Measuring economic segregation in the US-Metropolitan areas

Master in Economics: Empirical Applications and Policies. Academic Year 2020-2021This paper aims to provide empirical evidence on “Income Ethnical Segregation” by constructing an index that analyses US Census Data from 1990 until 2010. Following the groundwork of the “SSI” the results can be considered as decomposable and thus also subgroup consistent. The evidence for the biggest 10 MA shows a clear increase of segregation and inequality even though average income climbs as well throughout the years. Same implies that significant differences amongst races have been observed that were especially revealed for the poorer MA such as Los Angeles-Long Beach, CA. As the “Income Ethnical Segregation” can be seen as one component of the overall score of the Entropy Index, which consists of the “Within – Inequality part” and the “Between – Segregation part”, it goes hand in hand with previous assumptions that a higher segregation also estimates higher inequality. The reader will not only be guided through the various indicators and empirical evidence for the case, but moreover also learn about practical application of previously established indices based on the Theil-Between Index. Thus, the main takeaway will be an understanding of the scientific requirements and its empirical application additional to the real analysis on US-Microdata timeseries, when working with segregation measures that include the problematic and continuous variable that is “Income”

Significant speedup of database searches with HMMs by search space reduction with PSSM family models

Motivation: Profile hidden Markov models (pHMMs) are currently the most popular modeling concept for protein families. They provide sensitive family descriptors, and sequence database searching with pHMMs has become a standard task in today's genome annotation pipelines. On the downside, searching with pHMMs is computationally expensive

Efficient implementation of lazy suffix trees

Giegerich R, Kurtz S, Stoye J. Efficient implementation of lazy suffix trees. SOFTWARE-PRACTICE & EXPERIENCE. 2003;33(11):1035-1049.We present an efficient implementation of a write-only top-down construction for suffix trees. Our implementation is based on a new, space-efficient representation of suffix trees that requires only 12 bytes per input character in the worst case, and 8.5 bytes per input character on average for a collection of files of different type. We show how to efficiently implement the lazy evaluation of suffix trees such that a subtree is evaluated only when it is traversed for the first time. Our experiments show that for the problem of searching many exact patterns in a fixed input string, the lazy top-down construction is often faster and more space efficient than other methods. Copyright (C) 2003 John Wiley Sons, Ltd

An Integrative Model of the Personal Selling Process

H. Robert Dodge is Professor of Marketing in the Williamson School of Business Administration at Youngstown State University. David L. Kurtz is the R.A. and Vivian Young Chair of Business Administration and Head, Department of Marketing at the University or Arkansas

Efficient computation of absent words in genomic sequences

Herold J, Kurtz S, Giegerich R. Efficient computation of absent words in genomic sequences. BMC Bioinformatics. 2008;9(1): 167.Background: Analysis of sequence composition is a routine task in genome research. Organisms are characterized by their base composition, dinucleotide relative abundance, codon usage, and so on. Unique subsequences are markers of special interest in genome comparison, expression profiling, and genetic engineering. Relative to a random sequence of the same length, unique subsequences are overrepresented in real genomes. Shortest words absent from a genome have been addressed in two recent studies. Results: We describe a new algorithm and software for the computation of absent words. It is more efficient than previous algorithms and easier to use. It directly computes unwords without the need to specify a length estimate. Moreover, it avoids the space requirements of index structures such as suffix trees and suffix arrays. Our implementation is available as an open source package. We compute unwords of human and mouse as well as some other organisms, covering a genome size range from 109 down to 105 bp. Conclusion: The new algorithm computes absent words for the human genome in 10 minutes on standard hardware, using only 2.5 Mb of space. This enables us to perform this type of analysis not only for the largest genomes available so far, but also for the emerging pan- and meta-genome data

BackPack Food Programs Linked to Higher Test Scores for School Children

Nationwide, over half a million children live in households that report very low food security among children, meaning a child is not eating enough, going hungry, skipping a meal, or not eating for a full day because the household can’t afford food. School meals cannot alleviate this need outside of school hours. To mitigate food insecurity on days when free school meals are unavailable, foodbanks have partnered with schools to create weekend feeding, or “BackPack,” programs that provide children with a bag of nonperishable food to nourish them over the weekend. In this brief, authors Michael Kurtz, Karen Conway, and Robert Mohr summarize their recently published article at the Economics of Education Review, which aimed to understand how these BackPack programs relate to academic success. This research uses data from Northwestern North Carolina tracking the first adoptions and subsequent rapid growth of the BackPack program across schools there. The authors combine participation data with restricted administrative student and school data, which allow them to observe how economically disadvantaged students in schools with and without such programs performed on end-of-grade tests in reading and mathematics. Results provide strong evidence that the introduction of the BackPack program resulted in increased end-of-grade test scores for economically disadvantaged primary school students. The impacts on both reading and math appear strongest for the youngest and lowest performing students

The Implementation of Bankruptcy Code Section 707(b): The Law and the Reality

The introduction of section 707(b) to the bankruptcy code has raised many difficult interpretational issues. This article focuses on those issues concerning the implementation of section 707(b). Under the law, only the courts and the U.S. Trustees are permitted to raise the issue of substantial abuse. Therefore, to determine how section 707(b) is actually being administered, a survey was distributed to the U.S. Bankruptcy Courts and the U.S. Trustees. The results of the survey are integrated into a discussion of the current status of the law and presented in this article. This analysis identifies serious shortcomings with the law that can only be remedied through congressional action. The article concludes with a proposal for solving the problems created by section 707(b)

A Gas Chromatograph-Pedestal Olfactometer (GC-PO) for the Study of Odor Mixtures

Gas chromatography - Olfactometry (GC-O) purifies odorants and delivers them as 1 to 2 second doses to an olfactometer where their odor properties (quale and intensity) can be studied independent of other odors. Adding an odor to the olfactometer air before combining it with the GC effluent creates an odor pedestal upon which an odorant eluting from the GC can be studied to provide insight into mixture perception. This paper describes the development and testing of a gas chromatography - pedestal olfactometer (GC-PO) that produces a Gaussian shaped distribution of one odorant in a background of constant odor composition (the pedestal). A constant pedestal composition was generated by a dynamic headspace released from poly(ethylene) glycol (PEG) solutions into the humidified air of a gas chromatograph-olfactometer (GCO). A magnetic stirrer kept the solvent at the interface in equilibrium with the remainder of the solution producing a constant (+ 10%) pedestal concentration. The resulting pedestal was then combined with a GC effluent and sent to the sniff port of the GC-O. Hexanal, octanal and decanal were analyzed by gas chromatography-mass spectrometry to test the performance and stability of the pedestal. Volatile concentrations of compounds released in the pedestal of GC-PO were linear, constant and could be turned on and off without any detectable background or residual odo