Negotiating the Probabilistic Satisfaction of Temporal Logic Motion Specifications

We propose a human-supervised control synthesis method for a stochastic Dubins vehicle such that the probability of satisfying a specification given as a formula in a fragment of Probabilistic Computational Tree Logic (PCTL) over a set of environmental properties is maximized. Under some mild assumptions, we construct a finite approximation for the motion of the vehicle in the form of a tree-structured Markov Decision Process (MDP). We introduce an efficient algorithm, which exploits the tree structure of the MDP, for synthesizing a control policy that maximizes the probability of satisfaction. For the proposed PCTL fragment, we define the specification update rules that guarantee the increase (or decrease) of the satisfaction probability. We introduce an incremental algorithm for synthesizing an updated MDP control policy that reuses the initial solution. The initial specification can be updated, using the rules, until the supervisor is satisfied with both the updated specification and the corresponding satisfaction probability. We propose an offline and an online application of this method.Comment: 9 pages, 4 figures; The results in this paper were presented without proofs in IEEE/RSJ International Conference on Intelligent Robots and Systems November 3-7, 2013 at Tokyo Big Sight, Japa

2007: A Canadian Corporate Ownership Survey

This study documents a decline in the levels of corporate ownership concentration between 1996 and 2007. When compared to previous studies, the incidence of ownership stakes of 20% or larger has decreased form 60% to 41% of the total population of publicly listed Canadian firms. Regional disparities among provinces remain important. Ontario, Alberta, and British Columbia have the most widely-held firms, while Quebec and Atlantic Canada show the most concentrated corporate ownership patterns. The interpretation of these results requires a complex understanding of historical, demographic, cultural, political and institutional factors.Canada, corporate ownership, corporate governance, blockholder, ownership stake, ownership concentration