Browsing by Subject "Representation"

The inferior colliculus (IC) is an auditory midbrain nucleus essential to the perception of sound frequency and the localization of sound source; yet it remains unclear how the firing rate of primate IC neurons contribute to the localization of concurrent sounds of variable sound frequencies. In this work, I extracellularly recorded the activity of 105 IC neurons while two adult macaque monkeys reported the location(s) of either a single bandpass filtered sound or two concurrent bandpass filtered sounds spatially separated by 24° and separated in sound frequency by 0.25 - 2 octaves. Monkeys performed this task well, with an accuracy of about 80% on single sound trials and about 90% on dual sound trials. The improvement in performance on dual sound trials was not explained by dual sound modulations of IC neural response functions. On dual sound trials, IC neuron receptive fields broadened, and sound frequency accounted for less variance in the dual sound response; and these changes decreased the performance of a maximum-likelihood decoder in correctly labeling the condition of a held out dual sound trial by about 20%. Overall, these results suggest that changes to the IC neural response functions elicited by the presence of a second, concurrent, sound should impair rather than facilitate the IC encoding of concurrent sounds and that an alternative explanation is required to account for monkey performance. I next investigated if recently discovered response alternations, suggested to underlie the encoding of concurrent sounds, were present in the recorded populations. These response alternations occur when an IC neuron alternates its firing rate between the rate corresponding to each component sound of a dual sound pair. These response alternations were observed in about 60% of IC neurons and their contribution to the population response remained stable across the full, 2 octave, range of frequency separations tested. Thus, response alternations are a general mechanism used by the IC to potentially facilitate the encoding of multiple sounds and these results add to a growing body of work observing response alternations across brain areas. The measurements I performed clearly indicate that neurons in the primate IC are sensitive to not only sound frequency and location but also the number of sounds in the environment. Future empirical and theoretical work is needed to elucidate how exactly these response alternations arise and are read out by downstream neurons to allow for the perception of concurrent sounds.

Why do agents react to economic shocks privileging their identities and distrust of elites over their economic interests? This dissertation argues that this paradox can be explained by the logic of democratic representation. In a democracy, citizens delegate their economic interests to elites and institutions and forge a \emph{long-run relationship} with them. It shows that three factors -trust, identity and economic aspirations- regulate this relationship, and the fact that conflicts are processed within it can explain two puzzles: a) why economic disagreements arise while economic conditions remain unchanged and b) why economic shocks result in polarization or populism.

Firstly, it looks at the link between living standards and anti-establishment politics after financial crises. It pools 250 opinion and spending surveys and shows that unfulfilled economic aspirations undermine the trust in elites and institutions. Citizens protect their economic interests making their trust contingent on their economic aspirations. Financial crises undermine their well-being, and the ensuing decline in trust can interact with pre-existing political identities, and polarize politics along lines apparently unrelated to economic deprivations.

Secondly, it examines the link between affective polarization and economic expectations looking at 27 European countries since 1993. It identifies partisan bias looking at how citizens react to cabinet shifts. It shows that citizens with identical fundamentals but different identities update their subjective expectations in opposite directions. It argues that partisan bias is driven by affective polarization: the polarization of elites increases the hostility towards opponents, and citizens express it through their subjective expectations. However, bias does not push citizens to act against their economic self-interest. I reject alternative explanations about the source of bias including (a) lack of information (b) disagreements over the expected effects of government policy or its competence.

These findings suggest that democracy can transform the experience of citizens of economic antagonisms into conflicts with elites or about identity. However, trust and identities do not diminish the impact of economic factors, it only makes it more complex.

Scientific models are used to investigate reality. Here “model” refers to a representation which is created by an agent for a particular inferential purpose. These purposes include but are not limited to explanation, prediction, exploration, classification, and measurement. Through modeling, scientists become capable of understanding the composition and structure of natural systems and social systems in a systematic manner constitutive of scientific research. This process of understanding is underwritten by a logical structure distinctive to scientific modeling.

Throughout this dissertation, I articulate, justify, and defend a specific account of the logical structure of scientific modeling. In order to do so, I detail economic models, which I contend are representative of general scientific modeling. Broadly, my account of scientific modeling can be decomposed into three distinct claims. First, I argue for understanding scientific modeling in terms representation. Following others, I then conceptualize representation in terms of purpose and relevant similarity. However, against this conceptualization are numerous counterarguments, which I proceed to detail and then disarm.

Second, I argue that the ideal scientific model is a useful model. Connectedly, I contend that in order for a scientific model to be useful, it must first be idealized. In order to demonstrate the necessity of idealizations for scientific modeling, I begin by detailing a number of idealization strategies and demonstrate how they are integral to the use of scientific models across the natural and social sciences. But in order to demonstrate that idealized models are not only useful but are ideal, I dismantle the putative ideal of completeness which holds that the ideal model completely represents reality in all its detail and complexity. However, as I demonstrate, completeness is neither achievable nor a legitimate aspiration for working scientist.

Third, I argue that in order to use scientific models, it is often necessary for scientists to alter them in order to better fit particular target systems. In order to explain the alteration process, I detail the representational continuum found across the sciences which stretches from highly concrete data models to highly abstract principles. Between these extremes are theoretical models and empirical models. In order to construct such models, scientists must engage in an exploratory process by which possibilities are mapped and relative likelihoods estimated. In this way, scientists can construct highly specialized models which can allow them to better pursue specific inferential purposes. All of this results in a division of inferential labor and associated efficiency gains which, I argue, are constitutive of scientific progress.

American voters understand that elections have consequences, but they have become so disillusioned by their political system that approximately 40 percent have self-selected out of the two-party circus, choosing instead to identify as independent or unaffiliated which often requires them to forego their primary election voting rights. They understand that the process no longer serves its intended purpose of providing for representative government. Nevertheless, when it comes to elections, Americans get it wrong in just about every way possible. They spend so much time debating which superficial features of the electoral system—voter ID laws, polling place hours and locations, voter registration deadlines, etc.—are destroying the political process that they overlook the real cause of its decay: that political parties exercise control over the rules of the electoral system.

At the end of the day, people want a government that works. It is quite clear that the political system we have now simply does not allow for that. Less obvious are exactly why this is so, and what can be done. The role of this paper, then, is as a sort of citizen’s primer to our electoral crisis. I begin by tracing the origins of American political parties and describe how they and their agents in government mold the electoral system to their advantage in getting and maintaining control of government. Next, I discuss the ways in which that system is so deleterious to stable, functioning government and “national attachment” in the body politic. I then propose an alternative electoral system that would allow for fair and effective representation of more people, helping to rebuild the necessary trust and confidence in our fundamental political institutions. Finally, I reflect on the dangers of continuing to use a system in which political parties—private organizations—abuse state power and the fundamental institution of democracy—the election—to protect and advance their private interests, and how institutional collapse might be avoided.

Prior to the Civil Rights Movement, fewer than 50 Black judges had been elected or appointed to the judiciary. As of August 2015, there are over 1,000 Black state and federal judges. As the number of black judges has increased, one question arises: have American courts been altered purely by this substantial increase? One expectation—and, at times, a prediction—behind the increased descriptive representation of Black judges is that their mere presence would alter the judiciary. It was supposed that these judges would substantively represent Black interests in the decisions they made. In other words, it was suspected, and predicted, that Blacks in the judiciary would enhance equality and justice by being aware of, responsive to, and advocating for African Americans. This theory about the likely role of Black judges derives from theoretical work on political representation and racial group consciousness, and empirical studies of Black elite behavior in other political institutions.

Despite such predictions, there is no corresponding scholarly consensus regarding whether Black judges possess a racial group consciousness and have racially distinctive judicial behavior. Therefore, the theory undergirding the demand for increased diversification, as a means to transform the judiciary, remains unsubstantiated. This is precisely where this project, “They’re There, Now What?: The Identities, Behavior, and Perceptions of Black Judges,” seeks to intervene in and explore, if not settle, the matter of whether black judges possess a racial group consciousness and exhibit racially-distinctive judicial behavior. It addresses a set of interrelated questions relevant to understanding whether we can view Black judges as representatives in ways that are similar to how we view other Black political officials. I examine these questions using a multi-method approach. For my analyses, I draw on diverse materials: the published biographies of every Black judge appointed to the federal bench, a survey experiment with a nationally-representative adult sample, and semi-structured interviews with 30 Black judges.

This research, which engages with scholarship on representation, group consciousness, judicial behavior, and candidate perceptions, offers new insights into the lives, perceptions, and behavior of Black judges, as well as the manifestations of Black substantive representation in the judiciary. My dissertation argues that, despite the general reluctance to use the term “representation” when referring to judges, we can consider Black judges as representatives. Black judges behave as substantive representatives by (1) sharing and understanding the experience, history, and perspectives of Black Americans, (2) challenging language, persons, policies, and laws they feel negatively affect, or violate the rights and liberties of, African Americans, (3) respecting African American litigants, and (4) ensuring the rights of African Americans are protected and the needs of black Americans are being met.

Only through research that considers the perspectives, identities, perceptions, and behavior of Black judges will we arrive at a more comprehensive understanding of the importance of racial diversity in the courts. As this project finds, a link between descriptive representation and substantive representation can, and frequently does exist within the judicial context. Such a link is significant given that Blacks’ liberty and justice through the American legal system continues to be subject to those who exercise judicial power. This dissertation has implications for the discourse surrounding the need for increased descriptive and substantive representation of Blacks in the judiciary, and the factors that affect representation in the justice system.