VictorJuiz/thesis huggingface dataset:
"What every student should know and be able to do" [electronic resource] : the making of California's framework, standards, and tests for history-social science
Keywords: Education.

"What every student should know and be able to do": the making of California's framework, standards, and tests for history-social science abstract: This study explores California's standards-based reforms for history-social science education over the past twenty-five years. It focuses, in particular, on the development and interaction of the state's three primary history-social science policy documents: the History-Social Science Framework for California Public Schools, the History-Social Science Content Standards for California Public Schools, and the California Standards Tests for History-Social Science. The California Department of Education intends for the framework, standards, and tests to work in concert and promote the teaching and learning of history-social science. The standards define the content and skills that all students should learn across grade levels. The framework provides guidance for educators to implement the standards. The tests generate information about student achievement and hold schools accountable for implementing the standards. Through examining how these documents developed over the past two decades, this study argues that, rather than working together symbiotically to promote history education, California's history-social science framework, standards, and tests present educators with inconsistent, even antagonistic, strategies and materials to teach and assess history-social science.
What limits a stalled Argentine ant invasion? Effects of human-caused disturbance and resistance from a native ant [electronic resource]
Keywords: Biological Sciences.

When exotic species invade natural environments, they often cause destruction to native biological communities. In order to conserve native species, it is useful to understand what limits the extent of invasions. It is even more desirable to be able to predict where invasions will and will not occur. In this dissertation, I investigate the limits of an invasion at Jasper Ridge Biological Preserve by the Argentine ant (Linepithema humile). This invasion has been tracked since 1993 through twice-yearly ant surveys. Since 2001, the invasion appears to have stopped, and the interior of the preserve remains uninvaded. I observed how Argentine ants and native ants, particularly the native winter ant (Prenolepis imparis) responded to one another and to habitat, climate, and seasonal factors. At a small scale, weekly changes in Argentine ant presence within a few hundred square meters is limited by winter ant presence and microclimate effects. At the large scale of a whole natural area, the long-term spatial extent of Argentine ant invasion is closely tied to developed areas. Examining seasonal changes in Argentine ant and winter ant distribution on a hectare scale, it is evident that Argentine and winter ants affect one another differently in different habitats, and that Argentine ants have a stronger negative effect in sites closer to development.
Winner’s Curse and the Competitive Effect: Measuring Competition in the Viatical Settlement Market
Keywords:  Department of Economics
Stanford Department of Economics
winner’s curse
viatical settlement
competitive effect
common value auction
life insurance
Thesis

This paper attempts to develop a methodology for measuring competition in markets where the object for sale has a common but unknown monetary value. We do this by conceptualizing transactions in the viatical settlement market as first-price, common value auctions and deriving a parametric model for equilibrium bid functions. Within this model, we then estimate parameters and make observations about bidder behavior. Our analysis finds on average, fewer than five bidders compete for viatical contracts. We believe this is strong evidence of market power. Finally, by simulating comparative statics on the distribution of number of bidders, we conclude that at our estimated levels of competition, any evidence of winner’s curse was completely dominated by the competitive effect.
Wireless mesh networks [electronic resource] : protocol design and performance evaluation
Keywords: Electrical Engineering

With the increasing interest in multi-hop wireless communications networks, wireless mesh networks (WMNs) have emerged as an affordable and scalable solution to provide broadband packet data communications across wide geographic areas. However, due to the prohibitive complexity of analysis and simulations, studies on WMNs for large-scale applications have often oversimplified the physical and/or networking models. In this thesis, based on more realistic physical and networking models, we study the performance of large-scale WMNs that serve as access networks over large geographic areas. First, we create a new set of medium access control (MAC) protocols that incorporate such models. The protocols are designed within a time division multiple access (TDMA) and time division duplex (TDD) framework. Utilizing separate resources for control and data packets, the protocols provide mechanisms for network entities to explicitly cooperate among themselves for resource allocation in a fully distributed and adaptive manner. We also develop a large WMN simulator that implements the protocols and supports measurement-based models for radio propagation and interference calculation for a large built-in urban area. The simulator also captures the stochastic network behavior resulting from random traffic arrivals, admission control, and queueing. The enormous size and computational complexity of the simulator is addressed using a parallel-processing simulation technique that utilizes multiple processors interconnected with high-speed links and associated with large high-speed memory. Through extensive simulations incorporating such details, the performance of the WMNs is assessed under various simulation scenarios. First, it is demonstrated that an effective admission and congestion control (ACC) policy is critical to support stable user throughput under heavy traffic loads, and one of the ACC policies created in the thesis is shown to stabilize the network even under heavy traffic loads. Then, the scalability of the WMNs is investigated under different scenarios of network topology and routing metrics. The scalability behavior of several fundamental performance metrics is examined including the network throughput, per-session throughput, and blocking and dropping rates. Major factors are identified across the physical, MAC and routing layers that affect the scalability behavior, and the factors are shown to interact with one another in a complicated manner to determine the network performance. With more backbone support to the network, the network throughput and per-session throughput are shown to improve significantly, and the improvement is explained based on the aforementioned interactions across the layers of the network. The overall network performance is shown for two different routing metrics.
Wolves in sheep's clothing [electronic resource] : understanding modern state-building (and counterinsurgency)
Keywords: Political Science.

Since the end of the Cold War, the international community has become intimately involved in trying to strengthen weak and failed states. External actors, both multilaterally and unilaterally, have intervened in Europe, Asia, and Africa to bring internally conflicted parties together and to change the domestic authority structures of these countries. This dissertation explains how external actors can successfully contribute to the development of domestic authority structures in conflict-torn or post-conflict countries. Conventional state-building theories follow the Weberian conception of the modern state as an entity that maintains a monopoly over the legitimate use of violent coercion. Further, standard approaches to ending civil conflict recommend the use of population-centric strategies to achieve stability. These prevailing assumptions are problematic as they ignore a credible commitment problem that exists in conflict-torn societies: elites within the government and opposition have no incentive to disarm due to the rational fear that once they do so they will be taken advantage of by the opposing elites. This dissertation proposes a theory of self-enforcing stability to explain, from a rational-choice perspective, how it is possible to overcome this credible commitment problem. The theory contains four testable hypotheses. The first hypothesis is that an elite-centric, rather than population-centric, strategy will lead to greater success in establishing stability in conflict-torn states. Second, external actors contribute to the establishment of stability more successfully when they help nations establish limited access orders created by elite pacts rather than encouraging the creation of liberal democracies, or open access orders. Third, external actors must help internal actors overcome their underlying credible commitment problems by guaranteeing elite pacts. The final hypothesis is that the decentralization, or oligopolization, of violent means and rent-seeking opportunities balances power amongst elites, ensuring that competing elite groups can protect themselves from one another without threatening each other with overwhelming force. This dissertation finds support for the proposed theory's hypotheses in its examination of two cases: the Malayan Emergency from 1948-1960, and the stabilization effort in Iraq between 2006-2008, which includes the "Awakening Movement" and the "Surge. Both cases demonstrate how an external actor can contribute to developing enduring stability in conflict-torn societies by breaking from the standard Weberian conception of the state and population-centric focus. This dissertation concludes with a discussion of policy implications, based on the dissertation's findings, for current state-building efforts in Afghanistan.
Writing lessons [electronic resource] : case studies of beginning teachers
Keywords: Education.

This longitudinal, comparative case study of two large teacher preparation programs investigates how elementary teachers learn to teach writing. I follow nine teachers through their preservice preparation and first year of teaching. Using a cultural-historical activity theory framework (Engeström, 2001), I analyze settings for learning to teach writing in order to illuminate the features within and across settings that support or constrain learning. At the end of the preservice year, differences in teacher learning between cohorts were due to the degree of alignment between the methods course and the field placement and to the quality of instruction in the methods course. Importantly, I found that teachers in the stronger preparation program developed a cohesive set of tools, or conceptual framework for writing instruction, while graduates of the weaker program had a very limited repertoire of tools for teaching writing. This framework remained stable through the first year and guided teachers' decision-making. However, graduates from both programs needed more support in learning to teach writing across the grades and in acquiring the subject-matter knowledge needed to teach writing. Teachers entered the field with a tenuous grasp on how to teach writing, and their teaching quality in the first year depended largely on school and district support. Teachers who had focused grade-level and school/district support fared better than teachers who worked in settings that were unsupportive or settings that were supportive but unfocused. Writing curriculum played a significant role in many teachers' practices, regardless of other supports. Curricular materials varied in terms of the features of practice that were highlighted and the degree to which these features were explained. These differences afforded different opportunities for learning. Directions for future research and implications and for teacher education, administration, policy, and curriculum are discussed.
The X-ray power density spectrum of the seyfert 2 galaxy NGC 4945 [electronic resource] : analysis and application of the method of light curve simulations
Keywords: Physics

The study of the power density spectrum (PDS) of fluctuations in the X-ray flux from active galactic nuclei (AGN) complements spectral studies in giving us a view into the processes operating in accreting compact objects. An important line of investigation is the comparison of the PDS from AGN with those from galactic black hole binaries; a related area of focus is the scaling relation between time scales for the variability and the black hole mass. The PDS of AGN is traditionally modeled using segments of power laws joined together at so-called break frequencies; associations of the break time scales, i.e., the inverses of the break frequencies, with time scales of physical processes thought to operate in these sources are then sought. I analyze the Method of Light Curve Simulations that is commonly used to characterize the PDS in AGN with a view to making the method as sensitive as possible to the shape of the PDS. I identify several weaknesses in the current implementation of the method and propose alternatives that can substitute for some of the key steps in the method. I focus on the complications introduced by uneven sampling in the light curve, the development of a fit statistic that is better matched to the distributions of power in the PDS, and the statistical evaluation of the fit between the observed data and the model for the PDS. Using archival data on one AGN, NGC 3516, I validate my changes against previously reported results. I also report new results on the PDS in NGC 4945, a Seyfert 2 galaxy with a well-determined black hole mass. This source provides an opportunity to investigate whether the PDS of Seyfert 1 and Seyfert 2 galaxies differ. It is also an attractive object for placement on the black hole mass-break time scale relation. Unfortunately, with the available data on NGC 4945, significant uncertainties on the break frequency in its PDS remain.
Anger in the workplace [electronic resource] : effects of gender and frequency in context on social and job-related outcomes
Keywords: Sociology.

This dissertation explored expression of anger in the workplace through two experiments that varied in terms of the gender of the person expressing the anger, the frequency of the anger, and the object of the anger. Subjects reviewed resumes and performance reviews that they were told belonged to two consultants competing for the same promotion. Consultants who were said to express anger frequently were less likely to be promoted than neutral consultants. They also suffered social consequences, like being rated as less pleasant. Consultants who expressed anger a single time suffered social consequences (albeit less severe than those experienced by the frequently angry individuals) compared to neutral consultants, but their promotional outcomes were less affected. When respondents were given the option to promote both the neutral consultant and the angry consultant, most subjects chose to do so. The Study 1 results were based on an undirected expression of anger; Study 2 respondents were told that the anger was directed at a subordinate. A single instance of directed anger was more damaging to social and promotional outcomes than a single instance of undirected anger. Few gender effects were observed in either study, and the gender effects that were observed tended to favor females.
Applications of feedback control to musical instrument design [electronic resource]
Keywords: Electrical Engineering

In feedback control systems, the system variables being controlled—such as the velocity of vibrating strings or the position of motors—are estimated from sensor measurements, and the estimated information is fed back in order to influence the controlled variables. By controlling the system variables in this manner, the dynamics of the system can be fundamentally changed. We study how feedback control enables the design of radically new forms of musical instruments, with emphasis on two paradigms. The first paradigm is Feedback Controlled Acoustic Musical Instruments (FCAMI). Traditionally, musicians have owned many different kinds of acoustic instruments. Rather than requiring multiple instruments that have characteristic sound qualities, a musician might prefer to have a single instrument whose acoustics are essentially programmable. To achieve different or new sound characteristics, the musician could simply load a different instrument program, while the interface to the instrument would remain similar thus promoting skill transfer. We explain how to design feedback controllers with the goal of altering the dynamics of an acoustic instrument in musically salient ways. Positive real controllers are passive, so they are guaranteed not to add any energy to the acoustic musical instrument. As a consequence, they can be applied to any passive acoustic musical instrument in any configuration without driving it unstable. Finally, we relate positive real controllers to self-sustaining controllers for applications such as electromechanical bowing. The second paradigm is Haptic Musical Instruments (HMI). A haptic device can mechanically connect a musician to a virtual environment that synthesizes sound and provides force feedback. In this work, we study how to design the virtual haptic environment to assist a musician in making gestures to a musical instrument in a practical context. For example, the haptic drum provides a musician's drumstick with an extra push every time that the musician strikes the drum. This device allows the musician to make gestures that would otherwise be very difficult or impossible, such as arbitrarily long one-handed drum rolls and arbitrarily complex rudiments. To elucidate its behavior, we perform a nonlinear systems analysis of its dynamics. Next, we explain how to assist a musician in accurately selecting pitches from a continuous range on a Theremin-like haptic interface. We augment it with detents allowing the musician to feel the locations of equal-tempered pitches, yet the musician can still perform arbitrary pitch inflections such as glissandi, falls, and scoops. With the help of a subject test, we demonstrate that traditional detents as well as novel force-sensitive detents can provide accuracy improvements over simpler types of haptic feedback, such as spring feedback. In closing, we emphasize that the most appropriate type of haptic assistance depends on the task.
Are Bad Times Good for the Internet? An Empirical Analysis of the Shift to Internet Advertising During Recessions
Keywords:  Department of Economics
Stanford Department of Economics
advertising expenditure
online advertising
business cycles
internet advertising
recessions
e-commerce
Thesis

Internet advertising has several distinct benefits over more traditional advertising media such as television and newspapers. These include increased flexibility, cost effectiveness, targeting, and measurability. Given these advantages, it seems that internet advertising is ideally suited for times when budgets are constrained, and any marketing initiatives need to be strongly justified. This study explores whether there is a shift in the allocation of advertising expenditure towards online media as a result of recessions. A first step investigates whether the growth in internet advertising can be explained by the growth in sales in the field most closely tied to the medium: e-commerce. Next, the empirical results show that e-commerce does serve as a good baseline for explaining the growth in internet advertising, but that there is a separate, significant, and positive effect of the recession on internet advertising, both in dollar and share terms. A comparison to TV advertising expenditures shows that TV advertising does not exhibit similar behavior.
Autonomous ultra-low power ELF/VLF receiver systems [electronic resource]
Keywords: Electrical Engineering

ELF/VLF radio signals, from approximately 300Hz to 30KHz, are commonly used for submarine communications, ionospheric remote sensing, geophysical prospecting, and studies of the near-Earth space environment. Naturally occurring ELF/VLF emissions caused by nearly every lightning strike can be detected for thousands of miles and provide an abundance of wave-particle interaction possibilities in the radiation belts. Any applied studies of these events, however, require electromagnetic waves in the ELF/VLF band to be amplified, captured, analyzed, and stored. Specific studies often require the placement of receivers in extremely remote locations such as Antarctica or the middle of an ocean, and are almost always located far away from power sources to decrease noise. These scientific requirements drive the creation of new ELF/VLF receiver systems. Two new receiver systems were designed for use in terrestrial, typically Antarctic, locations. Both new systems utilize 10-100 times less power than the lowest-power comparable existing ELF/VLF receivers and were designed for remote unmanned operation in extreme environments without external power. The so called Penguin system, comprised of a hybrid microcontroller and FPGA architecture, removes the overhead of a general purpose CPU to provide the most streamlined processing for data acquisition possible while still maintaining a relatively traditional sampling architecture. The drastically reduced architecture of the Penguin system, compared to traditional receiver systems, on average consumes less power than a typical LED indicator lamp while capturing high fidelity ELF/VLF magnetic field snapshots every fifteen minutes. The low power and thermal requirements of the Penguin system enables low-cost remote studies of medium to large timescale phenomena such as Chorus and Auroral Hiss without the need for local power. The system has been deployed and operated at the United States Amundsen Scott South Pole Station in Antarctica. A second ELF/VLF receiver architecture, the VLF Advanced Technology platform, or "VAT", removes the typical CPU from the sampling and recording loop further reducing power requirements and physical system size while gaining the ability to record continuously. This radically new architecture enables future scientific studies of the fine structure in time and frequency of long-term events, such as the onset mechanisms of natural Chorus emissions, due to the extremely low power requirements. The system architecture is also greatly applicable to any continuous time recording system, including but not limited to acoustic and electromagnetic arrays for subsurface imaging systems, ionospheric remote sensing, and optical sensors.