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Automated Whitebox Fuzz Testing
"... Fuzz testing is an effective technique for finding security vulnerabilities in software. Traditionally, fuzz testing tools apply random mutations to wellformed inputs of a program and test the resulting values. We present an alternative whitebox fuzz testing approach inspired by recent advances in ..."
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Cited by 292 (23 self)
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Fuzz testing is an effective technique for finding security vulnerabilities in software. Traditionally, fuzz testing tools apply random mutations to wellformed inputs of a program and test the resulting values. We present an alternative whitebox fuzz testing approach inspired by recent advances in symbolic execution and dynamic test generation. Our approach records an actual run of the program under test on a wellformed input, symbolically evaluates the recorded trace, and gathers constraints on inputs capturing how the program uses these. The collected constraints are then negated one by one and solved with a constraint solver, producing new inputs that exercise different control paths in the program. This process is repeated with the help of a codecoverage maximizing heuristic designed to find defects as fast as possible. We have implemented this algorithm in SAGE (Scalable, Automated, Guided Execution), a new tool employing x86 instructionlevel tracing and emulation for whitebox fuzzing of arbitrary filereading Windows applications. We describe key optimizations needed to make dynamic test generation scale to large input files and long execution traces with hundreds of millions of instructions. We then present detailed experiments with several Windows applications. Notably, without any formatspecific knowledge, SAGE detects the MS07017 ANI vulnerability, which was missed by extensive blackbox fuzzing and static analysis tools. Furthermore, while still in an early stage of development, SAGE has already discovered 30+ new bugs in large shipped Windows applications including image processors, media players, and file decoders. Several of these bugs are potentially exploitable memory access violations.
Analyzing Developmental Trajectories: A Semiparametric, GroupBased Approach
 Psychological Methods
, 1999
"... A developmental trajectory describes the course of a behavior over age or time. A groupbased method for identifying distinctive groups of individual trajectories within the population and for profiling the characteristics of group members is demonstrated. Such clusters might include groups of & ..."
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Cited by 216 (11 self)
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A developmental trajectory describes the course of a behavior over age or time. A groupbased method for identifying distinctive groups of individual trajectories within the population and for profiling the characteristics of group members is demonstrated. Such clusters might include groups of "increasers. " "decreasers," and "no changers. " Suitably defined probability distributions are used to handle 3 data types—count, binary, and psychometric scale data. Four capabilities are demonstrated: (a) the capability to identify rather than assume distinctive groups of trajectories, (b) the capability to estimate the proportion of the population following each such trajectory group, (c) the capability to relate group membership probability to individual characteristics and circumstances, and (d) the capability to use the group membership probabilities for various other purposes such as creating profiles of group members. Over the past decade, major advances have been made in methodology for analyzing individuallevel developmental trajectories. The two main branches of methodology are hierarchical modeling (Bryk &
Some exact results on tachyon condensation in string field theory
 JHEP
"... The study of open string tachyon condensation in string field theory can be drastically simplified by making an appropriate choice of coordinates on the space of string fields. We show that a very natural coordinate system is suggested by the connection between the worldsheet renormalization group a ..."
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Cited by 190 (8 self)
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The study of open string tachyon condensation in string field theory can be drastically simplified by making an appropriate choice of coordinates on the space of string fields. We show that a very natural coordinate system is suggested by the connection between the worldsheet renormalization group and spacetime physics. In this system only one field, the tachyon, condenses while all other fields have vanishing expectation values. These coordinates are also wellsuited to the study of Dbranes as solitons. We use them to show that the tension of the D25brane is cancelled by tachyon condensation and compute exactly the profiles and tensions of lower dimensional Dbranes. September
Communication of emotions in vocal expression and music performance: Different channels, same code? Psychol
 Bull
, 2003
"... Many authors have speculated about a close relationship between vocal expression of emotions and musical expression of emotions, but evidence bearing on this relationship has unfortunately been lacking. This review of 104 studies of vocal expression and 41 studies of music performance reveals simila ..."
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Cited by 182 (12 self)
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Many authors have speculated about a close relationship between vocal expression of emotions and musical expression of emotions, but evidence bearing on this relationship has unfortunately been lacking. This review of 104 studies of vocal expression and 41 studies of music performance reveals similarities between the 2 channels concerning (a) the accuracy with which discrete emotions were communicated to listeners and (b) the emotionspecific patterns of acoustic cues used to communicate each emotion. The patterns are generally consistent with K. R. Scherer’s (1986) theoretical predictions. The results can explain why music is perceived as expressive of emotion, and they are consistent with an evolutionary perspective on vocal expression of emotions. Discussion focuses on theoretical accounts and directions for future research. Music: Breathing of statues. Perhaps: Stillness of pictures. You speech, where speeches end. You time, vertically poised on the courses of vanishing hearts.
Can Relationship Banking Survive Competition
 Journal of Finance
, 1999
"... How will banks evolve as competition increases from other banks and from the capital market? Will banks become more like capital market underwriters and offer passive transaction loans or return to their roots as relationship lending experts? These are the questions we address. Our key result is tha ..."
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Cited by 179 (14 self)
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How will banks evolve as competition increases from other banks and from the capital market? Will banks become more like capital market underwriters and offer passive transaction loans or return to their roots as relationship lending experts? These are the questions we address. Our key result is that as interbank competition increases, banks make more relationship loans, but each has lower added value for borrowers. Capital market competition reduces relationship lending ~and bank lending shrinks!, but each relationship loan has greater added value for borrowers. In both cases, welfare increases for some borrowers but not necessarily for all. RAPID CHANGES IN FINANCIAL SERVICES ARE threatening commercial banks. In the United States, mutual funds such as Fidelity and Merrill Lynch compete for banks ’ core deposits. Investment banks, armed with a variety of financial market innovations, challenge banks ’ traditional lending products. Banks also find themselves in greater competition with one another as globalization
Compressive Sensing and Structured Random Matrices
 RADON SERIES COMP. APPL. MATH XX, 1–95 © DE GRUYTER 20YY
"... These notes give a mathematical introduction to compressive sensing focusing on recovery using ℓ1minimization and structured random matrices. An emphasis is put on techniques for proving probabilistic estimates for condition numbers of structured random matrices. Estimates of this type are key to ..."
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Cited by 162 (19 self)
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These notes give a mathematical introduction to compressive sensing focusing on recovery using ℓ1minimization and structured random matrices. An emphasis is put on techniques for proving probabilistic estimates for condition numbers of structured random matrices. Estimates of this type are key to providing conditions that ensure exact or approximate recovery of sparse vectors using ℓ1minimization.
The exact superconformal Rsymmetry maximizes a,” Nucl. Phys
 Sahakyan, “Central charges and U(1)R symmetries in N = 1 super Yang Mills,” JHEP 11 (2003) 013, hepth/0308071
"... An exact and general solution is presented for a previously open problem. We show that the superconformal Rsymmetry of any 4d SCFT is exactly and uniquely determined by a maximization principle: it is the Rsymmetry, among all possibilities, which (locally) maximizes the combination of ’t Hooft ano ..."
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Cited by 154 (15 self)
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An exact and general solution is presented for a previously open problem. We show that the superconformal Rsymmetry of any 4d SCFT is exactly and uniquely determined by a maximization principle: it is the Rsymmetry, among all possibilities, which (locally) maximizes the combination of ’t Hooft anomalies atrial(R) ≡ (9TrR3 − 3TrR)/32. The maximal value of atrial is then, by a result of Anselmi et. al., the central charge a of the SCFT. Our atrial maximization principle almost immediately ensures that the central charge a decreases upon any RG flow, since relevant deformations force atrial to be maximized over a subset of the previously possible Rsymmetries. Using atrial maximization, we find the exact superconformal Rsymmetry (and thus the exact anomalous dimensions of all chiral operators) in a variety of previously mysterious 4d N = 1 SCFTs. As a check, we verify that our exact results reproduce the perturbative anomalous dimensions in all perturbatively accessible RG fixed points. April
Lectures on 2D YangMills Theory, Equivariant Cohomology and Topological Field Theories
, 1996
"... These are expository lectures reviewing (1) recent developments in twodimensional YangMills theory and (2) the construction of topological field theory Lagrangians. Topological field theory is discussed from the point of view of infinitedimensional differential geometry. We emphasize the unifying ..."
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Cited by 141 (11 self)
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These are expository lectures reviewing (1) recent developments in twodimensional YangMills theory and (2) the construction of topological field theory Lagrangians. Topological field theory is discussed from the point of view of infinitedimensional differential geometry. We emphasize the unifying role of equivariant cohomology both as the underlying principle in the formulation of BRST transformation laws and as a central concept in the geometrical interpretation of topological field theory path integrals.
Flexible Discriminant Analysis by Optimal Scoring
 JOURNAL OF THE AMERICAN STATISTICAL ASSOCIATION
, 1993
"... Fisher's linear discriminant analysis is a valuable tool for multigroup classification. With a large number of predictors, one can nd a reduced number of discriminant coordinate functions that are "optimal" for separating the groups. With two such functions one can produce a classific ..."
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Cited by 139 (12 self)
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Fisher's linear discriminant analysis is a valuable tool for multigroup classification. With a large number of predictors, one can nd a reduced number of discriminant coordinate functions that are "optimal" for separating the groups. With two such functions one can produce a classification map that partitions the reduced space into regions that are identified with group membership, and the decision boundaries are linear. This paper is about richer nonlinear classification schemes. Linear discriminant analysis is equivalent to multiresponse linear regression using optimal scorings to represent the groups. We obtain nonparametric versions of discriminant analysis by replacing linear regression by any nonparametric regression method. In this way, any multiresponse regression technique (such as MARS or neural networks) can be postprocessed to improve their classification performence.
Results 1  10
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3,567