Theoretical Foundations and Empirical Evaluations of Partisan Fairness in District-Based Democracies

We clarify the theoretical foundations of partisan fairness standards for district-based democratic electoral systems, including essential assumptions and definitions not previously recognized, formalized, or in some cases even discussed. We also offer extensive empirical evidence for assumptions with observable implications. We cover partisan symmetry, the most commonly accepted fairness standard, and other perspectives. Throughout, we follow a fundamental principle of statistical inference too often ignored in this literature—defining the quantity of interest separately so its measures can be proven wrong, evaluated, and improved. This enables us to prove which of the many newly proposed fairness measures are statistically appropriate and which are biased, limited, or not measures of the theoretical quantity they seek to estimate at all. Because real-world redistricting and gerrymandering involve complicated politics with numerous participants and conflicting goals, measures biased for partisan fairness sometimes still provide useful descriptions of other aspects of electoral systems

Asset Accumulation, Information, and the Life Cycle

Empirical tests of the life cycle model have focused on its implications for the level of a household's total net worth and paid little attention to changes in portfolio composition over the life cycle. In this paper, we examine a new survey of the asset holdings of 6,010 U.S households and show that there is a pronounced life-cycle pattern to both the number and value of assets held by U.S. households. Direct survey evidence suggests that incomplete information is a significant determinant of household portfolio composition. We test the hypothesis that information about investment opportunities arrives stochastically over time, estimating a Poisson model for the arrival of new information.

Event-related potentials elicited by spoken relative clauses

Sentence-length event-related potential (ERP) waveforms were obtained from 23 scalp sites as 24 subjects listened to normally spoken sentences of various syntactic structures. The critical materials consisted of 36 sentences each containing one of 2 types of relative clauses that differ in processing difficulty, namely Subject Object (SO) and Subject Subject (SS) relative clauses. Sentence-length ERPs showed several differences in the slow scalp potentials elicited by SO and SS sentences that were similar in their temporal dynamics to those elicited by the same stimuli in a word-by-word reading experiment, although the effects in the two modalities have non identical distributions. Just as for written sentences, there was a large, fronto-central negativity beginning at the linguistically defined "gap" in the SO sentences; this effect was largest for listeners with above-median comprehension rates, and is hypothesized to index changes in on-line processing demands during comprehension

anchors: Software for Anchoring Vignette Data

When respondents use the ordinal response categories of standard survey questions in different ways, the validity of analyses based on the resulting data can be biased. Anchoring vignettes is a survey design technique intended to correct for some of these problems. The anchors package in R includes methods for evaluating and choosing anchoring vignettes, and for analyzing the resulting data.

Wealth and Portfolio Composition: Theory and Evidence

In this paper, we examine a new survey of 6,010 U.S.households and estimate a model for the allocation of total net worth among different assets. The paper has three main aims. The first is to investigate the extent to which a conventional portfolio choice model can explain the differences in portfolio composition among households. Our survey data show that most households hold only a subset of the available assets. Hence we analyze a model in which investors choose to hold incomplete portfolios. We show that the empirical specification of the joint discrete and continuous choice that characterizes household portfolio behavior is a switching regressions model with endogenous switching. The second aim is to examine the impact of taxes on portfolio composition. The survey contains a great deal of information on taxable incomes and deductions which enable us to calculate rather precisely the marginal tax rate facing each household.The third aim is to estimate wealth elasticities of demand for a range of assets and liabilities. We test the frequently made assumption of constant relative risk aversion.