Underperformance in affluence: the remarkable relative decline in American heights in the second half of the 20th-century

Objective: We use the complete set of NHES and NHANES data collected between 1959 and 2004 in order to construct trends for the physical stature of the non-Hispanic white and black US adult population and compare them to those of Western- and Northern-Europeans. Method: Regression analysis is used to estimate the trend in US heights stratified by gender and ethnicity holding income and educational attainment constant. Results: US heights have stabilized at mid-century and a perio0d of stagnation set in with the birth cohorts 1955-74, concurrent with continual rapid increases in heights in Western and Northern Europe. The American population had been the tallest in the world for two centuries until World War II, but by the end of the 20th century fell behind many of their European counterparts. Only since the most recent birth cohorts 1975-83 is some gain apparent among whites but not among blacks. The relationship between height and income and between height and educational attainment has not changed appreciably over time for either men or women. Conclusion: We conjecture that the American health-care system, as well as the relatively weak welfare safety net might be the reason why human growth in the United States has not performed as well in relative terms as one would expect on the basis of income. The comparative pattern bears some similarly to that of life expectancy insofar as the US is also lagging behind in that respect

Spatial Correlates of U.S. Heights and BMIs, 2002

Aiming to further explore possible underlying causes for the recent stagnation in American heights, this paper describes the result of analysis of the commercial U.S. Sizing Survey. Using zip codes available in the data set, we consider geographic correlates of height such as local poverty rate, median income, and population density. We find that after adjusting for variables known to influence height such as income and education, population density is negatively correlated with height among white men, but only marginally among white women. Similar analysis of Body Mass Index (BMI) also shows a negative correlation with population density after adjustment for income, education, and age for both sexes. Local economic conditions as measured by median income, unemployment rate or poverty rate do not have a strong correlation with height or weight after adjusting for individual income and education

Comparing Strategies for Estimating Constituency Opinion from National Survey Samples

Political scientists interested in estimating how public opinion varies by constituency have developed several strategies for supplementing limited constituency survey data with additional sources of information. We present two evaluation studies in the previously unexamined context of British constituency-level opinion: an external validation study of party vote share in the 2010 general election and a cross-validation of opinion toward the European Union. We find that most of the gains over direct estimation come from the inclusion of constituency-level predictors, which are also the easiest source of additional information to incorporate. Individual-level predictors combined with post-stratification particularly improve estimates from unrepresentative samples, and geographic local smoothing can compensate for weak constituency-level predictors. We argue that these findings are likely to be representative of applications of these methods where the number of constituencies is large

Measuring political positions from legislative speech

Existing approaches to measuring political disagreement from text data perform poorly except when applied to narrowly selected texts discussing the same issues and written in the same style. We demonstrate the first viable approach for estimating legislator-specific scores from the entire speech corpus of a legislature, while also producing extensive information about the evolution of speech polarization and politically loaded language. In the Irish Dail, we show that the dominant dimension of speech variation is government-opposition, with ministers more extreme on this dimension than backbenchers, and a second dimension distinguishing between the establishment and anti-establishment opposition parties. In the US Senate, we estimate a dimension that has moderate within-party correlations with scales based on roll-call votes and campaign donation patterns, however we observe greater overlap across parties in speech positions than roll call positions and partisan polarization in speeches varies more clearly in response to major political events

Can citizens guess how other citizens voted based on demographic characteristics?

How well do citizens understand the associations between social groups and political divisions in their societies? Previous research has indicated systematic biases in how the demographic composition of party supporters are perceived, but this need not imply that citizens misperceive the likely voting behavior of specific individuals. We report results from two experiments where subjects were provided with randomly selected demographic profiles of respondents to the 2017 British Election Study (BES) and then asked to assess either (1) which party that individual was likely to have voted for in the 2017 UK election or (2) whether that individual was likely to have voted Leave or Remain in the 2016 UK referendum on EU membership. We find that, despite substantial overconfidence in individual responses, on average citizens’ guesses broadly reflect the actual distribution of groups supporting the parties and referendum positions

The Variable Persuasiveness of Political Rhetoric

Which types of political rhetoric are most persuasive? Politicians make arguments that share common rhetorical elements, including metaphor, ad hominem attacks, appeals to expertise, moral appeals, and many others. However, political arguments are also highly multidimensional, making it difficult to assess the relative persuasive power of these elements. We report on a novel experimental design which assesses the relative persuasiveness of a large number of arguments that deploy a set of rhetorical elements to argue for and against proposals across a range of UK political issues. We find modest differences in the average effectiveness of rhetorical elements shared by many arguments, but also large variation in the persuasiveness of arguments of the same rhetorical type across issues. In addition to revealing that some argument-types are more effective than others in shaping public opinion, these results have important implications for the interpretation of survey-experimental studies in the field of political communication

Estimating vote-specific preferences from roll-call data using conditional autoregressive priors

Ideal point estimation in political science usually aims to reduce a matrix of votes to a small number of preference dimensions. We argue that taking a non-parametric perspective can yield measures that are more useful for some subsequent analyses. We propose a conditional autoregressive preference measurement model, which we use to generate case-specific preference estimates for US Supreme Court justices from 1946 to 2005. We show that the varying relative legal positions taken by justices across areas of law condition the opinion assignment strategy of the Chief Justice and the decisions of all justices as to whether to join the majority opinion. Unlike previous analyses that have made similar claims, using case-specific preference estimates enables us to hold constant the justices involved, providing stronger evidence that justices are strategically responsive to each others' relative positions on a case-by-case basis rather than simply their identities or average relative preferences

Decomposing Public Opinion Variation into Ideology, Idiosyncrasy, and Instability

We propose a method for decomposing variation in the issue preferences that US citizens express on surveys into three sources of variability that correspond to major threads in public opinion research. We find that, averaging across a set of high-profile US political issues, a single ideological dimension accounts for about 1/7 of opinion variation, individuals’ idiosyncratic preferences account for about 3/7, and response instability for the remaining 3/7. These shares vary substantially across issue types, and the average share attributable to ideology doubles when a second ideological dimension is permitted. We also find that (unidimensional) ideology accounts for almost twice as much response variation (and response instability is substantially lower) among respondents with high, rather than low, political knowledge. Our estimation strategy is based on an ordinal probit model with random effects and is applicable to other data sets that include repeated measurements of ordinal issue position data

Comparing Strategies for Estimating Constituency Opinion from National Survey Samples

Political scientists interested in estimating how public opinion varies by constituency have developed several strategies for supplementing limited constituency survey data with additional sources of information. We present two evaluation studies in the previously unexamined context of British constituency-level opinion: an external validation study of party vote share in the 2010 general election and a cross-validation of opinion toward the European Union. We find that most of the gains over direct estimation come from the inclusion of constituency-level predictors, which are also the easiest source of additional information to incorporate. Individual-level predictors combined with post-stratification particularly improve estimates from unrepresentative samples, and geographic local smoothing can compensate for weak constituency-level predictors. We argue that these findings are likely to be representative of applications of these methods where the number of constituencies is large

Combining national and constituency polling for forecasting

We describe a method for forecasting British general elections by combining national and constituency polling. We reconcile national and constituency estimates through a new swing model