Accelerating Nearest Neighbor Search on Manycore Systems

We develop methods for accelerating metric similarity search that are effective on modern hardware. Our algorithms factor into easily parallelizable components, making them simple to deploy and efficient on multicore CPUs and GPUs. Despite the simple structure of our algorithms, their search performance is provably sublinear in the size of the database, with a factor dependent only on its intrinsic dimensionality. We demonstrate that our methods provide substantial speedups on a range of datasets and hardware platforms. In particular, we present results on a 48-core server machine, on graphics hardware, and on a multicore desktop

Density and temperature of energetic electrons in the Earth's magnetotail derived from high-latitude GPS observations during the declining phase of the solar cycle

Single relativistic-Maxwellian fits are made to high-latitude GPS-satellite observations of energetic electrons for the period January 2006-November 2010; a constellation of 12 GPS space vehicles provides the observations. The derived fit parameters (for energies similar to 0.1-1.0 MeV), in combination with field-line mapping on the nightside of the magnetosphere, provide a survey of the energetic electron density and temperature distribution in the magnetotail between McIlwain L-values of L = 6 and L = 22. Analysis reveals the characteristics of the density-temperature distribution of energetic electrons and its variation as a function of solar wind speed and the Kp index. The density-temperature characteristics of the magnetotail energetic electrons are very similar to those found in the outer electron radiation belt as measured at geosynchronous orbit. The energetic electron density in the magnetotail is much greater during increased geomagnetic activity and during fast solar wind. The total electron density in the magnetotail is found to be strongly correlated with solar wind speed and is at least a factor of two greater for high-speed solar wind (V-SW = 500-1000 km s(-1)) compared to low-speed solar wind (V-SW = 100-400 km s(-1)). These results have important implications for understanding (a) how the solar wind may modulate entry into the magnetosphere during fast and slow solar wind, and (b) if the magnetotail is a source or a sink for the outer electron radiation belt

THE IMPACT OF THE USE OF PROFICIENCY-BASED RUBRICS ON STUDENT GRADING

The purpose of this study is to determine impact of the proficiency-based rubric on student learning, the teacher’s ability to provide consistency in student grading, and communication to parents regarding the child’s academic achievement in kindergarten, first and second grade in one Local Education Agency (LEA) in eastern North Carolina. Based on literature review, proficiency-based rubrics are an effective tool for teachers to use to help promote clarity and consistency in grading. Marzano (2000), Brookhart (2009), Guskey and Bailey (2001), and O’Connor (2002) are just a few of the researchers that provided examples of how rubrics assist teachers in effectively measuring student achievement. Therefore, this research study examined whether proficiency-based rubrics were effective in: (1) producing consistency in grading, (2) equipping teachers with a tool to convey to parents their child’s proficiency and (3) producing a positive impact on student achievement. The data used for this research study were collected from one LEA in eastern North Carolina. Teacher and principal perception as to the impact of the use of the proficiency-based rubric was collected through survey and focus group interviews. To answer the research questions, data were analyzed from surveys and focus group interviews given to both principals and teachers within the Pitt County School District. In order to provide findings regarding the research questions, survey and interview questions were categorized under the classifications of impact, consistency or communication. The data from the surveys and focus group interviews were triangulated in order to effectively summarize the data that were collected. The data from K-2 principals and teachers revealed that both participant groups perceived the proficiency-based rubrics had a positive impact on student grading. However, the data revealed a higher percentage of principals believed the use of the rubrics a more positive effect on student grading as compared to teachers’ beliefs. Based on the findings, consistent grading policies and procedures need to be established by the district as well as continuous professional development for principals and teachers. Additionally, teacher and principal preparation programs need to ensure pre-service candidates are exposed to, and know the value of proficiency-based rubrics on student learning

Enshrining policy in a state’s constitution means that it is more likely to be rewritten as the makeup of the state legislature changes.

Just as the US has a founding document – The Constitution – the states themselves have their own constitutions. But what influences how and when these documents are altered? In new research, Adam Cayton compares the partisan makeup of state legislatures in every year since 1834 to the year in which a state’s constitution was enacted to see when they are replaced. He finds that a state’s constitution is more likely to be replaced when the constitution includes a large amount of policy content and the composition of the legislature has changed

Conflict on the Michigan Frontier: Yankee and Borderland Cultures, 1815–1840

Review of: "Conflict on the Michigan Frontier: Yankee and Borderland Cultures 1815–1840," James Z. Schwartz

Brahma and the Problem of Popularity

Brahma, the creator, theoretically occupies a major position in Hinduism, but receives virtually no bhakti worship. The study examines potential causes of Brahma’s lack of worship through analysis of scholarship, supplemented by interviews with eight Hindus. The subjects were asked to give their own explanations and evaluate scholarly theories on Brahma’s unpopularity. Scholar Km. Rajani Mishra states that after creation, Brahma has nothing to offer humanity, and argues that Brahma’s character was not compelling enough to retain followers. Greg Bailey suggests that Brahma’s role as creator ties him to pravṛttidharma, a worldly mindset that prevents him from granting salvation. Interviews indicated that Brahma is well respected, and the primary cause of his unpopularity remains unclear. Some saw him as subservient to other gods and thus undeserving of worship. Others stated, like Mishra, that Brahma has nothing to offer Hindus after creation. Bailey’s theory of pravṛttidharma was controversial, with some arguing that bhakti deities are based on tradition and not considerations of pravṛttidharma. Most subjects agreed that Brahma once possessed followers. Some argued Brahma was subject to slander and his appealing characteristics were absorbed by other gods. Others speculated a historical disaster may have caused the cult’s deterioration. Still others argued that Brahma never had a widespread following. When combined with existing scholarship, the interviews suggest that unknown historical factors, along with Brahma’s position in mythology, resulted in his cult’s decline, but indicate that Brahma still enjoys respect among Hindus

Evaluating the Performance of in Silico Predictive Models on Detecting Splice-altering Variants

As with any complex biological pathway, the splicing process has both advantages and obstacles with respect to the diversity and fidelity of protein production. The potential benefits of being able to produce multiple versions of a gene (isoforms) must be weighed against the additional complexity introduced by the noisy and mechanistically complicated process of splicing. Indeed, research has found that errors in splicing can be implicated in an increasing number of disorders. Variants that cause disease may operate by disrupting splicing; however many of the variants are frequently annotated as disrupting function through a missense mutation, or via an unknown mechanism. The objective of this study is to determine the ubiquity of splice-altering variants (SAVs) in the human genome with a focus on coding missense and silent synonymous polymorphisms that may impact splicing. As a first step, we evaluated the ability of in silico prediction tools to predict whether a given variant will disrupt splicing. Top performing tools were then used to predict splicing disruption for two sets of variants in the genome; one data set contained variants located anywhere in an exon, and the second restricted variants by location with the focus specifically on those annotated as being involved in disease. The results demonstrate that for some of these prediction tools there is a bias in the results based on variant proximity to the exon-intron junction. Also, analysis of the data sets suggests that the variants listed as non-splice affecting in the database include a considerable number of false negatives. These results may be beneficial for updating the information in widely used databases to improve the usefulness of such resources. The efforts summarized in this thesis will hopefully bring insights into the mechanisms by which splicing errors contribute to disease development and thus facilitate disease treatment improvements

Brahma and the Problem of Popularity

Brahma, the creator god, theoretically occupies a major position in Hinduism but, in practice, receives virtually no bhakti-style devotional worship. The study examines potential causes of Brahma’s lack of popular worship through analysis of existing scholarship, and through in-depth interviews with eight Hindus. These subjects were asked to give their own explanations and evaluate scholarly theories on Brahma’s unpopularity in devotional worship. Among scholarly theories, Km. Rajani Mishra\u27s states that after creation, Brahma has nothing to offer humanity, and argues that Brahma’s character was not compelling enough to retain followers. Alternatively, Greg Bailey suggests that Brahma’s role as creator ties him to pravṛttidharma, a worldly mindset that prevents him from granting salvation. The subject interviews indicate that Brahma is well respected, and the primary cause of his unpopularity remains unclear. Some saw him as subservient to other gods and thus undeserving of worship. Others stated, like Mishra, that Brahma has nothing to offer Hindus after creation. Bailey’s theory of pravṛttidharma was controversial, with some arguing that bhakti deities are based on tradition and not considerations of pravṛttidharma. Most subjects agreed that Brahma once possessed more followers. Some argued Brahma was subject to slander and his appealing characteristics were absorbed by other gods. Others speculated a historical disaster may have caused the cult’s deterioration. Still others argued that Brahma never had a widespread following. When combined with existing scholarship, the interviews suggest that unknown historical factors, along with Brahma’s position in mythology, resulted in his cult’s decline, but indicate that Brahma still enjoys considerable respect among most Hindus

Legislators flip-flop on passing a bill when they think voters want them to, but only when it’s visible

People often perceive politicians as being both inconsistent and uncompromising despite the fact that these perceptions cannot both be true. In reality, legislators have to walk a fine line between responsiveness and consistency to remain in good standing with both their party and their voters. In new research, Adam Cayton studies how and when legislators do change their positions on issues. He finds that members of Congress change positions on very visible final passage votes in response to their districts, but not on poorly understood procedural votes

Time-varying conditional Johnson SU density in value-at-risk (VaR) methodology

Stylized facts on financial time series data are the volatility of returns that follow non-normal conditions such as leverage effects and heavier tails leading returns to have heavier magnitudes of extreme losses. Value-at-risk is a standard method of forecasting possible future losses in investments. A procedure of estimating value-at-risk using time-varying conditional Johnson SU¬ distribution is introduced and assessed with econometric models. The Johnson distribution offers the ability to model higher parameters with time-varying structure using maximum likelihood estimation techniques. Two procedures of modeling with the Johnson distribution are introduced: joint estimation of the volatility and two-step procedure where estimation of the volatility is separate from the estimation of higher parameters. The procedures were demonstrated on Philippine-foreign exchange rates and the Philippine stock exchange index. They were assessed with forecast evaluation measures with comparison to different value-at-risk methodologies. The research opens up modeling procedures where manipulation of higher parameters can be integrated in the value-at-risk methodology.Time Varying Parameters; GARCH models; Nonnormal distributions; Risk Management