49755 research outputs found
Sort by
Structured representations as a lens for meaning: reflecting and emitting content with Abstract Meaning Representation
No full textWhen we communicate with one another in language, among the conditions that make it possible for information to be reliably exchanged are two commonalities between the participants. First, we have access to a partial shared knowledge base, with some grounding that makes it possible for both participants to identify what is being referred to. Second, we have a common understanding of the structure of language itself, and more specifically the way in which information held in the mind is compressed into and extracted from language. Neither of these are immediately available to machines. Large pretrained language models appear to learn at least a functional approximation of both of these things. However, even as language models have grown more capable at generating fluent text, accessing world knowledge, and generally performing tasks that in humans we correlate with reasoning, their semantic unreliability has remained a constant. The persistent hallucinations, both pragmatic and factual, produced by language models starkly indicate that neither their understanding of the world nor their understanding of the rules of language at a semantic level are consistent with those of a human (if, indeed, such a thing as ``understanding'' even exists in the context of a language model).
The central question of this dissertation is this: how can we ensure that machines express meaning through language the same way humans do? We approach this problem by introducing an intermediate representation that describes the semantic structures used in the human mind, which we repurpose as an interface to model behavior. When used to analyze and evaluate text, this representation functions as a high-level content sketch that allows us to compare and identify common content across related texts. When used in generation, it becomes a content plan that lays out the desired content of output in a structured format, allowing us to specify surface-level details and modify the plan itself prior to realization.
In this work, we use as our interface Abstract Meaning Representation (AMR), a graph-based semantic representation that captures the types and relationships of concepts described in text. We explore three aspects of the usage of AMR in this role.
First, we study the practicalities of constructing and interpreting AMR graphs: we conduct a detailed analysis of error cases in prior methods of constructing a document-level graph from sentence-level components and design a new method that addresses these issues, yielding improved performance in the content selection phase of summarization.
Second, we explore their utility in directly comparing meaning, rather than form: we develop models for the novel task of AMR node alignment and propose two novel methods of AMR-based text evaluation that in part draw upon these alignment models. Finally, we apply AMR to generation: we demonstrate that using AMR as a content plan, in conjunction with pretrained language models, allows us to produce better-specified and more controllable outputs, at a finer granularity than previous work in controllable generation
Photophysics at the mesoscale: macromolecular engineering for multiexcitonic processes
No full textAs traditional solar technologies approach theoretical efficiency limits, novel approaches are necessary to continue to improve the power generation capacity of photovoltaics. Two complementary multiexcitonic processes, singlet fission (SF) and triplet-triplet annihilation upconversion (TTA-UC), show great promise in this field, allowing access to regions of the solar spectrum inefficiently harvested by silicon cells.
In designing and optimizing systems for SF and TTA-UC, macromolecular scaffolds are particularly attractive, enabling the simultaneous tuning of electronic coupling between chromophores as well as their intermolecular packing. The high modularity of these scaffolds allows for easy adjustment of component ratios or the introduction of new units to further adjust dynamics or morphology. As such, macromolecular systems have also been employed in various condensed and solid phase systems which may more readily be incorporated into photovoltaics. Herein, we expand the scope of macromolecular architectures to new domains for SF and TTA-UC.
In Chapter 1, we summarize the guiding principles for the optimization of these processes, and follow with a discussion of existing oligomeric, macromolecular, and self-assembled systems. In Chapter 2, an amphiphilic block copolymer (BCP) is introduced to explore SF in self-assembled micelles. We find that SF dynamics can be controlled by modifying BCP block ratios, as well as by co-assembly with a variety of dopants.
In Chapter 3, this amphiphilic BCP scaffold is adapted to TTA-UC, and we highlight the importance of micellar swelling in enabling this process. In Chapter 4, electron donors are incorporated into polymers alongside pendent SF chromophores to explore both intra- and intermolecular charge transfer. We observe the formation of long-lived charge separated states prompted by SF, with dynamics tunable by solvent polarity, donor strength, and mode of interaction.
And in Chapter 5, a series of hetero-oligomers are presented to explore SF at interfaces between classic acenes and the less-studied dipyrrolonaphthyridinedione. We reinforce the essential role of charge transfer states in mediating or deactivating singlet fission in a tunable fashion based on chromophore energetics. In sum, this work further demonstrates the essential role macromolecular engineering will play in the continued development of SF and TTA-UC
Statistical Methods for Understanding Social Issues
Get PDFThe modern-day abundance of both data and computational resources has expanded the potential for statistical methods to improve our understanding of social phenomena. Such insights can also serve as a basis for policy decisions and resource allocation. This thesis explores pragmatic approaches to statistical inference in select applications related to social issues.
We begin by considering underreporting of sexual assault on college campuses. Because many instances of sexual assault are never reported to authorities, the number of reported assaults does not fully reflect the true total number of assaults that occurred, and could arise from many combinations of reporting rate and true incidence. We estimate these quantities via a hierarchical Bayesian model of the reported data, drawing prior information from national crime statistics to help distinguish between reporting rates and incidence.
Next, we consider the task of detecting election interference, focusing on Ghana’s 2020 presidential election. Using locally-aggregated vote tabulation data, we construct a randomization test to screen for potential ballot box stuffing. After identifying regions with suspicious results, we estimate alternative vote totals under a counterfactual scenario with no election interference.
Next we turn our attention to synthetic control methods for causal inference. Using a motivating example of estimating the effects of exogenous economic shocks on support for political incumbents, we propose methods for leveraging shared information across multiple related studies.
Finally, we address the issue of data privacy. Motivated by the need to balance the utility of data analysis with protection of individuals’ privacy, we develop randomized optimization algorithms for differentially private statistical inference. These procedures allow the construction of private confidence regions, and employ a bias correction that improves empirical performance in small samples
What are you doing in my swamp? A case study of a community-led buyout and ecosystem restoration program in Staten Island, NY, from 2012 to 2024
Get PDFAs practical and effective nature-based solutions are more incorporated by communities, acknowledging realistic project implementation becomes imperative. Academics, subject matter experts, policymakers, and practitioners must ensure that funding, capacity, and support can be secured for long-term projects. By identifying key communication gaps, standardizing crucial definitions, and establishing long-term protocols, project implementation can be more consistent and streamlined. Managing proper communication and expectations between experts and community members is perhaps one of the most important skills any expert may possess and must be incorporated into best practices.
Keywords: managed retreat, nature-based solutions, New York (City), community-led buyout program, hurricane sand
The Path from Dialog to Individual Essay
Get PDFArgumentive writing is key to academic success, yet it is slow to develop and never mastered by many. Researchers investigating the development of argumentation have proposed a number of school-based interventions that aim to strengthen students’ argumentive writing. One such model is the Argue with Me (AMW) program, which focuses on the interpersonal context of argumentive discourse as a pathway to building a student’s skill in independent argumentive writing. Central to the method is students engaging deeply with a debate topic: first in peer-to-peer electronic dialogues, then with various reflective activities based on written transcripts of dialogues, and finally proceeding to individual independent writing on the topic.
Previous research has shown that students who participate in the AWM program improve their argumentation skills in both the electronic dialogues and subsequent independent essays, including transfer to new topics. Epistemic understanding of the purpose and value of argumentation has also been shown to improve. While the results from previous AWM studies are positive, independent argumentive writing remains far from proficient, with students continuing to struggle with integrating counterarguments into their writing, especially on a new topic where these have not been first introduced by another person in discourse.
Unlike many other intervention programs, the AWM model does not explicitly address writing. Hence, an augmented version of the AWM program was developed and evaluated in the present study. It included an experimental writing condition that was administered to twenty-three 6th grade students who participated in the AWM program during 12 class sessions over a period of 16 weeks. The remaining twenty-five students served as a comparison group. They participated in the AWM program but received no additional writing support.
Participants showed engagement and motivation in completing the AWM program; final individual essays did not show superior performance by students in the experimental writing condition, relative to intervention participants in the comparison group. The discussion reviews potential program and school factors that may have contributed to this outcome. Qualitative analyses of student work provide some additional insights, leading to the possibility of future AWM studies that incorporate writing supports, as well as potential implications for classroom practice
Unkoku Tōgan (1547–1618) and East Asia: Art and Patronage in Early Modern Western Japan
No full textThis dissertation examines the artworks of Unkoku Tōgan (1547–1618), an artist based in western Japan during the late sixteenth and early seventeenth centuries. Although Tōgan gained a reputation as an artist who inherited the legacy of Sesshū Tōyō (1420–1506), a celebrated master of ink painting, I aim to contribute a more comprehensive understanding of Tōgan’s oeuvre by examining it beyond this aspect alone. To this end, the study explores other dimensions of his career and paintings, with a particular focus on issues such as the role of patronage, the artist’s engagement with Chinese traditions, and cross-cultural elements related to Korea. I contend that the value of this thesis lies in its examination of Tōgan’s paintings through a lens that differs from those used in previous studies, thereby situating his works in a broader political and cultural context within East Asia.
Chapter 1 focuses on the analysis of Tōgan’s stylistic development in relation to and beyond that of Sesshū, exploring Chinese artistic traditions associated with the formal attributes of Tōgan. First, I argue that the stylistic changes evident in Tōgan’s works between the sliding-door paintings at Buttūji in Hiroshima and Ōbaiin in Kyoto may have originated from his receipt of Sesshū’s "Long Landscape Scroll" from Mōri Terumoto, an influential daimyo based in western Japan, who employed Tōgan as his painter-in-residence. This finding suggests a revised timeline for the granting of the scroll to Togan; I thus propose that the event occurred between 1597 and 1598, which differs from the generally accepted 1593 timeframe. Nevertheless, even after this occurrence, Tōgan persisted in utilizing pictorial languages that did not align with those of Sesshū, which suggests that Tōgan developed distinctive stylistic approach. With regard to this matter, I elucidate upon the visual elements in relation to the Chinese models that were among Tōgan’s inspirations
.
Chapter 2 centers on the topic of patronage, examining the background on the lineage of Sesshū, synonymous with the outset of the Unkoku school, as well as the role of Tōgan and his artworks in assisting his patrons. It is accurate to note that previous studies have already addressed the fact that Tōgan’s patron, Terumoto, gave Sesshū’s "Long Landscape Scroll" to Tōgan, thereby reviving Sesshū’s artistic lineage. However, the statement has been presented in a cursory manner, without any detailed account of the circumstances surrounding the event. I argue that Terumoto, at a time when the Mōri were in a political predicament, formalized the artistic legacy with the objective of promoting the cultural authority and political legitimacy of the Mōri clan, in relation to the Ōuchi clan who were the most dominant hegemony in western Japan during the medieval period. This chapter thus intends to shed light on the circumstances and motivations behind the occasion, as well as to conduct a critical analysis of Tōgan’s contributions and the function of his paintings within the project.
Chapter 3 offers an analysis of Tōgan’s Chinese figure paintings with an aim to clarify his relationship with the Kano school, with whom Tōgan is known to have trained, and of him as a man of culture. This chapter examines the thematic and stylistic associations with the Kano school, official painters serving the Toyotomi clan and the Tokugawa shogunate, affiliated with powerful elites in the capital. Despite Tōgan’s documented apprenticeship with the Kano school, it remains challenging to identify clear stylistic connections between his works and those of the Kano school, with the exception of a few examples, such as the landscape paintings of Buttsūji and the bird-and-flower screens in Tōshunji. In light of these considerations, I directed my attention to Tōgan’s Chinese figure paintings, which offer insights into this area. In my view, they appear to reflect a comparable approach to the Kano school in terms of their thematic choices and interpretations, which were likely tailored to cater to their military patrons with a political agenda. Moreover, previous studies have examined Tōgan’s status as a man of culture, but the majority of research has concentrated on his engagement with chanoyu, renga, and landscape paintings in the style of Chinese artists. To further illustrate this point, this dissertation took an alternative approach, investigating the unconventional iconography in his Chinese figure paintings, in relation to his familiarity with Chinese pictorial traditions and literature.
Chapter 4 presents alternative research regarding Tōgan’s working environment and engagement with Korean culture, delving into his relationships with Korean paintings in Japan. While previous studies have identified some connections between Tōgan’s works and Korean paintings, the discussions were brief, typically comprising a paragraph or so, and lacked sufficient elaborations on the ideas involved. This chapter addresses this issue by situating Tōgan’s works within a broader regional context and undertaking a detailed examination of the ways in which they were shaped by the cultural and traditional heritage of their environment. In order to achieve this, this study takes into consideration various determinants that could have impacted Tōgan's artistic output. Such factors included the social circumstances in western Japan during his career, the perception of Korean painting in Japan, comparisons with Korean models related to the Mōri family, and inscriptions by Korean figures on his paintings. Furthermore, this chapter conducts an in-depth examination of one of his Bodhidharma paintings, which has not been the subject of comprehensive analysis within existing studies. I consider this an important painting because it bears inscriptions by a renowned Korean diplomat monk, Priest Songun, and a prominent Japanese diplomat monk, Keitetsu Genso. The painting therefore serves to reveal the actual connections and communications between a local Japanese and a legendary Korean monk who mediated with Tokugawa Ieyasu for reconciliation. With the newly proposed approach, this study aims to reach a new understanding of Tōgan’s paintings in a synthesized manner in relation to Korea.
To summarize, Tōgan cultivated his own style by drawing upon a multitude of sources from the past and continental cultures and manipulated them in large formats, such as folding screens and sliding-door paintings. On the surface, he adapted his works to suit the needs of the new socio-political situation while decorating the residences of his patrons. At the same time, he was simultaneously striving to project his individual artistic identity as a man of learning from a warrior family. The multifaceted elements present in his artistic oeuvre mirror the dynamic era in which he was active
Ibn Khaldūn’s Muqaddima and the Maps of al-Idrīsī
No full textIt has long been noted that in compiling a geographical preface to his famous Muqaddima, Ibn Khaldūn relied on the maps contained in the twelfth-century geographer al-Idrīsī’s Nuzhat al-mushtāq fī ikhtirāq al-āfāq. Yet Ibn Khaldūn’s reading of nearly seventy regional maps of al-Idrīsī has not to date been the subject of a detailed examination. This article seeks, first, to establish patterns in Ibn Khaldūn’s map reading as recorded in the Muqaddima, noting the focus and direction of his reading as well as its omissions. In addition to his descriptions of the maps, it considers Ibn Khaldūn’s use of the text of the Nuzhat al-mushtāq and occasional examples of his updating and addition of information. Second, this analysis leads to a discussion of the significance—or lack thereof—of al-Idrīsī’s maps for the larger project of the Muqaddima: what role, in the end, did geography play within Ibn Khaldūn’s theory of history
Queering Ervah: Halachic Conceptions of Gender-Based Nakedness for the Modern World
No full textThis paper examines rabbinic conceptions of ervah—the halachic category for nakedness—and explores their application to modern, egalitarian, queer, and gender-queer contexts. Ervah is defined through two basic paradigms: (1) the objective paradigm, where genitalia universally defines ervah regardless of gender or cultural norms, and (2) the subjective paradigm, where gender and cultural norms greatly influence the relegation of body attributes to this category. Drawing upon tannaitic, medieval, and modern halachic sources, the paper evaluates traditional positions on ervah using three paradigms of gender definition: (1) genotype, (2) genitalia, and (3) phenotype, considering each paradigm’s impact upon transgender and intersex individuals. Further, it considers two primary interpretive approaches: (1) gender-inflexible, which assumes an all-encompassing heteronormative, cisgender framework, and (2) gender-expansive, which prioritizes the individual viewers’ sexual orientation and agency over assumed norms. Ultimately, the paper argues for a more fluid, gender-expansive approach to defining halachic ervah.
*Please Note*: This paper was written for Professor Emmanuel Bloch's Jewish Theological Seminary course, Gender, Halachah, and The Emergence of Tsniut as a Halachic Categor
“Unprecedented and Unparalleled:” The Last Step in Rabbi Kalonymus Kalman Shapira’s Altered Faith
No full textThis essay reexamines the final writings of Rabbi Kalonymus Kalman Shapira after the Grossaktion Warsaw, challenging the claim—most prominently advanced by Shaul Magid—that Shapira’s faith was “broken” at the end of 1942. Through a close analysis of two post-deportation sermon addenda and two letters buried in the Ringelblum Archive, I argue that R. Shapira did not abandon faith, but rather arrived at its final form: a faith marked not by rational theodicy or historical paradigms, but by radical submission to divine will and the continued potency of prayer. This “altered faith,” though stripped of explanatory frameworks, remains robust and deeply devotional—a final, faithful response to incomprehensible suffering
Editorial Introduction: Human Rights in Comparative and International Education
No full textNo abstract provided by the editor