Our goal is to investigate specification-based approaches to testing OO components. That is, given a class C and its specification, how do we test C to see if it meets its specification? Two important requirements that we impose on the testing approach are that it must not require access to the source code of the class under test; and that it should enable us to deal incrementally with derived ...

The operational definition of observational congruence in CCS and ACP can be split into two parts: one, the definition of an observational semantics (i.e. abstraction); and two, the definition of a strong congruence. In both cases this “separation of concerns” has been applied with abstraction that is implicitly “fair”. We define a novel (if obvious) observational semantics with no implicit “fa...

The Non Accelerating In‡ation Rate of Unemployment (NAIRU) is estimated for the post-stabilization period, as an unobserved stochastic variable, using state-of-the-art State Space Models. The NAIRU is identi...ed by a Phillips curve equation, and is assumed to follow a random walk. The basic model is augmented by an equation that captures the persistence of the unemployment gap. We also use the...