Targeted Advertising and Voter Turnout: An Experimental Study of the 2000 Presidential Election

Scholars disagree whether negative advertising demobilizes or stimulates the electorate. We use an experiment with over 10,200 eligible voters to evaluate the two leading hypotheses of negative political advertising. We extend the analysis to examine whether advertising differentially impacts the turnout of voter subpopulations depending on the advertisement痴 message. In the short term, we find no evidence that exposure to negative advertisements decreases turnout and little that suggests it increases turnout. Any effect appears to depend upon the message of the advertisement and the characteristics of the viewer. In the long term, we find little evidence that the information contained in the treatment groups・advertisements is sufficient to systematically alter turnout.

Nickel-hydrogen battery design for the Transporter Energy Storage Subsystem (TESS)

Information is given in viewgraph form on nickel hydrogen battery design for the transporter energy storage subsystem (TESS). Information is given on use in the Space Station Freedom, the launch configuration, use in the Mobile Servicing Center, battery design requirements, TESS subassembley design, proof of principle testing of a 6-cell battery, possible downsizing of TESS to support the Mobile Rocket Servicer Base System (MBS) redesign, TESS output capacity, and cell testing

Replication data for: An Experimental Study of the 2000 Presidential Election

Replication data and code forthcoming Scholars disagree whether negative advertising demobilizes or stimulates the electorate. We use an experiment with over 10,200 eligible voters to evaluate the two leading hypotheses of negative political advertising. We extend the analysis to examine whether advertising differentially impacts the turnout of voter subpopulations depending on the advertisement’s message. In the short term, we find no evidence that exposure to negative adv ertisements decreases turnout and little that suggests it increases turnout. Any effect appears to depend upon the message of the advertisement and the characteristics of the viewer. In the long term, we find little evidence that the information contained in the treatment groups’ advertisements is sufficient to systematically alter turnou

Replication data for: Measuring Significant Legislation, 1877 to 1948

Replication data and code forthcoming In this study, we provide a measure of legislative output that can be used to characterize outcomes of the lawmaking process across time. We summarize our efforts to identify the 21,741 public statutes passed between 1877 (45th Congress) and 1948 (80th Congress). In so doing we collect both statute-level descriptive information and the assessments of several scholars and chroniclers who identify enactments of note during this time period. Using this massive data collection we can characterize and assess congressional lawmaking activity across a period spanning the Populist, Progressive, and New Deal Eras as well as the two world war

Replication data for: Measuring Legislative Accomplishment, 1877-1994

Replication data and code forthcoming. In the meanwhile, please contact the author for access to the data Understanding the dynamics of lawmaking in the U.S. is at the center of the study of American politics. A fundamental obstacle to progress in this pursuit is the lack of direct measures of policy output, especially for the period prior to 1946. The lack of direct measures of legislative accomplishment makes it difficult to assess the performance of our political sy stem. We provide a new measure of legislative significance and accomplishment. Specifically, we demonstrate how item response theory can be combined with a new dataset that contains every public statute enacted between 1877 and 1994 to estimate "legislative importance" across time. Although the resulting estimates provide a new opportunity for scholars interested in analyzing policymaking in the U.S. since 1877, the methodology we present is not restricted to Congress, the U.S., or lawmaking

Seabed mapping and characterization of sediment variability using the usSEABED data base

Author Posting. © The Author(s), 2007. This is the author's version of the work. It is posted here by permission of Elsevier B.V. for personal use, not for redistribution. The definitive version was published in Continental Shelf Research 28 (2008): 614-633, doi:10.1016/j.csr.2007.11.011.We present a methodology for statistical analysis of randomly-located marine sediment point data, and apply it to the U.S. continental shelf portions of usSEABED mean grain size records. The usSEABED database, like many modern, large environmental datasets, is heterogeneous and interdisciplinary. We statistically test the database as a source of mean grain size data, and from it provide a first examination of regional seafloor sediment variability across the entire US continental shelf. Data derived from laboratory analyses (“extracted”) and from word-based descriptions (“parsed”) are treated separately, and they are compared statistically and deterministically. Data records are selected for spatial analysis by their location within sample regions: polygonal areas defined in ArcGIS chosen by geography, water depth, and data sufficiency. We derive isotropic, binned semivariograms from the data, and invert these for estimates of noise variance, field variance, and decorrelation distance. The highly erratic nature of the semivariograms is a result both of the random locations of the data and of the high level of data uncertainty (noise). This decorrelates the data covariance matrix for the inversion, and largely prevents robust estimation of the fractal dimension. Our comparison of the extracted and parsed mean grain size data demonstrates important differences between the two. In particular, extracted measurements generally produce finer mean grain sizes, lower noise variance, and lower field variance than parsed values. Such relationships can be used to derive a regionallydependent conversion factor between the two. Our analysis of sample regions on the U.S. continental shelf revealed considerable geographic variability in the estimated statistical parameters of field variance and decorrelation distance. Some regional relationships are evident, and overall there is a tendency for field variance to be higher where the average mean grain size is finer grained. Surprisingly, parsed and extracted noise magnitudes correlate with each other, which may indicate that some portion of the data variability that we identify as “noise” is caused by real grain size variability at very short scales. Our analyses demonstrate that by applying a bias-correction proxy, usSEABED data can be used to generate reliable interpolated maps of regional mean grain size and sediment character.The authors thank the Office of Naval Research for support under grants N00014-05-1-0079 (JAG) and N00014-05-1-0080 (CJJ), and the USGS/Coastal and Marine Geology Program (SJW)