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Publication Analysis and Improvement of Algorithms for Continual Area Sweeping(2024-09-15) Patrick ZhaoThis paper addresses the single-agent continual area sweeping problem by providing an analysis of prior works and proposes a data-driven approach for more realistic scenarios of event occurrences. The single-agent continual area sweeping problem is a non-uniform extension of the single-agent area coverage problem where there are areas on a map with events occurring with Bernoulli probability per time step. In particular, thedistribution of event occurrences on the map is unknown to the agent. The goal of the agent is to maximize the number of events detected as well as minimize the average event detection time. This paper focuses on the variant of the continual area sweeping problem where the number of events per region is bounded and expands on prior work by removing assumptions about the sparsity of event occurrences. Specifically, we improve on a previous heuristic by implementing heuristic search algorithms and test reinforcement learning algorithms on the task. Finally, we implement an U-Net for predicting event occurrences that are caused by spatial relations between environment features for modeling more realistic scenarios, improving upon detections per second by 77% and decreasing average detection time by 56% when compared to a uniform sweep strategy.Publication Assessing the Impact of Currency Movements on Investor Demand for International Equity ETFs: An Analysis of Hedged Equity ETFs(2024-08-27) Wiig-Andersen, DidrikExchange Traded Funds (ETFs) have become a leading investment vehicle since State Street introduced the first U.S. ETF in 1993. Despite their popularity among both professional and retail investors, limited research has been conducted on international ETFs. These products hold assets such as equities or bonds in regions outside the U.S., introducing foreign exchange risk. This study examines whether currency-hedged ETFs experience increased inflows when the local currency depreciates or becomes more volatile relative to the USD. The analysis compares these inflows to those in unhedged ETF counterparts. Bivariate and multivariate regression analyses were performed using 1-, 3-, 6-, and 12-month currency price changes, currency price volatility, and index returns as independent variables. The results indicate a statistically significant relationship between short-term index returns and the inflow of funds into hedged ETFs for the respective regions. However, none of the other explanatory variables, including currency price changes or volatility, demonstrated statistically significant effects. One possible explanation is that during turbulent times—often marked by currency depreciation and heightened volatility—illiquidity and mispricing in international ETFs may cause investors to refrain from selling unhedged ETF shares in favor of purchasing the hedged counterpart. Further research is recommended to identify factors that more accurately capture the drivers of fund flows in international ETFs.Publication Assessment of Isla Urbana’s Rainwater Harvesting Systems and Their Applicability in Appalachia(2024-09-20) Djoko, Grace; Odlum-Hobson, YochiPublication An Exploration of Autonomous Quadrotor Trajectory Planning(N/A, 2023-09-15) Yijie LuIn this project, I explored a variety of algorithms used quadrotor trajectory planning and implemented each algorithm from scratch. Quadrotor trajectory planning is a pivotal part of autonomous quadrotor systems. These algorithms enable quadrotors, or drones, to autonomously navigate complex environments, performing a wide range of tasks. From surveillance and aerial photography to search and rescue operations, quadrotors are used extensively in applications requiring rapid and agile movement. Accurate trajectory planning ensures obstacle avoidance, stable flight, and efficient use of resources.Publication The Impact of Carbon Pricing Policies in Reducing CO2 Emissions from Road Transportation: A Meta-Analysis of Empirical Studies(N/A, 2023-08-21) Didrik Wiig-AndersenTo achieve the 2030 climate goals outlined in the Paris Agreement, global carbon dioxide (CO2) emissions must be reduced. Prevailing literature and economic theory emphasize the role of carbon pricing policies as a fundamentally critical and cost-effective approach in mitigating these emissions. However, there is currently limited evidence substantiating this claim, thereby restricting governmental understanding and implementation of effective pricing policies. The paper performs a comprehensive literature review of empirical studies assessing the impact of pricing policies in reducing emissions from road transportation, a sector responsible for over a tenth of the global CO2 emissions. In particular, the paper aims to contribute by 1) presenting existing literature that has studied the influence of carbon pricing policies on emissions from road transportation; 2) exploring the types of carbon pricing policies governments have implemented in their effort to mitigate CO2 emissions; 3) detailing the quantified impacts of these policies; and 4) identifying the contributing factors driving effective policies and understanding the challenges that limit the impact of less effective ones through a discussion. The sample comprised eighteen studies—both peer-reviewed and gray literature—published between 2017 and 2023, analyzing eight different types of pricing policies across forty-six countries. First, the results suggest that there exists a positive relationship between the magnitude of the fee levied as part of the policy and the CO2 emissions reductions, regardless of the type of policy. Second, policies priced continuously and directly—encouraging reduction of every gram of CO2 per kilometer—were found to be more effective in reducing vehicle CO2 emission rates when compared to policies priced according to emission bands and thresholds. Third, the results show that registration and fuel taxes were seen to reduce the prevalence of high-emitting vehicles (>180gCO2/km) in the vehicle fleet, while similar to circulation taxes, promote the adoption of diesel vehicles. This study augments existing literature, reinforcing the established notion that combined policies offer the most potent reduction effects, given their ability to collectively address multiple factors influencing consumer decisions in vehicle selection (extensive margin) and vehicle usage (intensive margin). Further research is recommended to identify effective policy combinations.Publication Surgery for Patients in Extremis: Reasonable Care or Surgical Futility?(2015-01-01) Patel, SagarCritically ill patients in extremis often undergo abdominal exploration despite the subjectively high incidence of morbidity and mortality. To evaluate the efficacy of intervention, records of patients undergoing laparotomy while in extremis by the Acute Care Surgery service at an academic medical were retrospectively reviewed. Outcomes were stratified by patient demographics, primary service, surgical findings, preoperative physiology, and mortality. Overall mortality was 55.6%. Surgical bedside explorations revealed a mortality rate of 53.3% without identified abdominal pathology and 90% with identified pathology. Significant differences in survival were noted for Lactate level, vasopressor use, acute kidney injury, leukocytosis, and anemia. Therapeutic bedside exploration’s extremely high mortality rate likely represents futile care. OR procedures for patients in extremis also carries significant mortality that may be predicted by preoperative physiology. This data suggests that surgical consultation for patients in extremis should be scrutinized for efficacy prior to offering surgical intervention.Publication Finding Passion and Purpose: A Study of How Wharton Students View Work and Life(2015-01-01) Davidson, LeahWhat does it mean to lead a meaningful life and find work that is congruent with your values? In an increasingly global and competitive talent marketplace, how do companies reduce attrition and improve performance by providing experiences that are both attractive to applicants and fulfilling to workers over the course of their careers? My research proposal involves a study of how companies create environments to attract and retain talent, with a focus on the priorities of Wharton students and how they choose internships and careers post-graduation. Inspired by a longitudinal study conducted by the Wharton Work/Life Integration Project, this report uses a literature review, interviews, quantitative data analysis, and a case study to understand how Wharton students’ values change over time periods (between undergrads in 1992 and 2012) and across educational levels (between current undergrads and MBAs).Publication Effects of Bank Mergers on Risk Leading Up to the 2007-2008 Mortgage Crisis(2016-01-01) Kim, JinAhRecent highly-publicized bank mergers following the home mortgage crisis of 2007-2008, often the result of bank failure or insolvency, brought attention to the issue of consolidation within the banking industry. The banking system has seen increases in consolidation at national levels, with the largest banks gaining increasingly greater proportions of market share. This merger activity and the existence of such “too big to fail” institutions has attracted concern about potential moral hazard due to perceptions about government bailouts and dangers posed by under-capitalized banks. Literature on the topic has found connections between merger activity and increased leverage, as well as a positive association between risk-taking and leverage, exacerbated in larger banks; together, this suggests that mergers may indirectly have an effect on risk-taking behavior in financial firms. This paper explores a possible link between M&A and risk in the context of the financial crisis of 2007-2008.Publication Factors Affecting Vaccination Demand in the United States(2015-01-01) Ruan, MichaelA multitude of healthcare economics research has been focused on determining the optimal vaccination rate in the United States; many of these studies propose taxes or subsidies as vehicles through which society can achieve the determined ideal uptake. However, there is no guarantee that price adjustments can necessarily change individuals’ behavior. To reach a given target uptake, it is therefore necessary to understand what motivates their decision-making. This study applies the Berry, Levinsohn, and Pakes (1996) method to calculate price elasticity for vaccinations most commonly obtained by children to enter school and finds demand to be extremely price inelas- tic. Furthermore, regression analyses conducted in this study find that positive attitudes toward vaccination greatly improve the odds of vaccinating, and also discover strong correlation between certain demographic variables and attitudes towards immunizations.Publication The Economics of Orphan Drugs: The Effectiveness of Priority Review Vouchers on the Development of Drugs to Combat Neglected Tropical Diseases(2015-01-01) Warshaw, RobNeglected tropical diseases (NTDs) such as malaria and cholera affect more than 1.4 billion people a year. Pharmaceutical companies have historically neglected these diseases, as the affected populations are also some of the world’s poorest. In 2007, a bill was signed into US law that created a Priority Review Voucher (PRV) program. This program grants developers of drugs for neglected diseases a waiver that reduces the time needed for FDA drug approval. This waiver can be sold to other pharmaceutical companies hoping to expedite the process for potential blockbuster drugs. This law is still in its early stages at the time of this paper, and it would not be feasible for any drugs to be fully approved due to the long drug development timeline. By analyzing FDA clinical trial data, though, initial trends can be analyzed for the development of drugs for NTDs. The clinical trial data does not fully support the effectiveness of the PRV program, but recent sales prices support that the market incentives are working correctly.