Thesis (Ph. D.)--Stanford University, 1991. / Includes bibliographical references (leaves 212-216).

Thesis (Ph. D.)--University of Chicago, 1987. / Includes bibliographical references (leaves 116-123).

Thesis (Ph. D.)--University of Florida, 1989. / Description based on print version record. Typescript. Vita. Includes bibliographical references (leaves 91-94).

Thesis (Ph. D.)--University of California, Santa Cruz, 2000. / Typescript. Includes bibliographical references (leaves 149-154).

Thesis (Ph. D.)--University of Liverpool, 1989. / Includes bibliographical references (leaves 365-381).

Thesis (Ph. D.)--Ohio State University, 1985. / Includes vita. Includes bibliographical references (leaves 78-81). Available online via OhioLINK's ETD Center.

abstract: There is a nationwide gap in which African American, Hispanic and low-income students perform significantly lower than their peers. Research suggests that teachers hold lower expectations for these students resulting in lower achievement. There are four main factors that influence teacher expectations: stereotypes, teacher self-efficacy, school culture, language and formal policies and programs aimed at increasing teacher expectations. The purpose of this study was to inquire into the following questions: (1) What are the factors that influence teachers' academic expectations for low-income and minority students? (2) What are teacher's perceptions on the effectiveness of formal policies and programs that are aimed at increasing teacher expectations? More specifically, do teachers feel that top-down formal policies, such as teacher evaluations, uniform curriculum, and performance-based pay are effective in impacting their expectations, or do teachers believe that bottom-up policies, such as book studies and professional learning communities, make more of an impact on increasing their expectations? Ten teachers were interviewed in a school district that is consistent with the state and national achievement gap. The findings revealed that teacher expectations are influenced by the four factors I found in the research as well as two other factors: a cultural disconnect among teachers and students and teachers' level of motivation. A combination of top-down and bottom-up formal policies and programs are needed as teachers are individuals and all respond to various forms of formal policies and programs differently. / Dissertation/Thesis / Ed.D. Educational Leadership and Policy Studies 2011

The nonconscious processing of the mind is a prevalently studied body of research in the social psychology literature. The central focus assesses how priming of stimuli is able to activate trait concepts within the mind thus leading to cognitive and behavioral changes outside of the individuals' awareness or intent. Unfortunately, management scholars have failed to use this methodology to study organizational phenomenon. As such, it is the purpose of this research to apply a nonconscious thought processing lens to one of management's most studied areas, group processes. This dissertation proposes a model that accounts for the influence of priming on group processes. We conducted two studies measuring expectations regarding a specific work group (Study 1) and perceptions of group processes and performance on a group task (Study 2). To accomplish this, we utilized two priming techniques: subliminal (Study 1) and mindful (Study 2) to assess the influence of these nonconscious processes. In order to test our model, we used ANOVAs (Study 1) and ANCOVAs (Study 2) to measure the impact of priming on our dependent measures. We found the predicted results that priming is able to directly influence both expectations about groups and various group processes (i.e. group cohesion, group credibility, group coordination, and perceived loafing) during the performance of an actual group task as well as group performance (i.e. actual group behavior). Such results provide initial evidence that nonconscious processes can influence the expectations and performance of individual's to be more productive while working in groups. Most importantly, these results show that these changes can be made without the individual's awareness. Theoretically, these results provide additional support for organizational behavior scholars to include more nonconscious thought processing components in their current models. Future research should focus on the experiences individuals have with groups and how they can be used to shape the beliefs systems and subsequent behaviors when performing in groups. In other words, do individuals with positive past experiences inherently perform better, and prefer to work, in groups in the future?

It has been long hypothesized that due to the inherent ambiguities of visual input and the limitations of the visual system, vision is a form of “unconscious inference” whereby the brain relies on assumptions (aka expectations) to interpret the external world. This hypothesis has been recently formalized into Bayesian models of perception (the “Bayesian brain”) that represent these expectations as prior probabilities. In this thesis, I focus on a particular kind of expectation that humans are thought to possess – that objects in the world tend to be still or move slowly – known as the “slow speed prior”. Through a combination of experimental and theoretical work, I investigate how the speed prior is acquired and how it impacts motion perception. The first part of my work consists of an experiment where subjects are exposed to simple "training" stimuli moving more often at high speeds than at low speeds. By subsequently testing the subjects with slow-moving stimuli of high uncertainty (low contrast), I find that their perception gradually changes in a manner consistent with the progressive acquisition of an expectation that favours progressively higher speeds. Thus subjects appear to gradually internalize the speed statistics of the stimulus ensemble over the duration of the experiment. I model these results using an existing Bayesian model of motion perception that incorporates a speed prior with a peak at zero, extending the model so that the mean gradually shifts away from zero. Although the first experiment presents evidence for the plasticity of the speed prior, the experimental paradigm and the constraints of the model limit the accuracy and precision in the reconstruction of observers’ priors. To address these limitations, I perform a different experiment where subjects compare the speed of moving gratings of different contrasts. The new paradigm allows more precise measurements of the contrast-dependent biases in perceived speed. Using a less constrained Bayesian model, I extract the priors of subjects and find considerable interindividual variability. Furthermore, noting that the Bayesian model cannot account for certain subtleties in the data, I combine the model with a non-Bayesian, physiologically motivated model of speed tuning of cortical neurons and show that the combination offers an improved description of the data. Using the paradigm of the second experiment, I then explore the role of visual experience on the form of the speed prior. By recruiting avid video gamers (who are routinely exposed to high speeds) and nongamers of both sexes, I study the differences in the prior among groups and find, surprisingly, that subjects’ speed priors depend more on gender than on gaming experience. In a final series of experiments similar to the first, I also test subjects on variations of the trained stimulus configuration – namely different orientations and motion directions. Subjects’ responses suggest that they are able to apply the changed prior to different orientations and, furthermore, that the changed prior persists for at least a week after the end of the experiment. These results provide further support for the plasticity of the speed prior but also suggest that the learned prior may be used only across similar stimulus configurations, whereas in sufficiently different configurations or contexts a “default” prior may be used instead.

This dissertation examines the forecast model selection problem in economics in both theoretical and empirical settings. The forecast model selection problem is that there often exists a menu of different suitable models to forecast the same economic variable of interest. The theoretical portion of this dissertation considers agents who face this problem in two distinct scenarios. The first scenario considers the case where agents possess a menu of different forecast techniques which includes rational expectations but where the selection of rational expectations is costly. The assumptions that are necessary to include rational expectations as a choice are characterized and the equilibrium dynamics of a model under the appropriate assumptions is studied and shown to exhibit chaotic dynamics. The second scenario considers agents who possess a menu of econometric forecast models and examines the equilibrium outcomes when agents combine the different forecasts using strategies suggested by the forecasting literature. The equilibrium outcomes under these forecasting assumptions are shown to exhibit time-varying volatility and endogenous structural breaks, which are common features of macroeconomic data. The empirical portion of the dissertation proposes a new dynamic combination strategy for the forecast model selection problem to forecast inflation. The procedure builds on recent research on inflation persistence in the U.S. and on explanations for the efficacy of simple combination strategies, often referred to as the forecast combination puzzle. The new combination strategy is shown to forecast well in real-time out-of-sample forecasting exercises.