Hiding variables when decomposing specifications into GR(1) contracts

We propose a method for eliminating variables from component specifications during the decomposition of GR(1) properties into contracts. The variables that can be eliminated are identified by parameterizing the communication architecture to investigate the dependence of realizability on the availability of information. We prove that the selected variables can be hidden from other components, while still expressing the resulting specification as a game with full information with respect to the remaining variables. The values of other variables need not be known all the time, so we hide them for part of the time, thus reducing the amount of information that needs to be communicated between components. We improve on our previous results on algorithmic decomposition of GR(1) properties, and prove existence of decompositions in the full information case. We use semantic methods of computation based on binary decision diagrams. To recover the constructed specifications so that humans can read them, we implement exact symbolic minimal covering over the lattice of integer orthotopes, thus deriving minimal formulae in disjunctive normal form over integer variable intervals

An analysis of the length of labour and financial contracts: a study for Spain.

This study investigates the connection between the duration of financial contracts and that of labour contracts. Workers with long-term contracts have incentives to invest in training. This makes them attractive to the entrepreneur. Furthermore, this behaviour will be reinforced if financial contracts are long-term, because it reduces the probability of an early liquidation as well as the dismissal of trained workers. As a conclusion, significant increases in the length of financing contracts should be accompanied by corresponding increases in the length of labour contracts. Support for this theoretical contention is found by testing it on a dataset composed of Spanish manufacturing firms for the period 1991–2000.

Enriching OCL Using Observational Mu-Calculus

Abstract. The Object Constraint Language is a textual specificatio