VictorJuiz/thesis huggingface dataset:
Lapsing while learning : how attentional fluctuations hinder memory formation
Keywords: Psychology.

The human brain has a remarkable capacity for retaining the details of our everyday lives over long stretches of time. Part of what enables this feat is our ability to attend to certain details, while neglecting others. Our ability to stay focused on the world around us also wavers, and lapses of attention can contribute to which experiences we ultimately remember or forget. In this work, we build on decades of research into how attention during memory formation affects long-term outcomes. We do so by complementing a basic science approach with investigation of an emerging societal trend -- media multitasking, or habitually consuming multiple streams of media concurrently. Heavier media multitasking has been associated with an array of cognitive differences, including sustaining and directing attention, and forming short- and long-term memories. In Chapter 2, we leverage functional magnetic resonance imaging (fMRI) to measure the neural impact of distraction and its interactions with memory formation. We find a clear detriment to behavioral measures of memory performance, but neural findings suggest that internal distraction or mind blanking may play an important role as well. Specifically, heavy media multitaskers' poorer memory performance may be driven by a hyperactive "bottom-up" attentional network. Thus, in Chapter 3 we employ pupillometry to index attentional lapsing throughout a battery of sustained attention, working, and long-term memory tasks. We find two distinct patterns in our results: pupillary effects on long-term memory performance are associated with those predicting sustained attention task error rates, and media multitasking-related deficits in working memory performance can be accounted for by baseline pupil differences, response times indicating attentional lapses, and relative deficits in sleep duration. Collectively, these findings support the notion that attentional lapsing contributes to in-the-moment failures to encode experiences into lasting memories. Furthermore, individual differences in the ability to build memories of our everyday lives (such as those tracked by media multitasking) may be largely attributable to these lapses.
Large-scale neocortical dynamics and information processing underlying a sensory decision
Keywords: Electrical Engineering.

Sensory perception is fundamentally limited by the coding accuracy of sensory neural ensembles. Although a substantial body of work suggests that populations of sensory neurons exhibit correlated fluctuations that may bound the precision of neural coding, the extent to which these fluctuations extend across multiple cortical areas and interact with sensory coding during active animal behavior remain poorly understood. To examine the impact of correlated fluctuations on information coding and communication across sensory cortical areas, we imaged the Ca2+ activity of > 21,000 individual neurons across 11 neocortical areas in mice performing a Go/No-Go visual decision-making task. Multiple neocortical areas accurately encoded the visual stimulus, as well as the animal's decision to respond. Our analysis also revealed positively correlated noise fluctuations across neural populations in multiple neocortical areas. The mean strength of these noise correlations varied as a function of time across the visual stimulus presentation, delay, and response periods of our decision-making assay. Notably, sensory cortical neurons generally exhibited noise fluctuations that were more positively correlated at the start of visual stimulation, but then less so as a decision-making trial proceeded. Our results reveal that 60% of the total power of cortical variability stems from correlated fluctuations of neural populations spanning multiple distinct cortical areas. The strongest cortical fluctuation was a decision-coding activity mode that encompassed all brain areas under observation. We also found several fluctuation modes that encoded visual stimulus information but were shared across fewer brain areas. Overall, our analyses suggest that information regarding sensory stimuli and perceptual decisions are processed and shared between cortical areas through mutually non-interfering orthogonal channels. The timing of informative activity in these channels suggests that sensory information is first processed through intercommunications between multiple sensory areas, followed by a propagation of the final decision to all cortical areas involved.
Laser shaping and streaking for x-ray free-electron lasers
Keywords: Physics.

Lasers have been a versatile tool in facilitating x-ray free-electron lasers in various components of the machine. At the beginning of photocathode injectors, the properties of the drive laser determine the initial distribution of the electrons. Laser heater has been widely used to modulate electron bunch energy spread in order to suppress collective instabilities arising from dispersive sections in the accelerator. Interaction between optical lasers and the electron beam can be used to manipulate the phase space of the electron bunch to produce desirable shapes in the x-ray emission. After the x-ray photons have been generated, optical lasers are used in synchronization with the x-ray pulse to study dynamics in atomic and molecular systems. Moreover, they can provide single-shot diagnosis of the x-ray pulse, such as laser streaking, to extract valuable information about the x-ray pulse itself and the dynamic system under analysis, which can be challenging to probe directly. In this work we examine laser applications specifically in the Linac Coherent Light Source (LCLS). In the first half of the thesis, we focus on laser shaping techniques applied to the injector drive laser and the laser heater, in both spatial and temporal domains. We further discuss ghost imaging as an application of laser shaping in accelerators and its potential to be used in other x-ray and electron imaging experiments. In the second half, we switch gear to laser streaking as a measurement tool for attosecond x-ray pulses. We discuss in detail the generation of attosecond x-ray pulses at LCLS and present exciting results of the first single-shot characterization of such extremely short pulses using laser streaking.
LEADERSHIP DURING CONFLICT: WHERE CHARISMATIC LEADERSHIP FALLS SHORT
Keywords:  Department of Communication
Leadership
conflict
Tesla
Chrysler
Stanford Department of Communications and Journalism
Thesis

What is effective leadership during crisis? This thesis explores how leaders ought to best handle different forms of crisis, by examining how Elon Musk and Lee Iacocca respectively dealt with the crises at Tesla and Chrysler. Musk’s charismatic leadership, which incorporated narcissistic qualities and an inflated sense of confidence, led him astray when dealing with Tesla’s financial issues and driver fatalities. The public response to Musk’s decisions, as exemplified through stock changes, sheds light on the impact of Musk’s choices during the various crises he dealt with. Iacocca’s transformational leadership, in contrast, helped empower his subordinates to work together to mitigate the dire financial situation at Chrysler. The effectiveness of his approach is examined through production sales. These two case examples shed light on how leadership style influences crisis management, and when they can go wrong.
Learning, decision-making, and inference with limited experimentation
Keywords: Electrical Engineering.

Over the last decade, machine learning techniques have revolutionized a variety of disciplines including medicine, natural language processing, computer vision, and finance. With this central role that machine learning has in our lives, there exists a vital need to fully investigate the applicability of these techniques, especially in human-centered domains. Indeed, many assumptions behind the theoretical analysis of machine learning algorithms are not satisfied in practice, which can lead to harmful consequences in sensitive applications. One example is in medical decision-making, where the impact of wrong decisions may be severe and irreversible. Furthermore, despite these huge advances in machine learning, the traditional randomized controlled trials are still the gold standard for testing the efficacy of various treatment and policy interventions. Although these trials are very robust and valid with minimal (or no) assumptions, they are very expensive and difficult to run, especially in medical applications. Thus, it is also important to carefully design and customize machine learning techniques that under a mild set of assumptions can provide meaningful and valid guarantees about the treatment effects using observational data. Observational data are usually more accessible and have the advantage of bypassing the burden of running experiments. This doctoral dissertation focuses on designing and analyzing data-driven methods with limited experimentation, focusing on three different settings. First, we study the online setting, where the decision-maker needs to personalize treatment decisions sequentially and wishes to reduce the amount of experimentation (randomization). In the rest of this dissertation, we consider the offline setting where the decision-maker has access to some observational data and wishes to estimate and draw inference about treatment effects. Specifically, we consider panel data models and discuss the treatment effect estimation using matrix completion methods. Moreover, we analyze personalized (non-parametric) inference from observational data with high dimensional covariates and combine non-parametric estimators with sub-sampling techniques to provide valid confidence intervals that are able to adapt to a priori unknown lower-dimensional structure of data.
Learning or herding? Understanding social interactions and the distribution of success on a social music sharing platform
Keywords: Business.

Digital sharing platforms like YouTube and SoundCloud crowdsource the process by which users can discover high quality new products among an increasingly vast flow of new products, acting as on-going digital test markets. Social features on these platforms can accelerate the discovery process by encouraging sharing of information and facilitating learning, thereby reducing the number of people sampling poor quality products. This may more quickly concentrate platform traffic on higher quality alternatives. Social features may also include a feedback loop if people care about consuming the same products as their peers. Given previous research showing that social feedback loops can distort or even invert the relationship between product quality and product popularity, if such feedback loops exist, the discovery and filtering capabilities of crowdsourcing may be compromised, emphasizing the need to understand the nature of social interactions on such platforms. Utilizing data from SoundCloud, a music sharing and streaming site, I develop an approach to separately identify and measure these two separate endogenous social effects with and without feedback loops. Results suggest that the platform's social features do have informative effects but that the feedback loop plays a dominant role for the most successful songs.
Learning to Learn: Metaplasticity Improves the Temporal Precision of Motor Learning
Keywords:  Symbolic Systems Program
Symbolic Systems
Metaplasticity
Motor Learning
Cerebellum
Thesis

In order to facilitate motor learning, the brain is thought to implement a supervised learning process whereby errors in performance are incrementally compensated for through the adjustment of the neural synapses that were responsible for causing the error. While artificial neural networks can easily perform these adjustments, the brain faces the difficult problem of receiving reports about performance errors at a nontrivial delay, thus requiring that rules governing the induction of synaptic plasticity are in place to ensure that only the synapses that caused the error are adjusted. Recently, our lab has shown that the cerebellum, the brain region that supports motor learning, solves this problem for oculomotor learning by selectively adjusting the strengths of synapses that were active 120ms prior to the report of an error – the same amount of time necessary for error feedback to reach the cerebellum. Recent findings from our lab further suggest that this temporal rule for the induction of plastic changes is not genetically hard-coded, but rather that the brain must actively learn it through experience of the 120ms visual feedback delay.
Here, we report two fundamental findings. First, we show that this metaplasticity, or the tuning of the synaptic plasticity rules, affects the timing of oculomotor learning. Using a well-characterized form of oculomotor learning, we show that without visual experience, and thus without experience of the visual feedback delay, animals adjust eye movements at a delay relative to animals with normal visual experience. Second, we provide first evidence for adult metaplasticity using this behavioral correlate. We show both that dark-reared animals are able to significantly improve the timing of oculomotor learning after adulthood rehabilitation to visual experience, and that eliminating adulthood visual experience in normally-reared animals impairs the timing of learning.
Legal innovation in archaic Greece : the case of monumental written laws
Keywords: Classics.

This dissertation examines legal innovation in archaic Greece, through the lens of monumental written laws. Adopting a quantitative approach of the existing corpus of archaic legal inscriptions, I strengthen the case that absence of evidence is evidence of absence and subsequently challenge the traditional narrative about the uniform spread of monumental written laws. I show both that there were several paths of legal innovation, notably in Crete where most our inscriptions are from, and that monumental written laws are the odd phenomenon that must be explained. In so doing, I offer new perspectives on the conditions of possibility of such monumental written laws. Lastly, I use innovation theory to study both the diffusion patterns revealed by this dissertation and the likely causes and consequences of legal innovation in the form of monumental written laws.
Let's not see open access as a threat : convergence and divergence among research librarians and academic publishers on public access to the scholarly literature
Keywords: Education.

The now widespread recognition of the benefits of open access (OA) to research and scholarship has brought the global system of scholarly publishing to a historic turning point, as well as an impasse as the key stakeholders differ on how best to achieve the goal of universal OA. This thesis builds on quantitative work measuring the progress of OA by analyzing the positions and values of research librarians and scholarly publishers around this topic. Utilizing a survey of librarians (n = 188) and interviews with commercial and nonprofit publishers (n = 20), participants were asked to respond to a model of OA involving "subscription-equivalent transition" in terms of library costs, to solicit what was valued and what was most concerning. It was found that librarians and nonprofit publishers generally agreed that OA is integral to the future of scholarship; which was not the case among commercial publishers, who were qualified in their support, to the point of seeing it as potentially detrimental to scholarly publishing. Both sets of stakeholders recognized the dangers posed by library free ridership under OA publishing models. Librarians viewed subscription-equivalent arrangements more favorably than other dominant OA models. Both commercial and non-commercial publishers considered the subscription-equivalent model not an attractive option, but with varying justifications: nonprofits perceived greater risk due to their smaller market share, while commercial publishers sought to preserve their profit-making and growth imperatives. Librarians and publishers were mixed in their perceptions of the prevailing article processing charges (APC) model: it was recognized among some librarians as a viable transition path for some disciplines, and by others as inefficient and unscalable. Some publishers saw APCs as desirable an OA for providing authors with a choice. These results suggest, in the short term, opportunities for cooperation between librarians and nonprofit publishers to engage in cooperative models—that leverage mission alignment, financial transparency, and assurance contracts to sustain revenues—to transition from selling content to OA publishing service models. Despite findings of damaged trust between both parties, librarians indicated their willingness to enter into financially neutral models. Rather than seeing OA as a threat, the vastly greater potential for open science to address global issues suggests we are at a historic moment: where, through mutual compromise and reconciliation, we may achieve a digital information commons through cooperation.
Lifely: Help your aging loved ones plan for the lives they want
Keywords: Stanford Graduate School of Education
Learning Design and Technology
LDT
end-of-life
end of life
dying
difficult conversations
Lifely
Thesis

Many families struggle with end-of-life planning conversations for a variety of personal, cultural, and religious reasons. Those who want to have such conversations can be uncertain about how to approach the topic; this difficulty can be further exacerbated when there is a generational gap. As a result, many families avoid these conversations altogether. However, putting off the conversation until it cannot be avoided (e.g., in times of medical emergency), makes the conversation and necessary decisions even more stressful. Having these vital discussions earlier helps ensure people can live life the way they want, through the end. It also lowers the burden on caretakers and other loved ones.
This report describes Lifely, a new website (planwithlifely.com) designed to help adults in their mid 20s to late 30s prepare for, have, and reflect on end-of-life planning conversations with their parents. Lifely provides a suite of exercises to help families come to the best possible conversations and solutions for everyone. Lifely leverages expert perspectives and helps users focus on how people want to live (rather than on death). By encouraging users to have these conversations sooner, Lifely makes having end-of-life planning conversations more personal and joyful.
Lights, Camera... Asians: Hollywood’s Quest for Success in the “Asian Box Office”
Keywords:  Department of Communication
Communication
Movie
Film
Box Office
Asia
China
South Korea
Japan
Hollywood
Asian American
Thesis

This thesis analyzes Hollywood’s attempts to create films that succeed in Asian markets, while still achieving success within the domestic box office. Through analysis of 2018 global box office information of South Korea, Japan, and China and 13 case studies on specific films from the past two decades, I examine whether two strategies have been effective in generating cross-cultural success: 1) the use of actors and directors of Asian descent; and 2) cross-cultural content that attempts to appeal to both American and Asian audiences.
In my quantitative analysis of the 2018 box office data, I found that the most consistently successful Hollywood films in Asia were action/superhero movies. For the most part, these top- ten Asian market films do not have significant Asian characters and were nevertheless extremely successful in China, Japan, and South Korea. The case studies reveal that the use of Asian talent and cross-cultural content has been successful for some films, but largely when targeted toward specific Asian countries. I conclude that for many studios and production companies, a more financially viable strategy may not be to attempt to succeed in the “Asian Box Office” because of the diversity and segmentation the various Asian populations. Instead, the most effective and financially lucrative strategy may be to target the needs of smaller subsets of the “Asian Box Office,” such as a national or ethnic identity. Furthermore, I found that Asian diasporic audiences (such as Asian Americans) may have more shared cultural identity across ethnic differences than Asian populations in Asia. This trend is corroborated by the financial and critical success of films like Searching and Crazy Rich Asians, not only in subsets of Asian audiences, but also in ethnically diverse American audiences.
Linguistic belonging : how teacher-student interactions about language use shape elementary students' experiences of belonging
Keywords: Education.

We use language constantly—to communicate our desires, to show our competencies, and to present who we are to the world. In American classrooms, White and wealthy ways of using language often dominate. These ways of using language are sometimes considered right, standard, and professional. Yet our students bring a rich diversity of language use to our classrooms, a richness that often goes undervalued in educational settings in which teachers feel they must, and do, emphasize dominant ways of using English. The ways in which teachers interact with students about their language use can influence the linguistic belonging of students from nondominant linguistic backgrounds—their sense of being valued, included, and recognized in positive ways for how they use language. This study explores the instantiation of linguistic belonging for students in two Bay Area elementary classrooms, including examining teachers' plans and perspectives, interactions about language use themselves, and students' reactions to these interactions. I find that the ways in which teachers give feedback to their students, the perspectives teachers hold about students' language use, and instances in which teachers instruct dialogically—that is to say when they value student input and accept multiple answers from students—influence the linguistic belonging of students who speak in nondominant ways in these two classrooms. Additionally, I find that conversations about the relationship among language, race, and power hold untapped potential in terms of linguistic belonging in these settings. The findings of this study develop the construct of linguistic belonging, contributing to theoretical work in educational linguistics and social psychology. They also suggest practical classroom applications—ways that teachers can enhance the linguistic belonging of their students in real classrooms on a daily basis.
Linguistic fundamentals in earnings press releases
Keywords: Business.

I re-examine the information content of earnings press releases (EPRs) by distinguishing tone, which captures optimism and pessimism and is the focus of prior research, and linguistic fundamentals (LF), which captures information content in non-tone language. I find after controlling for standard firm characteristics, LF positively predicts future cash flows, unlike tone, which generally negatively predicts future cash flows. I document a return continuation in LF, in contrast to the return reversal in tone documented in prior literature. My findings distinguish informative content in LF and misleading content in tone in EPRs.