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http://hdl.handle.net/1957/3
OSU Libraries deliver distinctive and outstanding service to the OSU community and the state of Oregon through our support of OSU’s research, instructional, and outreach missions. A dedicated commitment to proven and emerging technologies has enabled us to successfully develop unique collections and services.2014-07-31T03:29:05ZStatistical models for Q-permutations
http://hdl.handle.net/1957/50938
Statistical models for Q-permutations
Silverberg, Arthur R.
A person's preferences for m objects are often expressed as a ranking or permutation of all these m objects. Sometimes just some, say the top q (≤m) objects are listed - this will be called a q-permutation. If people are indifferent to the objects, all permutations have the same probability. This leads to the uniform distribution on permutations. However, people usually have preferences, and they may differ from group to group. Hence, it is necessary to have non-uniform distributions and methods to fit them. Goodness-of-fit tests of such models will be needed. Very few non-uniform distributions have been suggested in the literature. The only test of uniformity deals with full, not partial permutations. This thesis suggests models for q-permutations, goodness-of-fit tests for them including a test for uniformity of q-permutations and a test whether different groups rank similarly. Two new statistical models for q-permutations are introduced. The first model is defined by successive sampling from q vases that may have different proportions of balls labeled l,...,m. A vase is an urn where the number of balls may be infinite. The second is the Log-Linear model. It may be obtained by modifying the sampling scheme on these vases. The sufficient statistics of the Log-Linear models are the numbers of rankers who rank the ith object jth. The likelihood ratio test of the Log-Linear model versus an unrestricted alternative has an asymptotic chi-square distribution whose degrees of freedom are derived here. The Log-Linear model contains the uniform distribution; the likelihood ratio test of the uniform versus the Log-Linear alternative is shown to have (m-l)q degrees of freedom. A hierarchical family of Log-Linear models can be defined that range from the uniform distribution on q-permutations to the full Log-Linear model. This family may be used to test if the object that is ranked ith has a uniform distribution over all m objects. Log-Linear models are fitted to two different datasets. The Log-Linear models seem to fit well and are parsimonious. These data sets have several groups of rankers. Separate Log-Linear models maybe fitted to each group or one model may be fitted to the entire dataset. The formula for asymptotic degrees of freedom for the likelihood ratio test of the separate models versus one common model, are derived. In this way we can test if the rankings of two or more groups are just different samples from the same distribution on q-permutations or are from different distributions. Iterative numerical methods are given for fitting both the vase and Log-Linear models.
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1980-01-01T00:00:00ZOn-chip integration techniques for millimeter-wave CMOS circuits
http://hdl.handle.net/1957/50937
On-chip integration techniques for millimeter-wave CMOS circuits
Islam, Rownak, 1976-
This dissertation focuses on using on-chip fabrication techniques to integrate broadband antennas with transmitter/receiver (Tx/Rx) integrated circuits (ICs) that operate up to 300 GHz. On-chip integration depends on the design of high performance passives and radio frequency (RF) matching networks. This research has demonstrated three types of interconnect performances up to 325 GHz. This is the first demonstration of grounded coplanar waveguide (GCPW) interconnects fabricated on benzocyclobutene (BCB) showing that the loss is comparable to that of microstrip. A comprehensive CPW study in BCB has shown that up to 60 GHz, 24 [micro]m of BCB is sufficient for minimum loss and up to 300 GHz, 60 [micro]m BCB height is required to approach GCPW performances. Post-CMOS passives have been demonstrated to characterize the back-end-of-line (BEOL) dielectric. A transition from a silicon IC to post-CMOS has been demonstrated on a 180 nm TSMC die with a microstrip patch antenna in the 200 GHz range. This research focuses on the complete engineering design cycle (simulation, fabrication and measurement), with special emphasis on process development.
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2013-01-01T00:00:00ZUnder co-construction : parent roles in promoting college access for students of color
http://hdl.handle.net/1957/50933
Under co-construction : parent roles in promoting college access for students of color
Auerbach, Susan, 1956-
Most parents of color now aspire to college for their children, yet students of color remain underrepresented in four-year institutions. With the loss of key institutional supports, the onus of college planning now falls largely on students and their families on an uneven playing field. How do parents of color without college experience construct and enact their role in promoting college access for their children? I examined this question in an ethnographic case study of 16 workingclass Black and Latino parents whose children were in a college access program at a diverse Los Angeles-area high school. Primary data came from two in-depth interviews with each parent and three years of participant observation at the school, supplemented by student interviews from a database. Parents believed that they were providing important support for college but did so in different ways according to their capacity (college knowledge) and inclination (predisposition for proactive support). Coding and analysis for emergent themes revealed three role orientations along a continuum of support: Moral Supporters, who offered encouragement and indirect guidance at home; Struggling Advocates, who provided monitoring at home and advocacy at school despite obstacles; and Ambivalent Companions, who gave emotional support despite ambivalence on college goals. As anticipated, parent roles were found to be fundamentally socially structured by parents' class and race/ethnicity, as well as culturally mediated and psychosocially enacted. Parents co-constructed their roles with others as members of social and cultural groups in particular home and school contexts. I use cultural and social capital theory to explain variation in role construction and theories of cultural models and self-efficacy to explain subtler nuances. Building on Bourdieu's concept of the habitus-what parents see as desirable, appropriate, and possible for "people like us"-I suggest the formula, (Parents' Capacity x Inclination) + Perceptions of/relations with child + Perceptions of/relations with school = Parent Role. With its highlighting of parents' voices and struggles, this study informs policy and practice on parent involvement and college access while contributing to theory and a more inclusive discourse on parents and schooling.
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2001-01-01T00:00:00ZHigh-achieving, low income, first-generation Latino community college students : cultural capital, social capital, self-perceptions, and college choice
http://hdl.handle.net/1957/50930
High-achieving, low income, first-generation Latino community college students : cultural capital, social capital, self-perceptions, and college choice
González, Verónica Ventura
Though an increasing number of Latino students is attending college upon graduation from high school, the vast majority of these students, even if they are high-achieving students who could attend a four-year college or university, choose to enroll into two-year community colleges. This study discusses the process by which high-achieving, low-income, first-generation Latino students make college choices. This study uses McDonough's college choice model and Stanton-Salazar's social capital framework on institutional and protective agents to analyze student interview data to help explain how social class, schooling experiences, families, and student perceptions impact college choices and opportunities for Latino students. The results of this study and previous research suggest educational practices and policies which would improve young Latino's access to four-year colleges.
Access restricted to the OSU Community
2013-01-01T00:00:00Z