I propose a new measure of common, time-varying tail risk for large cross sections of stock returns. Stock return tails are described by a power law in which the power law exponent is allowed to transition smoothly through time as a function of recent data. It is motivated by asset pricing theory and is estimable via quasi-maximum likelihood. Estimates indicate substantial time variation in sto...

In a distributed system, it is often important to detect the causal relationships between events, where event e1 is causally before event e2 if e1 happened before e2 and could possibly have aaected the occurrence of e2. In this paper we argue that it can be essential to security that a process determine, in the face of malicious attack, how two events are causally related. We formulate attacks ...

In this article, we present a particle filter (PF)-based track-before-detect (PF TBD) procedure for detection of extended objects whose shape is modeled by an ellipse. By incorporating of an existence variable and the target shape parameters into the state vector, the proposed algorithm performs joint estimation of the target presence/ absence, trajectory and shape parameters under unknown nuis...

a) Implications for the future of nongovernmental organization. International nongovernmental organizations are mentioned in none of the reports considered, with the exception of the SATCOM Report — a non-UN national body. Nongovernmental organizations are mentioned in passing in the Capacity Study but the references are so vague that it is not clear what sort of NGOs are meant or whether they ...

Abstract During the 1950s–1970s, there were three geodesy professors in Sweden. Before and after that period only such position was at KTH Stockholm. One triple proposed creation of Nordic Geodetic Commission, which realized 1953 still exists much same form as originally proposed.