual anomaly. Last, I also investigate the relation between stock return variation and extreme trading volume in the tail by demonstrating the asymmetry of the return and volume in six emerging countries.
Originality and Complexity: An Analysis of Robert Schumann's Gesänge der Frühe, Op. 133
Year of Dissertation:
2013
Advisor:
L. Poundie Burstein
In October 1853, Schumann wrote a set of five character pieces for piano entitled Gesänge der Frühe. During mid-1853, when Schumann composed this cycle, his creative energy was at its peak, as he exhibited remarkable pace and productivity. Schumann's unswerving enthusiasm for the Gesänge and its publication, which occurred in November 1855 as his Opus 133, is attested by many letters to his confidants during his final years. Perhaps due to the noticeably distinct compositional style of the Gesänge, as well as Schumann's mental illness during his late years that has been a source of much prejudice regarding his late compositions, relatively scant attention in both pedagogical and performing venues has been paid to this last piano cycle of Schumann. A comprehensive analytical study of the five Gesänge helps reveal much of this work's distinct compositional style, which represents both influences from the past and Schumann's personal originality.
Racialized Identities in a Colorblind Context: Filipino American Youth Negotiating Discourses of Race, Identity, and Diversity in School
Year of Dissertation:
2012
This dissertation is an ethnographic study that examines the discursive process by which 1.5 and second generation Filipino American students construct racial and ethnic identities in the context of school. Using a theoretical framework that focuses on the racialization of immigrant students, this study investigates some of the underlying assumptions about race, ethnicity, culture, and diversity that impact the institutional discourses in a large, northeastern high school. It explores the discordance between a context in which race is not supposed to matter and students' experiences with race everyday. Findings suggest that at the institutional level, race is viewed as polarizing, rooted in bias and prejudice, and a threat to community. Thus, discourses are aimed to defuse and downplay race by calling for students and faculty to put racialized differences aside. In contrast, race proved to be a significant factor in youth participants' daily school experiences. They participated in activities bounded and defined by race, and dialogued with their peers about ethnic and racial categorical meanings, which manifested in conversations as cultural stereotypes, yet verged on outright racism. Findings also show how Filipino youth found innovative ways to offer alternative representations to dominant perceptions of culture. Traditional notions of culture and identity as fixed were challenged and instead are shown to emerge as socially-embedded systems of meaning.
Mutual Aid Processes in Treatment Groups for People with Substance Use Disorders: A Survey of Group Practitioners
Year of Dissertation:
2009
There is scant empirical evidence demonstrating the presence and importance of mutual aid processes in Substance Use Disorder (SUD) treatment groups (Crits-Christoph et al, 1999; Sandahl & Ronnberg, 1990). Consequently this exploratory, internet-delivered survey was conducted to further examine the presence of mutual aid processes in abstinence-based SUD treatment groups in the field and the variables that are associated with higher amounts of mutual aid. The sample for this study comprised members of NAADAC, the Association for Addiction Professionals (n=484). In order to obtain information about group treatment in the field a trigger question was asked allowing the identification of respondents that had led a treatment group in an abstinent-based setting within the previous two years (n=369). The study utilized an author-created scale, the Mutual Aid Processes Scale (MAPS) comprised of 30 mutual aid processes. Reliability testing of the MAPS indicated high reliability, with a Chronbach's Alpha of .96. Factor analysis suggested that all 30 items related as a unitary construct.
Dissertation The relationships among custody and visitation arrangements, parental conflict, and adolescent outcomes in the context of divorce
Year of Dissertation:
2013
Experiencing parental divorce during adolescence has been associated with a number of negative adolescent outcomes. A high level of parental conflict has been identified as an important determinant of adolescents' adjustment to their parents' divorce. This study sought to examine the relationships between level of parental conflict, custody and visitation arrangements, and negative adolescent outcomes. This research is based on archival data obtained in the course of a forensic child custody evaluation, and utilized a sample of 89 couples and 196 pre-adolescents and adolescents. Results demonstrated that higher levels of parental conflict were associated with a greater number of negative adolescent outcomes. It was also found that children whose parents had joint custody experienced fewer negative adolescent outcomes than those who were in the sole custody of one parent. These results suggest several important implications for practice, policy, and future research.
MERIT- Mentalization Enhanced Remediation an Integrated Treatment - A Comprehensive Intervention for Children with Autism
Year of Dissertation:
2011
In the treatment of autism two models have evolved that have attempted to integrate aspects from skill based approaches with a more developmental model. These models remain predominantly developmental. Although these more integrated models have taken into consideration the advances that have allowed us to better understand the neuropsychological profiles of children on the spectrum, they do not attempt to intensively remediate many of the areas we know to be compromised.
Pannalal Ghosh and the Bânsurî in the Twentieth Century
Year of Dissertation:
2010
Pannalal Ghosh (1911-1960) is credited with the introduction of the bânsurî (North Indian bamboo flute) into Hindustani classical music in the twentieth century. While the transverse flute played a significant role in the music of India at least since the early centuries CE, it had lost its status as a prominent instrument in Indian art music several hundred years before Ghosh brought it to the forefront of Hindustani classical music. Ghosh's achievement is considered in the context of his time in terms of the social, political, economic, technological, and musical circumstances in India, and particularly Bengal. While twentieth-century developments contributed to his success, it was ultimately through his own efforts that the bânsurî was accepted as a featured Hindustani classical instrument. By redesigning the instrument, working out a technique to emulate the subtleties of the voice, listening to diverse genres and styles of music, engaging in intensive study, and conceptualizing his own eclectic style of playing, he succeeded in convincing twentieth-century audiences that the bânsurî deserved a place as a valued instrument for the performance of Hindustani classical music. His achievement also paved the way for other instruments such as shahnâî, sârangî, and santûr to achieve similar recognition in the classical music of North India.
Physical and chemical factors affecting the distributions of freshwater snails in four lakes in the New Croton/Muscoot watershed Westchester county, NY
Year of Dissertation:
2011
In a model study four lakes were examined to determine if benthic macroinvertebrates in the littoral zone were affected by physicochemical factors and shoreline development. The central hypothesis was that there would be correlations between the physicochemical factors in the lakes, levels of development around the lakes and the populations of benthic organisms. The study was conducted from April through October 2009 and 2010. Diversity and EPT indices were calculated to quantify taxa. Physicochemical variables measured included: temperature, pH, DO, mean nitrate and phosphate concentrations, total hardness, calcium, total dissolved solids (TDS), conductivity (ECS) and coliform testing. Sediment analysis and loss on ignition studies were done to assess percent composition, percent organic matter and percent carbonates in littoral sediments. Data characterizing shoreline development was collected from appropriate town, county and state resources, including: phosphorous loading, number of structures, number of storm drains, percent developed land and run-off into the lakes. Multivariate and correlation analyses were used to explore the data and to identify significant relationships between the benthic fauna and the abiotic variables. Results showed that freshwater benthic macroinvertebrates had significant correlations to physicochemical and development factors, including: ambient temperatures, hardness, DO, ECS, TDS, pH, percent silt, mean nitrate concentrations, coliforms, phosphorous loading, percent developed land, storm drains and the number of structures. The results of this study illustrate how anthropogenic inputs associated with development affect benthic macroinvertebrates in the littoral zone of suburban lakes.