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Exclusionary Zoning and Fiscal Health: An Analysis of Municipal Bonds
Get PDFThis thesis explores the intersection between finance and public policy in municipalities. The factor of interest is restrictive zoning and considering whether communities with more restrictive zoning practices will lead to worsened municipal bond market outcomes. The negative consequences and history of exclusionary zoning are provided, as well as a brief overview of the municipal bond market and outcome variables. The analysis is then conducted on county-level data that has average community-level restrictiveness via the Wharton Residential Land Use Regulatory Index (WRLURI) as well as demographic controls as independent variables, and bond market outcomes as dependent variables. The analysis found that in models with fewer inputs, the WRLURI has a significant negative relationship on municipal bond yield and credit enhancement, but as additional factors were added this significance faded. For bond ratings, the analysis found no significance. This provides some descriptive evidence that exclusionary zoning could contribute to lower levels of risk in municipal finance but is inconclusive and the relationships weaken with added controls
Collation Model for Ms. Codex 1134: [Instructions to Nicolaus Theupulo]
Get PDFInstructions to Nicolaus Theupulo on his appointment by the Doge of Venice to govern Brescia for one year. At this time, Brescia had been under Venetian control for a century, but had experienced recent hostilities with the French; as such, the instructions mention events and governmental decisions from the 15th and early 16th centuries, as well as setting out specific guidelines for Theupulo\u27s tenure in Brescia. Instructions are followed by a table of contents, listing the 76 parts of the instructions (each paragraph is numbered in the text). Notarized by Petrus Grafoldarius. Written in Venice, Italy (f. 2r), in 1525 (f. 29v).https://repository.upenn.edu/sims_models/1099/thumbnail.jp
Topic- and Stance-based Style Shift of North Korean Speakers Living in South Korea
Get PDFWe investigate to what extent North Korean refugee (NK) speakers shift their stop production across topic and stance in conversational speech. The twenty-two NK speakers (F:16, M:6) were engaged in a sociolinguistic interview. A total of 5042 stops were identified and analyzed for VOT and F0 in the following vowel. Stops in the sociolinguistic interview data were coded for topic-stance: contingent upon the topic, North (NK) or South Korean (SK) related topics, they responded with a positive, negative, or neutral stance. Based on previous findings, we predicted that NK speakers would produce more SK-like stops when speaking about South Korea with a positive stance (Nycz 2018). Results of mixed-effects models showed that the NK speakers produced more SK-like stops in terms of VOT when talking about NK and SK topics with emotional stance (negative and positive). This is inconsistent with the idea that speaking about the second dialect region with a positive stance typically results in more second dialect-like speech (Nycz 2018). Unlike the VOT results, the NK F0 patterns were consistent across topic-stance. We interpreted that the consistent F0 patterns might be due to prosodic mitigation (Idemaru et al. 2019, Hübscher et al. 2017). Given that speakers tend not to fluctuate F0 in polite speech, the NK speakers might also try to speak more politely because the NK speakers communicated with an unfamiliar SK interviewer (the first author), using honorific speech forms. Taken together, the findings show NK speakers\u27 mixed pattern of stop productions across topic-stance. Effects of interlocutor and speech address form can be examined in order to further shed light on the complex pattern in a future study
Geometry And Topology: Building Machine Learning Surrogate Models With Graphic Statics Method
Get PDFThis dissertation aims at developing a machine learning workflow in solving design-related problems, taking a data-driven structural design method with topological data using graphic statics as an example. It shows the advantages of building machine learning surrogate models for learning the design topology -- the relationship of design elements. It reveals a future tendency of the coexistence of the human designer and the machine, in which the machine learns the appearance and correlation between design data, while the human supervises the learning process.
Theoretically, with the commencement of the age of Big Data and Artificial Intelligence, the usage of machine learning in solving design problems is widely applied. The existing research mainly focuses on the machine learning of the geometric data, however, the internal logic of a design is represented as the topology, which describes the relationship between each design element. The topology can not be easily represented for the human designer to understand, however it\u27s readable and understandable by the machine, which suggests a method of using machine learning techniques to learn the intrinsic logic of a design as the topology.
Technically, we propose to use machine learning as a framework and graphic statics as a supporting method to provide training data, suggesting a new design methodology by the machine learning of the topology. Different from previous geometry-based design, in which only the design geometry is presented and considered, in this new topology-based design, the human designer employs the machine and provides training materials showing the topology of a design to train the machine. The machine finds the design rules related to the topology and applies the trained machine learning models to generate new design cases as both the geometry and the topology
Statistical Approaches To Reducing Bias And Improving Variance Estimation In The Presence Of Covariate And Outcome Measurement Error
Get PDFLarge epidemiologic studies with self-reported or routinely collected electronic health records (EHR) data are frequently being used as cost-effective ways to conduct clinical research, but these types of data are often prone to measurement error. While large epidemiologic studies play a crucial role in understanding the relationship between risk factors and health outcomes, such as disease incidence, these relationships cannot be properly understood unless methods are developed that reduce the bias caused by errors in both exposure variables and time-to-event outcome variables. Furthermore, variance estimates for outcome model regression parameters can be quite large in the presence of complex error-prone exposures and outcomes, yet strategies to improve variance estimation have been given little attention in the measurement error literature. Throughout this dissertation, we address these gaps in the literature by developing methodology that focuses on (1) reducing the bias that occurs from both error-prone exposures and outcomes in large epidemiologic cohort studies with periodic follow-up, (2) improving statistical efficiency by leveraging error-prone, auxiliary data alongside validated outcome data, and (3) considering alternative, better-behaved variance estimation strategies that may be used when techniques for adjusting for measurement error are applied. In Chapter 2, we present a method that combines an approach for addressing errors in event classification variables with regression calibration, a popular technique for addressing exposure error. This method reduces the bias induced by measurement errors in a discrete time-to-event setting. We apply our method to data from the Women’s Health Initiative (WHI) study to evaluate the association between dietary energy and protein and incident diabetes. Chapter 3 develops an approach for incorporating error-prone, auxiliary data into the analysis of an interval-censored time-to-event outcome. Here, the key goal is to improve statistical efficiency in the estimation of exposure-disease associations. We extend our methodology to handle data from a complex survey design and to be used in conjunction with regression calibration. Using this approach, we assess the association between energy and protein and the risk of diabetes in our motivating study, the Hispanic Community Health Study/Study of Latinos (HCHS/SOL). In Chapter 4, we propose a sandwich variance estimator as an approach for accounting for the uncertainty added by using an estimated exposure when regression calibration is applied to adjust for covariate error. This variance approach broadly applies to other two-stage regression settings. We outline a procedure for easily computing the sandwich in standard software and assess its properties through a numerical study and through illustrative data examples from the WHI and HCHS/SOL studies. Our results show that this method may have advantages over commonly applied, resampling-based variance estimation approaches
Grappling With Hercules: Masculinity And The Male Body In Rubens\u27s Time
No full textThe Flemish artist Peter Paul Rubens (1577-1640) is best known today for his depictions of full-figured women. However, the male nude is just as prevalent in his oeuvre. In fact, muscular male figures were a signature of Rubens’s early career. This dissertation investigates how Rubens and his wealthy, educated peers looked at men’s bodies, including contemporary men in portraiture; idealized male figures (such as Christ and Hercules) in religious and mythological artworks; and male nudes in preparatory drawings and finished paintings. Each chapter explores themes of masculinity, identity formation, and men’s reception of the male form. By examining Netherlandish visual and material culture, this project demonstrates how concepts of ideal masculinity shaped men’s images of themselves and others in the sixteenth and seventeenth centuries. To reflect the range of elite male roles in early modern Antwerp, this project provides studies of Rubens and his friend and patron Nicolaas Rockox (1560-1640). While serving as a court artist and diplomat, Rubens studied and designed idealized male nudes. By marrying twice and fathering eight children, Rubens embraced the role of pater familias, becoming the head of the household that society prescribed. During his time as a city official, Rockox commissioned paintings of powerful male figures that decorated his home and local churches. Widowed and childless, Rockox became a father figure for the city of Antwerp, dedicating himself to the welfare of his hometown and investing in public art, fortifications, and charity. Like so many gentlemen in their circle, Rubens and Rockox modeled their virtuous masculine behavior after biblical, mythological, philosophical, and decorous exemplars. Through the analysis of two specific men’s lives, portraits, and artworks featuring male bodies, this dissertation offers a cultural and historical study of seventeenth-century gender norms that Rubens and his peers inherited, confronted, and, ultimately, reinforced. Analyzing Rubens and his work in the context of idealized and temporal concepts of early modern masculinity provides new insights on the multifaceted identity of one of the most well-studied European painters in art history
Synthesis And Reactivity Of Dicobalt And Diiron Complexes Supported By Binucleating Ligand Scaffolds
No full textHomogeneous complexes have long been used to model and understand both biological and heterogeneous systems. Binucleating ligand scaffolds incorporating more complex design principles that may more accurately represent these phenomena have had a recent resurgence. In this dissertation we discuss the use of two binucleating ligand frameworks that support dicobalt and diiron complexes. The first system, a bis-pyridyldiimine (3PDI2) macrocyclic ligand was used to support a variety of redox-related dicobalt complexes that showed a propensity for strong bond activations on small molecules. The products of these bond activations often had unique binding modes, which may be used to engender future interesting reactivity. In chapter 2, we discuss the C-C bond cleavage of acetonitrile by a dicobalt macrocycle under reducing conditions. The isolated μ-CN and μ-CH3 represent unusual structures in their respective classes. The cyanide features a rare, bent binding mode due to the ligand-imposed constraints and the methyl is the first crystallographically characterized dicobalt μ-CH3 reported, to our knowledge. Oxidation and dimerization of the μ-CN complex lead to two different CN binding modes, highlighting the versatility of the ligand scaffold. In chapter 3, a reduced variant of the dicobalt complex can activate a wide variety of substrates: from H2 and CO2 to N2O and tellurium. The products of these substrate activations were characterized and discussed in context of their binding modes and the ability of the redox active ligand to facilitate the initial reactivity. In chapter 4, a tren-based ligand underwent a C–H activation under reducing conditions to yield a stacked diiron complex. This complex and its one-electron oxidized congener were studied by X-ray crystallography, NMR, IR, UV-vis, Mössbauer, and computationally. Finally, S atom insertion into the Fe–Fe bond was explored. Through redox activity or hemi-liability, both ligand scaffolds helped facilitate reactivity for these potent bimetallic complexes
Bidirectional Relationship Between Opioids And Disrupted Sleep
No full textThe opioid epidemic has generated massive societal, economic, and medical consequences over the last 20 years. Opioids, like most drugs of abuse disrupt sleep, and conversely, poor sleep can be a risk factor for opioid use. However, the precise nature of the relationship between opioids and disrupted sleep is not well known. The research presented here serves to further our knowledge of the neurobiological underpinnings of this pathophysiological feedback cycle between opioids and disrupted sleep. First, we model chronic short sleep in mice and use innovative open-source tools to noninvasively and automatically generate data relating to sleep and morphine reward. We then use electroencephalography to show that morphine disrupts sleep during the dark cycle (active period) after 11 days of morphine. We then look to Mu Opioid Receptors (MORs) in the Paraventricular Nucleus of the Thalamus (PVT) as the locus of morphine-induced sleep disturbance. Manipulating PVT MOR expressing neurons transiently blocked morphine-induced wakefulness in the drug group but not general wakefulness in controls. Finally, using the same morphine administration paradigm, we examine the negative affect associated with protracted withdrawal from morphine. We find that the major cellular energy sensor in the brain, Adenosine Monophosphate-Activated Protein Kinase (AMPK) mediates certain behaviors during protracted withdrawal from morphine. This body of work contributes to our understanding of the intersection between sleep and opioids and demonstrates the importance of considering sleep in the treatment of substance use disorders
Geometry Of Gradient Flows For Analytic Combinatorics
Get PDFAnalytic combinatorics in several variables (ACSV) analyzes the asymptotic growth of generating function coefficients in a direction r. It uses Morse theory on the pole variety V := {H = 0} ⊆ (C∗)d to deform the torus T in the multivariate Cauchy Integral Formula via the downward gradient flow for the log-linear function h = hr = − ∑ rj log |zj|, giving a homology decomposition of T into cycles around critical points of h on V . The deformation can flow to infinity at finite height when the height function is not a proper map. This happens only in the presence of a critical point at infinity (CPAI): a sequence of points on V approaching a point at infinity, and such that log-normals to V converge projectively to r. The CPAI is called heighted if the height function also converges to a finite value. The central questions that I have attempted to answer involve analyzing whether all CPAI are heighted, and in which directions CPAI can occur. I attempted to answer these questions by examining sequences converging to faces of the toric compactification defined by a multiple of the Newton polytope P of the polynomial H. The idea is to show that any projective limit of log-normals of a sequence converging to a face F must be parallel to F. This turns out to be true but only under further hypotheses. It implies that CPAI must always be heighted and can only occur in directions parallel to some face of P. The extra hypotheses hold in smooth cases under generically satisfied conditions. In addition, I show under a smoothness condition, that a point in a codimension-1 face F can only be a CPAI for directions parallel to F, and that the directions for a codimension-2 face can be a larger set, which can be computed explicitly and still has positive codimension. The question of whether non-heighted CPAI exist in general is left open; I conjecture that they do not exist
Essays On Machine Learning And Labor Economics
Get PDFObserved worker and firm characteristics only explain a small wage variation. Beyond characteristics that are directly observed from the data, my thesis develops new empirical methods aimed at identifying unobserved heterogeneity in the labor market.
Chapter 1 proposes an empirical method to measure the effects of coworkers on wages. I take advantage of the recent cutting-edge clustering method that combines machine-learning and economic theory to identify groups of workers with similar latent productivity type. I further apply the cluster-based method to identify the effects of coworkers on wages and evaluate their economic implications in empirical-relevant simulations. The proposed method has proven potential to be applied to the real-world data to improve our ability to understand the role of coworkers in substantive questions where existing methods have limitations