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Earnings Extrapolation and Predictable Stock Market Returns
No full textThe U.S. stock market’s return during the first month of a quarter correlates strongly with returns in future months, but the correlation is negative if the future month is the first month of a quarter, and positive if it is not. These effects offset, leaving the market return with its weak unconditional predictive ability known to the literature. The pattern accords with a model in which investors extrapolate announced earnings to predict future earnings, not recognizing that earnings in the first month of a quarter are inherently less predictable than in other months. Survey data support this model, as does out-of-sample return predictability across industries and international markets. These results challenge the Efficient Market Hypothesis and advance a novel mechanism of expectation formation
Iron-Based Microstructures For Biodegradable And Non-Biodegradable Applications
No full textTraditional microfabrication techniques for microelectromechanical systems (MEMS) have emphasized silicon and silicon-related materials. As more MEMS applications emerge, including the Internet of Things (IoT) and biodegradable applications, widely expanded materials sets are being considered. Since iron (Fe) has good electrical and magnetic properties, it undergoes degradation in moist or oxygenated environments, and since it is prevalent in both biological and environmental systems, it is being seriously considered as a candidate material to satisfy these new needs. In this dissertation, we developed iron-based microstructures for use in biodegradable and non-biodegradable applications. Specifically, electrical interconnects were developed with biodegradable iron/polymer composites. From the materials perspective, electrical, mechanical, and electrochemical properties of the composite material under physiological degradation were investigated. Stable electrical resistivity of the composite was shown over 20 days in degradation, even if under mechanical straining. Good adhesion to similarly biodegradable substrates of the composite was also shown in degradation. Further, the biodegradability of the composite was demonstrated by characterizing its degradation behavior. From the application perspective, a functional lifetime of over 4 days of the electrical interconnects with the packaging was achieved under physiological degradation to prove the capability of iron-based materials in biodegradable applications. In addition, miniaturized step-up transformers with laminated electrodeposited iron-alloy cores were developed. From the materials perspective, the magnetic permeability of the iron-alloy thin films at micro-scale thicknesses was characterized to demonstrate the retained magnetic properties of these materials at smaller scales. From the application perspective, the performance of the transformers was characterized at the device and circuit level to demonstrate the utility of iron-based bulk material in non-biodegradable magnetic applications. Finally, electrostatically tunable inductors fabricated from iron/ceramic composites were developed. From the materials perspective, the magnetic permeability tunability of the iron/ceramic composites was demonstrated. From the application perspective, the reasonable tuning ability of the device with minimum power consumption was shown to prove the utility of iron-based composite materials in non-biodegradable magnetic applications
The Quantification of Neural and Behavioral Chromatic Sensitivities
No full textThe first stage of human color vision is the encoding of light by the long (L), medium (M), and short (S) wavelength sensitive cone photoreceptors. These signals are subsequently recombined into three post-receptoral pathways, two chromatic opponent and one luminance. The two chromatic pathways take the difference of cone activity (L-M and S-(L+M)) and the third luminance pathway sums the cone activity (L+M). Beyond the level of these post-receptoral mechanisms, the computations performed and their location in the brain are not well characterized. Across two studies, we examined the sensitivity of the underlying chromatic mechanisms using both functional magnetic resonance imaging and psychophysics. In both types of experiments, we employ the use of ‘silent substitution’ which allows for the selective modulation of activity of cone photoreceptors, and their combinations. In the first experiment, we collected BOLD fMRI responses in human V1 to spatially uniform, temporal chromatic modulations that systematically vary in chromatic direction and contrast. From this, we found that within the LM cone contrast plane, V1 is most sensitive to L-M contrast modulations and least sensitive to L+M contrast modulations. Within V1, we observe little to no change in chromatic sensitivity as a function of eccentricity. In the subsequent experiment, we measured the temporal impulse response functions associated with tracking chromatic Gabor patches and measured how the lag functions change as a function of chromatic direction and contrast, confined to the LS cone contrast plane. We measured detection thresholds for stimuli matched in their spatial, temporal, and chromatic properties. We found that for both tracking and detection, within the LS cone contrast plane, the underlying mechanisms are most sensitive to L-isolating contrast modulations and least sensitive to S-isolating contrast modulations. Across all experiments, we developed color-contrast separable models that allow us to model the relative sensitivities of the chromatic mechanisms in a way that is independent from the effect of contrast. We use these models to further quantify the sensitivities of the underlying chromatic mechanisms. This work advances our understanding of human color perception and places important constraints on building more generalized models of color processing
The Slow Burn: Young Alumni Reflections on Short-Term Intercultural Learning Experiences Organized by Independent High Schools
No full textSchools and nations are engaging in conversations about the future of education, including the question of how best to prepare students for their future in a complex, interconnected, and often volatile world. Student learning and education redesign should focus on the knowledge, skills, and dispositions students need to bring greater and more equitable sustainable development to their communities and tackle the global challenges they will face—collectively termed global competence. Many educators are considering ways to increase student development of global competence through various learning experiences and initiatives. This study focused on one type of these learning experiences—school-organized programs that immerse students in international contexts for short-term learning experiences during high school. This mixed-method study focused on young alumni of these programs and on better understanding how these learning experiences have lived with their participants over time, including any self-reported global competence development specifically related to intercultural communication, perspective taking, and adaptability. The study’s findings reflect that most participants report global competence development when there was opportunity for relational learning. Participants also report continued meaning-making and influence of these experiences in their lives since high school, often through their resulting disposition for continued intercultural engagement. There are two areas of note that were exceptions to these general findings, namely that participants of programs with a service focus came to see the service aspects of their global learning as problematic, and that participants with a transnational and/or immigrant identity were not well served by these learning experiences, because their existing global competencies were not accounted for in program design. A dialectic approach that centers intercultural relational learning can support high school students in global competence development and have continued influence on them beyond adolescence as they grow to understand the world and themselves as young adults
Greek Epic Parody and the Classical Life of Heroic Epic Poetry
No full textThe extant corpus of Greek epic parody is small and difficult to circumscribe. Scholars have largely considered fragments of hexameter epic parody in isolation without contextualizing them alongside parodic epic allusion in comedy and iambus. Modern theoretical approaches to parody that emphasize the importance of strict formal categories have encouraged this approach. However, the semantic breadth of the Greek term paroidia, from which “parody” is derived, suggests that epic parody must also be approached as a trans-generic literary phenomenon. With this in mind, I examine how parodies of heroic epic in different genres from the sixth to fourth centuries BCE engage with the contemporary “life” of heroic epic: how it was consumed, how its poet was imagined, how it related to other genres and verse forms, and what knowledge or insight it was understood to contain. This guiding principle informs close comparative readings of fragments and passages that use the language or formal elements of heroic epic to comic or critical effect. Primary case studies include Hipponax fr. 126 Degani, Hegemon fr. 1, Aristophanes’ Peace 1270-1304, Strato Comicus fr. 1, and Matro of Pitane fr. 1; discussions of many other examples appear for context. I begin by offering foundational interpretations for a few important but understudied fragments, and showcasing the variety of ways in which imitation of epic language and form may invite the epic world into a contemporary comic setting (chapter 1). Each subsequent chapter focuses on a different aspect of the lived experience of epic poetry in the sixth to fourth centuries and examines how parodists invoke these contemporary practices and phenomena to make epic speak to current issues; topics include modes of epic performance (chapter 2); the close relationship of epic with other literary and subliterary verse forms (chapter 3); and the role of epic in educational and intellectual developments (chapter 4). By this approach, I offer richer interpretations of some difficult poetic fragments, fresh literary historical contexts for more canonical passages, and new insights into the life of epic poetry in antiquity
Essays in Macro-Finance
No full textIn the first chapter, I show that the long-term decrease in the nominal short rate since the 1980s contributed to a decline in banks\u27 supply of business loans, firm investment and new firm creation, and an increase in banks\u27 real estate lending. The driving force behind these relationships was the shift in banks’ funding mix from time deposits (CDs) to savings deposits, which was caused by the decrease in the nominal rate. I show that banks finance business lending with time deposits because of their matching interest-rate sensitivity and liquidity. A lower nominal rate reduces the spread on liquid deposits (e.g., savings deposits), leading households to substitute towards them and away from illiquid time deposits. In response to an outflow of time deposits, banks cut the supply of business loans and increase their price. The decrease in business lending leads to reduced investment at bank-dependent firms and a lower entry rate of firms in industries that are highly reliant on external funding. I document these relationships both in the aggregate, and in the cross-section of banks, firms and geographic areas. For identification, I exploit cross-sectional variation in banks\u27 market power and business credit data. I develop a general equilibrium model which captures these relationships and shows that the transmission mechanism I document is quantitatively important. In the second chapter, joint with Caterina Mendicino, Kalin Nikolov, Juan Rubio-Ramirez and Javier Suarez, we examine optimal capital requirements in a quantitative general equilibrium model with banks exposed to non-diversifiable borrower default risk. Contrary to standard models of bank default risk, our framework captures the limited upside but significant downside risk of loan portfolio returns. This helps to reproduce the frequency and severity of twin defaults: simultaneously high firm and bank failures. Hence, the optimal bank capital requirement, which trades off a lower frequency of twin defaults against restricting credit provision, is 5pp higher than under the standard default risk models which underestimate the impact of borrower default on bank solvency. In the third chapter, joint with Martina Jasova and Caterina Mendicino, we show that a reduction in lender of last resort (LOLR) policy uncertainty positively affects bank lending and propagates to investment and employment. We exploit a unique policy that reduced uncertainty regarding the availability of future LOLR funding for banks as a quasi-natural experiment. Using micro-level data on banks, firms and loans in Portugal, we generate cross-sectional variation in banks\u27 exposure to uncertainty and find that the size of the haircut subsidy - the gap between private market and central bank security valuations - plays a key role in the propagation of the shock to lending and the real economy
Data Sanctorum: The Corpus Kalendarium Database of Devotional Calendars
Get PDFThe Book of Hours was the popular personal religious manuscript of the medieval period, and the vast majority of the surviving examples begin with a devotional calendar of saints and feasts. The Corpus Kalendarium Database, or CoKL DB, is a database of these manuscripts and their calendars, recording the saints and feasts, and cross linking them to allow querying by metadata of the manuscript or calendar itself, or the presence and rank of a particular observance or group of observances. This paper presents an introduction to the underlying relational database, the user interface, and some of the ways that this data-driven system can present manuscripts which would be impossible with the physical objects
Collation Model for Ms. Codex 1047: [Liber tastharium domini Batide Rolandi et Polafoli].
Get PDFInventory of properties in southeast France.https://repository.upenn.edu/sims_models/1147/thumbnail.jp
Exploring sustainable degrowth-based adaptation to climate change-aggravated water insecurity in parts of rural India: A gender relations approach
Get PDFThis article reviews the theoretical concept of ‘sustainable adaptation’ to climate change and water scarcity using a gender-relations approach by answering the following questions: i) What is a sustainable adaptation to climate change? ii) Based on a literature review, how does gender interact with climate change adaptation to water scarcity and droughts in rural India? (iii) How do the concepts of sustainable adaptation, degrowth, and gender relations interact on the ground, pertaining to water justice?
The paper argues that climate change adaptation and development goals can harmonize only if they rectify root causes of vulnerabilities. For adaptation actions to yield sustainable outcomes, they need to be embedded in a just degrowth politics that transforms unequal power relations, including gender relations with water. In India, degrowth is about ecological, economic, and social justice that calls for transformation of the economy. This transformation looks into the lifecycle of goods - how goods are produced, composed, assembled, distributed, consumed, and regenerated today; further degrowth strategy explores alternate, just, non-extractive, decolonial, and democratically-led trajectories that sustain the web of life. This paper discusses five interrelated principles of sustainable degrowth-based adaptation that center on community-based notions of water and gender justice
Does financial education in high school affect retirement savings in adulthood?
No full textSince individuals are increasingly required to manage their own retirement portfolios, policy levers that increase retirement planning and saving have become increasingly important. We use variation in timing and presence of state-required personal finance coursework in high schools to estimate the effect of the financial education coursework on the likelihood of holding and amount in retirement accounts in adulthood (ages 25–40). Our results show no definitive increases in account ownership, non-retirement investment accounts, or homeownership. Since prior work finds required high school financial education improves credit and debt outcomes, we recommend that states and educators prioritize content that is more immediately relevant for 18-year-olds, such as budgeting, long-term debt, and credit