Differential Privacy for the Analyst via Private Equilibrium Computation

We give new mechanisms for answering exponentially many queries from multiple analysts on a private database, while protecting differential privacy both for the individuals in the database and for the analysts. That is, our mechanism's answer to each query is nearly insensitive to changes in the queries asked by other analysts. Our mechanism is the first to offer differential privacy on the joint distribution over analysts' answers, providing privacy for data analysts even if the other data analysts collude or register multiple accounts. In some settings, we are able to achieve nearly optimal error rates (even compared to mechanisms which do not offer analyst privacy), and we are able to extend our techniques to handle non-linear queries. Our analysis is based on a novel view of the private query-release problem as a two-player zero-sum game, which may be of independent interest

Black Hole Attractors and Pure Spinors

We construct black hole attractor solutions for a wide class of N=2 compactifications. The analysis is carried out in ten dimensions and makes crucial use of pure spinor techniques. This formalism can accommodate non-Kaehler manifolds as well as compactifications with flux, in addition to the usual Calabi-Yau case. At the attractor point, the charges fix the moduli according to sum_k f_k = Im(C Phi), where Phi is a pure spinor of odd (even) chirality in IIB (A). For IIB on a Calabi-Yau, Phi=Omega and the equation reduces to the usual one. Methods in generalized complex geometry can be used to study solutions to the attractor equation.Comment: 26 page

Youth violence: A study of moral panics in terms of schismogenic loops.

This study examines the problem of the moral panic over youth violence focusing on how these phenomena emerge and eventually subside. Utilizing data from the 1995 Toronto Star the evolution of a moral panic is outlined and a multi-causal model is employed to show the dynamics of the moral panic. Findings indicate that three main article types contributed to the escalation and de-escalation of the moral panic. These were Violent Youth Crime Articles, Political Articles, and Filler Articles. Violent youth crime articles initially fueled the beginning of the panic. Then political articles stressing harsher penalties emerged to create even more public fear and escalate the panic. When there was a lack of violent youth crime articles, fillers supporting claims that violence was worsening occupied the void to further ensure the continuation of the panic. However, without violent youth crime articles, the panic was unable to sustain itself solely on fillers and political articles. As fillers and political articles began to shift towards a softer, less punitive approach to youth violence, the panic eventually diminished. By applying key concepts developed in the schismogenic model this study demonstrates the existence of escalation and de-escalation loops that can create and reduce a panic. The loops discovered in the findings do not indicate the pattern of loops all moral panics will follow. The dynamic nature of the model dictates that different panics will operate on different sets of loops. These findings suggest that simplistic and single-factor approaches to moral panics are insufficient because they fail to account for the multiple pathways that appear to operate in these events.Dept. of Sociology and Anthropology. Paper copy at Leddy Library: Theses & Major Papers - Basement, West Bldg. / Call Number: Thesis1998 .H78. Source: Masters Abstracts International, Volume: 39-02, page: 0412. Adviser: Stephen Baron. Thesis (M.A.)--University of Windsor (Canada), 1998

Volume Stabilization and the Origin of the Inflaton Shift Symmetry in String Theory

The main problem of inflation in string theory is finding the models with a flat potential, consistent with stabilization of the volume of the compactified space. This can be achieved in the theories where the potential has (an approximate) shift symmetry in the inflaton direction. We will identify a class of models where the shift symmetry uniquely follows from the underlying mathematical structure of the theory. It is related to the symmetry properties of the corresponding coset space and the period matrix of special geometry, which shows how the gauge coupling depends on the volume and the position of the branes. In particular, for type IIB string theory on K3xT^2/Z with D3 or D7 moduli belonging to vector multiplets, the shift symmetry is a part of SO(2,2+n) symmetry of the coset space [SU(1,1)/ U(1)]x[SO(2,2+n)/(SO(2)x SO(2+n)]. The absence of a prepotential, specific for the stringy version of supergravity, plays a prominent role in this construction, which may provide a viable mechanism for the accelerated expansion and inflation in the early universe.Comment: 12 page

An Archaeometallurgical Explanation for the Disappearance of Egyptian and Near Eastern Cobalt-Blue Glass at the end of the Late Bronze Age

A recent compositional study of Egyptian cobalt-blue glass from museum collections in Japan (18th Dynasty) and from the site of Dahshur (18th and 19th-20th Dynasties) concluded that a new source of cobalt was exploited for the later Dahshur glass, thereby suggesting that glass production continued into the Ramesside period (Abe et al. 2012). It is shown in the current article that some of this 18th Dynasty glass and the majority of the 19th-20th Dynasty glass had been recycled, not only supporting the general consensus that glass production virtually disappeared by 1250 BC, but that the cobalt source did not necessarily change. It is further proposed, however, that the generally accepted cobalt source for Egyptian glass was not the alum deposits of Egypt's Western Desert, but derived from cobaltiferous siliceous ores, possibly from central Iran. Re-analysis of the compositions of cobalt-blue glass frit found at Amarna, as well as Egyptian and Mesopotamian glass, suggests that the cobalt colourant was a by-product of silver extraction from these ores and can therefore be considered as a concentrated cobalt glass slag, which travelled in the form of a frit to glass producers who added it to locally derived base glasses and/or their precursors. Experiments conducted on ore containing cobalt-nickel arsenides with native silver demonstrate that not only can silver be extracted and that concentrated cobalt glass can be produced simply by adding a flux, but that some components of the ore partition preferentially into the silver or the glass slag, thereby weakening their associations with the other components in archaeological glass. Treating the cobalt-blue colourant as a slag composed of the gangue of a smelting system provides an explanation for the unique elevated levels of alumina and lower levels of potash found in cobalt-blue glasses, as well as providing an explanation for the cessation of cobalt exploitation at the end of the Late Bronze Age. It is suggested that the exhaustion of native silver and siliceous silver ore deposits during the Bronze Age, with argentiferous lead ores becoming the main source of silver, depleted the amount of cobalt available, thereby reducing the amount of glass produced which, in turn, led to increases in recycling during the New Kingdom period.</jats:p

Generating Acoustic Diffuser Arrays with Shape Grammars

This paper presents research on a rule-based approach to designing creative acoustic diffuser arrays. A shape grammar-influenced design method is specified that uses shape rules to recursively design arrays of quadratic residue diffusers (QRD) in ways that are neither mechanical nor deterministic

Coping with family structure in genome-wide association studies: a comparative evaluation

In this paper, a fully statistical investigation of the control of family structure as random effects is analyzed and discussed, using both the genome-wide association studies (GWAS) data and simulated data. Three modeling strategies are proposed and the analysis results suggest the hybrid use of results from all possible models should be combined in practice