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YUKI Atsusaka

Hello! I am a Ph.D. Candidate (political science) and M.A. student (statistics) at Rice University in Houston, Texas. Thank you for visiting my website!

My major is American politics and I am studying ranked-choice voting, race and representation and election reform. I am also interested in methodological research related to my substantive fields. My interests include rank data analysis, ecological inference, causal inference, survey methods, and quantitatively predictive logical models. My Curriculum Vitae is available here.

Working Papers

– “Unifying Demand and Supply-Side Theories of Minority Representation: A Logical Model” Under Review [Logical models + minority representation]
– “Bias-Corrected Crosswise Estimators for Sensitive Inquiries” (with Randy Stevenson) [Survey methodology]
– “Dual Effects of Vote-by-Mail Elections on Voter Turnout” (with Robert Stein and Andrew Menger) [Policy evaluation]
– “Race and the Demand for Legislative Responsiveness” (with Matthew Hayes) [Rank data + representation]
– “Causal Inference for Ranked Outcomes” (with Michelle Torres) [Rank data + causal inference]

Dissertation

In my dissertation, I work on three essays which intend to advance political science research by providing new statistical methods for analyzing rank and ecological data. The contribution of my work is two-fold. First, it introduces two entirely new fields of methodologies to political science — rank data analysis and optimal transport — which enable researchers to work on many problems in the discipline that they were not able to solve or even think of due to the lack of available tools. Second, it provides extensive empirical illustrations of the proposed methods to facilitate both substantive and methodological research in the new areas. Substantively, my project examines the consequences of an emerging electoral reform — switching from plurality rule to ranked-choice voting — on voters’ preferences and representation in the U.S.. My dissertation is supported by the Electoral Reform Research Group (New America) .

In “A Statistical Method for Partially Ranked Ballots,” I propose a novel statistical method for analyzing partially ranked ballots with strategic ballot concentration (plumping) within and across elections. This method, which generalizes the conventional approach to treat missing values in rank data, can be used to explain and predict the nature and variation of partially ranked ballots in ranked-choice voting (RCV) elections. I also provide new graphical representations of partial rankings within and across RCV elections, hypothesis test for strategic ballot concentration (plumping), clustering algorithms in the presence of plumping, strategy to include individual and aggregate covariates, and guideline for facilitating substantive interpretation. I illustrate the proposed model by attempting to resolve a controversy over the nature, size, and trend of partially ranked ballots in RCV elections in the U.S.

In “A Pitfall and Solution in Applied Ecological Inference,” I propose a novel class of ecological inference models for learning about individual-level properties when only aggregated data is available based on optimal transport. Existing methods fail to provide a guideline for and safeguard against common problems which emerge in applied ecological inference such as serious counting errors in ecological data and solutions are left to researchers’ discretion. To resolve this problem, I introduce an ecological inference model based on optimal transport and discuss how to use it along with existing methods to improve ecological inference. Unlike other approaches, the proposed model allows ecological data to contain counting errors in both marginals and also accommodates and learns from spatially correlated errors, which often appear in the construction of ecological data. I derive a fast algorithm for achieving exact inference on model parameters based on the Dykstra-Bregman method.

In “Does Ranked-Choice Voting Reduce Racially Polarized Voting?” (with Theo Landsman), I offer an empirical evidence for the moderation effect of the RCV implementation on the degree of racially polarized voting. To provide a valid causal effect of switching from first-past-the-post (FPTP) to RCV elections on racial polarization, I offer a novel measurement of racially polarized voting that is comparable across the electoral systems based on rank clustering methods and ecological inference. Moreover, I collect precinct returns and cast vote records from Bay Area mayoral elections from 1994 to 2020. With the measurement of racial polarization, I estimate the causal effect of the RCV implementation by dealing with structural missing values (no elections) in the collected time-series cross-sectional data.

Teaching

As an instructor, I have taught the Math Prep (aka Math Prefresher) for the first-year graduate students in 2018-2019, Social Analysis and Simulation in R for the second-year graduate students in 2019, and ecological inference in Advanced Political Methodology in 2019. In addition, I have worked (will be working) as a teaching assistant for Causal Inference (by Michelle Torres) in Fall 2019, Advanced Maximum Likelihood Estimation (by Randy Stevenson) in Spring 2019, and Machine Learning/Computational Social Science (by Michelle Torres) in Fall 2020. I am also an organizer of the Methodology Research Group in the Department of Political Science.

Background

I am a Fulbright scholar since 2016 and a founder of SHIPS (Seminar for Hiphop Studies), a study and social group on Black culture in Kyoto, Japan. Before moving to Houston, I studied African American History and Culture and Hiphop in an M.A. program (American Studies) at Doshisha University in Kyoto, Japan. I still got the vision like a line between two dots ÷ !


I will be presenting my work at the PolMeth Online on June 17. Looking forward to seeing you there!