Tracking the Household Income of SSDI and SSI Applicants

Using panel data from the Survey of Income and Program Participation linked to Social Security Administration disability determination records we trace the pattern of household income and the sources of that income from 38 months prior to 39 months following application for Social Security Disability Insurance (SSDI) and Supplemental Security Insurance (SSI). We find that the average applicant’s labor earnings declines dramatically beginning six month before application but the average applicant’s household income drops much less dramatically both in the months just before or just after application and over the next three years, and does so even for those denied benefits. However, we also found substantial heterogeneity in household income outcomes in both the SSDI and SSI applicant population. Our quantile regressions suggest that higher income households experience greater percentage declines in their post-application income. Such results are consistent with the lower replacement rate for higher earners established in the SSDI program and the low absolute level of protection provided to all SSI applicants regardless of income prior to application.

U.S. v. Microsoft: Did Consumers Win?

U.S. v. Microsoft and the related state suit filed in 1998 appear finally to have concluded. In a unanimous en banc decision issued in late June 2004, the D.C. Circuit Court of Appeals rejected challenges to the remedies approved by the District Court in November 2002. The wave of follow-on private antitrust suits filed against Microsoft also appears to be subsiding. In this paper we review the remedies imposed in the United States, in terms of both their relationship to the violations found and their impact on consumer welfare. We conclude that the remedies addressed the violations ultimately found by the Court of Appeals (which were a subset of those found by the original district court and an even smaller subset of the violations alleged, both in court and in public discourse) and went beyond them in important ways. Thus, for those who believe that the courts were right in finding that some of Microsoft's actions harmed competition, the constraints placed on its behavior and the active, ongoing oversight by the Court and the plaintiffs provide useful protection against a recurrence of such harm. For those who believe that Microsoft should not have been found liable because of insufficient evidence of harm to consumers, the remedies may be unnecessary, but they avoided the serious potential damage to consumer welfare that was likely to accompany the main alternative proposals. The remedies actually imposed appear to have struck a reasonable balance between protecting consumers against the types of actions found illegal and harming consumers by unnecessarily restricting Microsoft's ability to compete.

Character decomposition of Potts model partition functions. II. Toroidal geometry

We extend our combinatorial approach of decomposing the partition function of the Potts model on finite two-dimensional lattices of size L x N to the case of toroidal boundary conditions. The elementary quantities in this decomposition are characters K\_{l,D} labelled by a number of bridges l=0,1,...,L and an irreducible representation D of the symmetric group S\_l. We develop an operational method of determining the amplitudes of the eigenvalues as well as some of their degeneracies.Comment: 27 pages, 4 figure

Characteristics of Sediments in the James River Estuary, Virginia

This report presents data on the physical and chemical characteristics of bottom sediments in the James River estuary, Virginia. The data were generated as part of a comprehensive study of sedimentation in which the initial objective was to broadly define the distribution of sediment properties

Conformal boundary loop models

We study a model of densely packed self-avoiding loops on the annulus, related to the Temperley Lieb algebra with an extra idempotent boundary generator. Four different weights are given to the loops, depending on their homotopy class and whether they touch the outer rim of the annulus. When the weight of a contractible bulk loop x = q + 1/q satisfies -2 < x <= 2, this model is conformally invariant for any real weight of the remaining three parameters. We classify the conformal boundary conditions and give exact expressions for the corresponding boundary scaling dimensions. The amplitudes with which the sectors with any prescribed number and types of non contractible loops appear in the full partition function Z are computed rigorously. Based on this, we write a number of identities involving Z which hold true for any finite size. When the weight of a contractible boundary loop y takes certain discrete values, y_r = [r+1]_q / [r]_q with r integer, other identities involving the standard characters K_{r,s} of the Virasoro algebra are established. The connection with Dirichlet and Neumann boundary conditions in the O(n) model is discussed in detail, and new scaling dimensions are derived. When q is a root of unity and y = y_r, exact connections with the A_m type RSOS model are made. These involve precise relations between the spectra of the loop and RSOS model transfer matrices, valid in finite size. Finally, the results where y=y_r are related to the theory of Temperley Lieb cabling.Comment: 28 pages, 19 figures, 2 tables. v2: added new section 3.2, amended figures 17-18, updated reference