VictorJuiz/thesis huggingface dataset:
Assessing Accrual Quality in Financial Institutions

This paper provides a framework for assessing the accrual quality of financial institutions and applies it to commercial banks' loan portfolios. I first develop an accrual reliability categorization for financial institutions and show that existing findings for non-financial firms extend to financial firms. I next demonstrate how supplementing the information in accruals leads to significantly improved assessment of accrual quality. Focusing on commercial banks' loan portfolios, I supplement information in accruals with a measure based on footnote disclosures regarding loan portfolio concentrations and regional economic indicators. I call this measure loan portfolio quality index and show that it further isolates less reliable accruals and significantly improves the forecasting of future earnings and stock returns.

Advisor: Sloan, Richard G
Firespitters: Performance, Power, and Payoff in African American Women's Humor, 1968-Present

This study considers the social, cultural, and political production of black women's humor, making the case that humor becomes more than merely a technique of entertainment. Instead, I argue that humor is a mode of literacy and site of self-authorship for African American women across a variety of discursive fields, including literature, sketch comedy, stand-up comedy, and electoral politics. Usually described as a "routine," the professional stand-up comics of this study are in fact presenting new ways of thinking about race, class, sex, culture, and power. Using archival research, ethnographic interviews, participant observation, and close readings of performances, this dissertation engages several questions: how do black women use humor to express emotions like desire, anger, and contempt? What are the effects of black women's public performances on their own identities? What do their performances tell us about black culture? How do ideas about black womanhood and feminism factor into their dialogue? What personal, political, and economic opportunities does stand-up comedy offer African American comediennes? Finally, how do black women engage in practices of self-fashioning in and through stand-up comedy? A deeper understanding of the affective and political dimensions of black women comedians' practices highlights stand-up comedy as a renegade space in which performers move literally and figuratively from outrageous comics to become audacious thinkers and potent social critics.

Advisor: Taylor, Ula Y
Cavity Optomechanics in the Quantum Regime

An exciting scientific goal, common to many fields of research, is the development of ever-larger physical systems operating in the quantum regime. Relevant to this dissertation is the objective of preparing and observing a mechanical object in its motional quantum ground state. In order to sense the object's zero-point motion, the probe itself must have quantum-limited sensitivity. Cavity optomechanics, the interactions between light and a mechanical object inside an optical cavity, provides an elegant means to achieve the quantum regime. In this dissertation, I provide context to the successful cavity-based optical detection of the quantum-ground-state motion of atoms-based mechanical elements; mechanical elements, consisting of the collective center-of-mass (CM) motion of ultracold atomic ensembles and prepared inside a high-finesse Fabry-P'erot cavity, were dispersively probed with an average intracavity photon number as small as 0.1. I first show that cavity optomechanics emerges from the theory of cavity quantum electrodynamics when one takes into account the CM motion of one or many atoms within the cavity, and provide a simple theoretical framework to model optomechanical interactions. I then outline details regarding the apparatus and the experimental methods employed, highlighting certain fundamental aspects of optical detection along the way. Finally, I describe background information, both theoretical and experimental, to two published results on quantum cavity optomechanics that form the backbone of this dissertation. The first publication shows the observation of zero-point collective motion of several thousand atoms and quantum-limited measurement backaction on that observed motion. The second publication demonstrates that an array of near-ground-state collective atomic oscillators can be simultaneously prepared and probed, and that the motional state of one oscillator can be selectively addressed while preserving the near-zero-point motion of neighboring oscillators.

Advisor: Stamper-Kurn, Dan M.
Program Verification with Property Directed Reachability

As a consequence of the increasing use of software in safety-critical systems and the considerable risk associated with their failure, effective and efficient algorithms for program verification are of high value. Despite extensive research efforts towards better software verification technology and substantial advances in the state-of-the-art, verification of larger and complex software systems must still be considered infeasible and further advances are desirable. In 2011, Property Directed Reachablity (PDR) was proposed as a new algorithm for hardware model checking. PDR outperforms all previously known algorithms for this purpose and has additional favorable algorithmic properties, such as incrementality and parallelizability. In this dissertation, we explore the potential of using PDR for program verification and - as product of this endeavor - present a sound and complete algorithm for intraprocedural verification of programs with static memory allocation that is based on PDR. In the first part, we describe a generalization of the original Boolean PDR algorithm to the theory of quantifier-free formulae over bitvectors (QF\_BV). We implemented the algorithm and present experimental results that show that the generalized algorithm outperforms the original algorithm applied to bit-blasted versions of the used benchmarks. In the second part, we present a program verification frontend that uses loop invariants to construct a model of the program that overapproximates its behavior. If the verification fails using the overapproximation, the QF\_BV PDR algorithm from the first part is used to refine the model of the program. We compare the novel algorithm with other approaches to software verification on the conceptional level and quantitatively using standard competition benchmarks. Finally, we present an extension of the proposed verification framework that uses a previous dynamic approach to program verification to strengthen the discussed static algorithm.

Advisor: Kuehlmann, Andreas
From Contraband Capital to Border City: Matamoros, 1746-1848

This dissertation project describes the developing political and cultural economy of the port of Matamoros, especially focusing on the city's insertion into vibrant trade networks that originated in New Orleans, Louisiana. I approach my study from two different angles: first, through a reconstruction of the economic activity of the city and its trading partners, and second, by surveying the dynamics of political interactions between local players. The city's port was the conduit for a vibrant contraband trade during this period, and my dissertation uses various innovative methods (especially the reconstruction of trade networks) and obscure sources to quantify the degree to which this illicit commerce contributed to the growth of Matamoros and the region more broadly. My work also analyzes the port's legal trading connections to New Orleans and other North American entrepôts as well as to the interior of the Mexican North, west to Monterrey, and north across the Rio Grande to Texas. Finally, I untangle the complex ways that Matamoros' merchants and political elite defended international maritime trade--the lifeblood of the economy--by carefully maneuvering among a multiplicity of state, national, and international actors./nUsing the tools of political economy, my dissertation provides a complex understanding of the relationship between politics and trade in Mexican history, blurring the one-way lines of causation found in much of the current scholarship. Although the primary methods I use are those of political economy, I see cultural exchanges and influences as integral to the developing trade networks. My findings complicate Mexican economic and political historiographies as well as our current understanding of trans--Caribbean trading systems.

Advisor: Chowning, Margaret
Essays on the Industrial Organization of Food Retailing

This thesis consists of two empirical studies of the industrial organization of food retailing./nChapter 1 investigates consumer behavior in response to changes in variety in grocery store offerings. Using a rich panel dataset of consumer purchases from one national retailer, we measure the effects of changes in product variety on sales of ice cream, where the assortment changes were gradually introduced to stores. We use a difference in differences approach to measure treatment effects against trends in stores prior to treatment. Our results show an adjustment to product variety causes consumers to alter their purchasing behavior, at least in the subsequent eight weeks of the change. When the rearrangement consisted of adding additional products, consumers purchased more on average in the immediate term, but sales increases mitigated over time, with smaller magnitude increases in variety experiencing sales reductions in later weeks. Product groups treated with reduced variety experienced decreased sales both in the immediate and longer term. We find that extending and reducing assortment have asymmetric effects, with a marginal change to increased variety boosting sales less than a marginal change in decreased variety. Larger magnitude reductions perform poorly in the short run, but actually perform better than both smaller variety reductions and small variety increases in later weeks./nIn Chapter 2, I investigate the following question: do firms respond to quality disclosure by nearby competitors? This paper utilizes exogenous variation provided by Los Angeles County's introduction of restaurant hygiene grade cards to explore inter-firm responses in markets for differentiated goods. Under this program, a subset of cities adopted mandatory grade card posting, requiring restaurants to disclose hygiene. This study demonstrates that restaurants under a voluntary hygiene disclosure policy improved hygiene more when located closer to restaurants in mandatory disclosure areas. The proximity effect implies that mandatory disclosure policies influenced restaurant hygiene in nearby voluntary disclosure areas, thus providing direct evidence that quality-disclosure regulations affect non-targeted firms.

Advisor: Villas-Boas, Sofia
Perloff, Jeffrey
Setting us straight! The Role of Sleep in Modulating Emotional Reactivity

Folk wisdom has long implied a critical role for sleep in emotional processing, highlighted by sayings as `Sleep on it and you'll feel better in the morning'. However, until very recently there was a lack of objective research investigating this claim. Now rapidly emerging evidence describes a powerful and causal relationship between sleep and affective brain regulation. These findings are mirrored by long-standing clinical observations demonstrating that nearly all mood and anxiety disorders co-occur with one or more abnormalities of sleep. This dissertation aims to (1) set forth a rapid-eye movement (REM) sleep hypothesis of affective brain homeostasis, optimally preparing the organism for next-day social and emotional functioning, (2) provide behavioral evidence of detrimental impairments in emotional functioning following sleep deprivation, and (3) outline affective brain and behavioral benefits of sleep when it is obtained. Finally, the discussion will describe how this model may explain the prevalent relationships observed between sleep and affective disorders, including relevant treatment mechanisms, with a particular focus on post-traumatic stress disorder (PTSD).

Advisor: Walker, Matthew P
Wireless Weigh-In-Motion: using road vibrations to estimate truck weights

Vehicle count and weight data plays an important role in traffic planning, weight enforcement, and pavement condition assessment. This data is primarily obtained through weigh stations and weigh-in-motion stations which are currently very expensive to install and maintain. This dissertation presents a wireless sensor-based solution that is relatively inexpensive, and uses the measured pavement vibrations to estimate weight of moving vehicles./nThe proposed wireless sensor network (WSN) consists of vibration sensors that report pavement acceleration and temperature; vehicle detection sensors that report a vehicle's arrival and departure times; and an access point (AP) that controls the sensors and processes the incoming sensor data. The system can enable many new applications in infrastructure monitoring and intelligent transportation. We present energy-efficient algorithms for three such applications: automatic vehicle classification for categorizing each passing vehicle based on its axle count and inter-axle spacings; weigh-in-motion for estimating individual axle weight and total weight of trucks while they are traveling at normal speeds; and estimating pavement displacement from measured acceleration./nThe wireless vibration sensor developed for this project has a high resolution (≈ 400 μg) and is immune to traffic sounds that are generally picked up by MEMS accelerometers. The prototype system was deployed on real highways and results for vehicle classification, weigh- in-motion, and displacement estimation were compared against reference measurements. The system passed the accuracy standards for weigh-in-motion (WIM) systems and outperformed a nearby commercial WIM station, based on conventional technology. Since sensors are embedded directly in the pavement, the system can also enable real-time monitoring of pavement condition.

Advisor: Varaiya, Pravin
Biomechanics and evolution of flight in stick insects

Many unresolved questions in animal flight evolution relate to the transition between flightless and volant forms. Functional analysis of transitional modes using anatomical intermediates may help to assess the biomechanical underpinnings to such transitional processes. The group of stick insects exhibits tremendous diversity in wing sizes, which is potentially correlated with selection gradient for wing size. This dissertation work uses stick insects as a model system to address the ecological context of controlled aerial behaviors and the evolutionary consequences of flight loss./nChapter 1 explores the behavioral context of controlled aerial descent in the newly hatched larvae of an Australian stick insect Extatosoma tiaratum, which exhibit ephemeral ant-mimicry and hyperactive dispersal activities. Through lab experiments, we documented the ontogenetic variation in various taxic behaviors and voluntary drop as an escaping response. Chapter 2 explores the visual ecology of directed aerial descent in larval E. tiaratum. We investigated how visual contrasts are used as locomotor references during directed aerial descent. Our results suggest the use of vertically constant contrast edges is a major component of directional targeting. The utility of contrast as visual cues was further shown to be dependent on both the heterogeneity of the visual environment and the quality of perceived signals. Chapter 3 addressed the biomechanics of aerial righting behaviors in larval E. tiaratum. Through high--speed filming and three--dimensional motion reconstruction, the results showed highly controlled leg movements are involved in righting maneuvers. Through posture control, the insects achieve effective righting rotation. More subtle leg movements were also shown in stroke--like patterns, which are instantaneously correlated with whole--insect rotation. This study provided useful information for understanding the ecology and evolution of controlled aerial behaviors in invertebrates. Chapter 4 addressed the functional consequences of progressive wing size reduction along an altitudinal gradient in three populations of a stick insect Asceles tanarata native to Malay Peninsula. We investigated how wing and body morphology change along the altitudinal gradient, and further studied the biomechanics of flight in each flight morph. The results indicate the reduction of fight apparatus leads to changes in wing design and wing kinematics. Reduced flapping fight performances resemble parachuting and gliding. Due to both altered kinematics and flight trajectories different from conventionally recognized flapping flight, the aerodynamics of wing flapping is characterized by large advance ratio and reduced half--stroke asymmetries. Although the reduction in flight performance is closely correlated with the reduction of wing size, wing aerodynamics shows more complex pattern along the performance gradient.

Advisor: Dudley, Robert
Wake, David
The Scale Problem: Food Safety, Scale Politics, and Coherence Deficits in China

Why do food safety problems in China continue to emerge at an alarming rate? Central and local government officials are highly incentivized to address food safety, but officials have struggled to develop multilevel governance solutions to address the crisis. Contrary to studies that suggest that poor governance outcomes in China are often due to bureaucratic fragmentation, this dissertation highlights the policy challenges that emerge as a result of a contentious process of integrating a fragmented system of governance. For policy issues that are trans-regional and govern a common market, such as food safety, actors understand policy coordination is essential because regulatory failures in one locality can quickly spread to others. However, despite the felt need for an integrated governance approach, regulators, producers, and civic organizations fiercely contest the means to ensure food safety, leading to regulatory incoherence./nThe dissertation asserts that the inability of actors to develop a system of integrated food safety governance is directly related to a scale problem. First, actors must overcome a structural scale problem in which millions of actors must coordinate regulatory activity in a multilevel, multi-scale context. In addition to spatial (patch to globe) and jurisdictional (village to intergovernmental) scales, governance must be coordinated on network (family to trans-society), knowledge (local knowledge to universal law), and temporal (short to long-term) scales, among others. Policies can be poorly coordinated which creates scale mismatches. For example, long-term national policies may conflict with local short-term initiatives (jurisdictional and temporal mismatch). Mismatches persist due to different actors' political commitments to particular food safety approaches, which leads to contentious scale politics regarding food safety. Second, actors must also address a policy scale problem. A national food safety system requires a large-scale, non-incremental policy solution. However, due to fierce scale politics, China has adopted small-scale, gradualist policies that have only exacerbated regulatory incoherence./nThe study draws from over 170 interviews with food producers and government regulators in nine counties. The dissertation studies community governance food safety solutions in the Community Supported Agriculture market; foreign-controlled farms in the export sector; co-regulatory initiatives through farmers' cooperatives and dragonhead enterprises; and state-led food safety initiatives in the domestic sector.

Advisor: O'Brien, Kevin J
Development of Oxidative Bioconjugation Methodology for the Site-Selective Modification of the Electron Rich Aromatic Amino Acids

As applications of protein-based materials become increasingly complex, there is a growing need for an expanded set of bioconjugation reactions that can attach synthetic components to defined locations on protein substrates. Although the introduction of artificial amino acids is a useful method for achieving site-selective protein modification, there are advantages to targeting native amino acids that can be introduced without specialized expression systems. This work describes the discovery, development, and application of new oxidation-based bioconjugation methods that target the native electron-rich aromatic amino acids, tyrosine and tryptophan. These methods include a peptide modification strategy that uses synthetic reagents to site-selectively introduce and modify oxidized tryptophan residues, as well as series of protein modification strategies that use cerium(IV) ammonium nitrate (CAN) to oxidatively couple tyrosine and tryptophan residues to electron rich aniline derivatives. One of these reactions, a CAN-mediated oxidative coupling between anisidine derivatives and tyrosine residues, has been applied towards the synthesis of a novel protein-based material and the site-selectivity of this reaction has been explored using combinatorial peptides libraries. Overall, these unprecedented modification strategies target these under-utilized amino acids with excellent chemoselectivity, greatly augmenting the important and growing list of useful bioconjugation techniques.

Advisor: Francis, Matthew B
Essays in Weather Insurance and Development

Weather index insurance has been attracting much attention from academics and policy makers. When deciding whether and how much insurance to obtain, farmers face a trade-off: while an increasing acre coverage reduces the weather risk, it increases the basis risk. This dissertation investigates the demand for rainfall index insurance in India. Chapter 1 presents the subsidy experiment that was conducted in India and describes the key variables collected. It offers directions for quantitative research using the analyzed dataset. In Chapter 2, I particularly focus on the relationships among basis risk, weather risk, and the risk aversion of potential insurance buyers. Based on the subsidy experiment, I develop a structural model, and estimate the risk aversion parameters. The estimated risk aversion is found to be consistent with the observed inelasticity of demand for many farmers. I also show that a heterogeneity of socio-economic characteristics affects the level of the estimated risk aversion. I find that age, education, and literacy are negatively correlated with the estimated risk aversion. Finally, I derive an aggregate demand and conduct a counterfactual analysis to quantify the effect of basis risk. I find that basis risk is important enough that only farmers within approximately 4km to a weather station can actually reduce the overall risk by purchasing this insurance.

Advisor: Ligon, Ethan A