Essays in Development Economics

My dissertation focuses on several fields of study within economics. The common lens through which I ask all my questions is development economics. I employ health and public economics to aide in the interpretation and discussion of my analyses. Separately, my chapters explore issues related positive spillovers from overcompetition in contests, demand for financial services among low-income households, and the empowerment of women through access to guaranteed employment. Collectively, my dissertation offers evidence and insight regarding how we analyze and improve development initiatives that aim to change the lives of people who are poor or ill

Three Golden Balls: Pawn Shops and Crime

We ask what the relationship is between pawn shops and crime. The dominant narrative is that pawn shops reduce the transaction costs of crime and, consequently, promote it. We explore the alternative where pawn shops address the financial distress of those in need, which reduces the incentive to engage in crime. We exploit two distinct policies affecting access to pawn shops − severe licensing fees implemented in London in the early 1800s and state variation in the classification of pawn shops as essential businesses during the Covid-19 pandemic in spring 2020. For each, employing a difference-in-difference identification strategy, we provide evidence that restrictions to pawn shop access increases property crime

Save to Win: Using Contests to Promote Savings

We ask whether linking savings accounts to contests can promote saving. We do this by offering contest-linked accounts to individuals in rural Uganda where poverty is a serious problem. Our design builds off of results in experimental economics documenting excessive competitiveness in contests, with the goal of harnessing this behavior for the good. We find that, properly designed, we encourage savings beyond both pre-treatment levels and the control group. We explore reasonable heterogeneous treatment effects and document long lasting impacts on wealth

The Dwight Lee Reader: Collected Columns from the Freeman

A collection of articles written by economist Dwight Lee for The Freeman from 1976-2013. The articles are organized into sections on Basic Economics, Markets and Morality, The Market as a Process, Constitutional Economics, Government and Markets, International Trade, Social Welfare, and Environmental Policy

Bronco Ember An Edge Computing Acceleration Platform with Computer Vision

Bronco Ember is a nascent wildfire detection system that leverages edge computing capabilities, multi-spectral imaging, and artificial intelligence to greatly increase the performance of small satellite remote sensing payloads. The core hardware onboard is a SWIR InGaAs camera imaging in the 900nm to 1700nm wavelength and a GPU enabled single board computer. Artificial intelligence is used for fire detection and analysis using computer vision and neural networks being able to detect fires only filling a few pixels in each image. The system is based on traditional CNN networks and includes time series analysis that gives the system an 85% success rate in being able to detect wildfires with about a 50m diameter from a high-altitude balloon technology demonstration flight. The neural net is trained to monitor the movement and spread of the fire compared to prediction maps. This greatly reduces the number of false positive detected. The development of this payload has been supported through the NASA TechLeap Autonomous Observation Challenge No. 1 that has pushed the technology from concept to test flight in less than one calendar year. The system acts a rapid response remote sensing technology

Nano-to-Submicron Hydroxyapatite Coatings for Magnesium-based Bioresorbable Implants - Deposition, Characterization, Degradation, Mechanical Properties, and Cytocompatibility.

Magnesium (Mg) and its alloys have shown attractive biocompatibility and mechanical strength for medical applications, but low corrosion resistance of Mg in physiological environment limits its broad clinical translation. Hydroxyapatite (HA) nanoparticles (nHA) are promising coating materials for decreasing degradation rates and prolonging mechanical strength of Mg-based implants while enhancing bone healing due to their osteoconductivity and osteoinductivity. Conformal HA coatings with nano-to-submicron structures, namely nHA and mHA coatings, were deposited successfully on Mg plates and rods using a transonic particle acceleration (TPA) process under two different conditions, characterized, and investigated for their effects on Mg degradation in vitro. The nHA and mHA coatings enhanced corrosion resistance of Mg and retained 86-90% of ultimate compressive strength after in vitro immersion in rSBF for 6 weeks, much greater than non-coated Mg that only retained 66% of strength. Mg-based rods with or without coatings showed slower degradation than the respective Mg-based plates in rSBF after 6 weeks, likely because of the greater surface-to-volume ratio of Mg plates than Mg rods. This indicates that Mg-based plate and screw devices may undergo different degradation even when they have the same coatings and are implanted at the same or similar anatomical locations. Therefore, in addition to locations of implantation, the geometry, dimension, surface area, volume, and mass of Mg-based implants and devices should be carefully considered in their design and processing to ensure that they not only provide adequate structural and mechanical stability for bone fixation, but also support the functions of bone cells, as clinically required for craniomaxillofacial (CMF) and orthopedic implants. When the nHA and mHA coated Mg and non-coated Mg plates were cultured with bone marrow derived mesenchymal stem cells (BMSCs) using the in vitro direct culture method, greater cell adhesion densities were observed under indirect contact conditions than that under direct contact conditions for the nHA and mHA coated Mg. In comparison with non-coated Mg, the nHA and mHA coated Mg reduced BMSC adhesion densities directly on the surface, but increased the average BMSC adhesion densities under indirect contact. Further long-term studies in vitro and in vivo are necessary to elucidate the effects of nHA and mHA coatings on cell functions and tissue healing

Validity and Reliability of the Wahoo KICKR Cycle Ergometer

Cycle ergometers (CE) allow for the measurement of work and power during exercise. The Wahoo KICKR is an electronically-braked CE commonly used by coaches and athletes for exercise testing and training. PURPOSE: The purpose of this study was to determine the validity and reliability of the Wahoo KICKR CE for the measurement of power. METHODS: 12 recreationally active college students completed 3 separate workout sessions with 2 sessions on the Wahoo CE and 1 session on a mechanically-braked Monark CE. The order of sessions was randomized and counter-balanced. Seat height, handlebar height, and handlebar reach were also matched across trials. During the exercise sessions oxygen consumption (VO2) and heart rate (HR) were continuously measured. Following a 10-minute warmup, subjects completed an incremental exercise test consisting of 4, 5-minute stages starting at a work rate of 50 watts (W) and increasing by 50 W with each stage up to 200 W. Cadence was held at 71.5 revolutions per minute for all stages and trials. Validity was assessed by a dependent sample T-test comparing the first Wahoo session to the Monark trial. Reliability was assessed by a dependent sample T-test comparing the two Wahoo trials. RESULTS: HR and VO2 data across all trials and stages are displayed in the table. Both VO2 and HR were slightly lower when comparing the Wahoo to the Monark, but VO2 and HR were consistent when comparing the two Wahoo trials. CONCLUSION: This study showed that the Wahoo KICKR may slightly overestimate the work rate, particularly at higher workloads, but it is a consistent and reliable device. Based on these findings, coaches and athletes can have confidence incorporating the Wahoo CE into training programs and fitness testing. 50 W (n=12) 100 W (n=12) 150 W (n=12) 200 W (n=7) VO2 HR VO2 HR VO2 HR VO2 HR Wahoo 1 12.3 ± 1.4 101 ± 17 17.6 ± 2.3 118 ± 17 24.6 ± 3.5 145 ± 18 34.2 ± 5.2 160 ± 11 Monark 13.7 ± 1.6 102 ± 14 19.5 ± 2.0 122.8 ± 18 27.1 ± 3.4 152 ± 20 38.1 ± 6.9 167 ± 14 Wahoo 2 12.3 ± 1.5 98 ± 9 17.6 ± 2.6 118 ± 11 24.3 ± 3.4 144 ± 12 34.5 ± 4.6 161 ± 10 Validity P-value 0.004* 0.605 \u3c0.001* 0.009* \u3c0.001* 0.028* 0.011* 0.140 Reliability P-value 0.886 0.848 0.990 0.131 0.434 0.317 0.472 0.886 *p \u3c 0.05 All values represent mean ± S

Multiple origins of green blood in New Guinea lizards

© 2018 The Authors. Several species of lizards from the megadiverse island of New Guinea have evolved green blood. An unusually high concentration of the green bile pigment biliverdin in the circulatory system of these lizards makes the blood, muscles, bones, tongue, and mucosal tissues bright green in color, eclipsing the crimson color from their red blood cells. This is a remarkable physiological feature because bile pigments are toxic physiological waste products of red blood cell catabolism and, when chronically elevated, cause jaundice in humans and all other vertebrates. Although these lizards offer a promising system to examine the evolution of extraordinary physiological characteristics, little is known about the phylogenetic relationships of green-blooded lizards or the evolutionary origins of green blood. We present the first extensive phylogeny for green-blooded lizards and closely related Australasian lizards using thousands of genomic regions to examine the evolutionary history of this unusual trait. Maximum likelihood ancestral character state reconstruction supports four independent origins of green blood. Our results lay the phylogenetic foundation necessary to determine the role, if any, of natural selection in shaping this enigmatic physiological trait as well as understanding the genetic, proteomic, and biochemical basis for the lack of jaundice in those species that have independently evolved green blood

Galaxy interactions in IllustrisTNG-100, I: The power and limitations of visual identification

We present a sample of 446 galaxy pairs constructed using the cosmological simulation IllustrisTNG-100 at z = 0, with M_(FoF,dm)=10¹¹−10^(13.5) M⊙. We produce ideal mock SDSS g-band images of all pairs to test the reliability of visual classification schema employed to produce samples of interacting galaxies. We visually classify each image as interacting or not based on the presence of a close neighbour, the presence of stellar debris fields, disturbed discs, and/or tidal features. By inspecting the trajectories of the pairs, we determine that these indicators correctly identify interacting galaxies ∼45 per cent of the time. We subsequently split the sample into the visually identified interacting pairs (VIP; 38 pairs) and those which are interacting but are not visually identified (nonVIP; 47 pairs). We find that VIP have undergone a close passage nearly twice as recently as the non-VIP, and typically have higher stellar masses. Further, the VIP sit in dark matter haloes that are approximately 2.5 times as massive, in environments nearly 2 times as dense, and are almost a factor of 10 more affected by the tidal forces of their surroundings than the nonVIP. These factors conspire to increase the observability of tidal features and disturbed morphologies, making the VIP more likely to be identified. Thus, merger rate calculations which rely on stellar morphologies are likely to be significantly biased toward massive galaxy pairs which have recently undergone a close passage