Measuring Inter-judge Sentencing Disparity Before and After the Federal Sentencing Guidelines

This paper evaluates the impact of the Federal Sentencing Guidelines on inter-judge sentencing disparity, which is defined as the differences in average nominal prison sentence lengths for comparable caseloads assigned to different judges. This disparity is measured as the dispersion of a random effect in a zero-inflated negative binomial model. The results show that the expected difference between two typical judges in the average sentence length was about 17 percent (or 4.9 months) in 1986-87 prior to the Guidelines, and fell to about 11 percent (or 3.9 months) from 1988-93 during the early years of the Guidelines. We have not sought to measure the effect of parole in the pre-Guidelines period, other sources of disparity such as prosecutorial discretion, or the proportionality of punishment under the Guidelines as compared with the pre-Guidelines era.Interjudge sentencing disparity, Federal Sentencing Guidelines Zero-inflated negative binomial random effect model

Ice in Clouds Experiment—Layer Clouds. Part I: Ice Growth Rates Derived from Lenticular Wave Cloud Penetrations

Lenticular wave clouds are used as a natural laboratory to estimate the linear and mass growth rates of ice particles at temperatures from -20° to -32°C and to characterize the apparent rate of ice nucleation at water saturation at a nearly constant temperature. Data are acquired from 139 liquid cloud penetrations flown approximately along or against the wind direction. A mean linear ice growth rate of about 1.4 µm s⁻¹, relatively independent of particle size (in the range 100-400 µm) and temperature is deduced. Using the particle size distributions measured along the wind direction, the rate of increase in the ice water content (I WC) is calculated from the measured particle size distributions using theory and from those distributions by assuming different ice particle densities; the IWC is too small to be measured. Very low ice effective densities, <0.1 g cm⁻³, are needed to account for the observed rate of increase in the [WC and the unexpectedly high linear growth rate. Using data from multiple penetrations through a narrow (along wind) and thin wave cloud with relatively flat airflow streamlines, growth rate calculations are used to estimate where the ice particles originate and whether the ice is nucleated in a narrow band or over an extended period of time. The calculations are consistent with the expectation that the ice formation occurs near the leading cloud edge, presumably through a condensation-freezing process. The observed ice concentration increase along the wind is more likely due to a variation in ice growth rates than to prolonged ice nucleation.Keywords: Probes, Aerosols, Microphysical properties, Nuclei, Cirrus, Liquid water content, Snow crystals, Nucleation, Tunnel, Counterflow virtual impacto

The Future of American Sentencing: A National Roundtable on Blakely

In the wake of the dramatic Supreme Court decision in Blakely v. Washington, Stanford Law School convened an assembly of the most eminent academic and professional sentencing experts in the country to jointly assess the meaning of the decision and its implications for federal and state sentencing reform. The event took place on October 8 and 9, just a few months after Blakely came down and the very week that the Supreme Court heard the arguments in United States v. Booker and United States v. Fanfan, the cases that will test Blakely\u27s application to the Federal Sentencing Guidelines. Thus the Roundtable offered these experts an intellectual breathing space at a crucial point in American criminal law. The event was built around six sessions, with shifting panels of participants doing brief presentations on the subject of the session, and with others then joining in the discussion. We are pleased that FSR is able to publish this version of the proceedings of the event-a condensed and edited transcript of the sessions

Modeling Approaches in Avian Conservation and the Role of Field Biologists

This review grew out of our realization that models play an increasingly important role in conservation but are rarely used in the research of most avian biologists. Modelers are creating models that are more complex and mechanistic and that can incorporate more of the knowledge acquired by field biologists. Such models require field biologists to provide more specific information, larger sample sizes, and sometimes new kinds of data, such as habitat-specific demography and dispersal information. Field biologists need to support model development by testing key model assumptions and validating models. The best conservation decisions will occur where cooperative interaction enables field biologists, modelers, statisticians, and managers to contribute effectively. We begin by discussing the general form of ecological models- heuristic or mechanistic, scientific or statistical- and then highlight the structure, strengths, weaknesses, and applications of six types of models commonly used in avian conservation: (1) deterministic single population matrix models, (2) stochastic population viability analysis (PVA) models for single populations, (3) metapopulation models, (4) spatially explicit models, (5) genetic models, and (6) species distribution models. We end by considering the intelligent use of models in decision- making, which requires understanding their unique attributes, determining whether the assumptions that underlie the structure are valid, and testing the ability of the model to predict the future correctly