In the Netherlands research has been performed on the Observational Method, aiming at a wider use of the method in the design of underground and infrastructural construction works. This paper summarizes the guideline that was output of the research, providing a clear definition, an overview of obstacles and pre-conditions, practical recommendations on how to make a safe design while using the p...

In this paper, Kolmogorov-Sinai entropy is studied using mathematical modeling of an observer $ Theta $. The relative entropy of a sub-$ sigma_Theta $-algebra having finite atoms is defined and then   the ergodic properties of relative  semi-dynamical systems are investigated.  Also,  a relative version of Kolmogorov-Sinai theorem  is given. Finally, it is proved  that the relative entropy of a...

OBJECTIVES Instead of evaluating one risk factor at a time, we illustrate the utility of "field-wide meta-analyses" in considering all available data on all putative risk factors of a disease simultaneously. STUDY DESIGN AND SETTING We identified studies on putative risk factors of pterygium (surfer's eye) in PubMed, EMBASE, and Web of Science. We mapped which factors were considered, reporte...

In this paper I investigate the nexus between life time utility (life satisfaction) and income predicted by the standard model of endogenous economic growth under different behavioral assumptions. The solution rationalizes why the empirical association between income and life satisfaction is approximately log-linear. I show that the solution is observationally equivalent when individuals compar...

In this paper we study a notion of operational equivalence for interaction nets, following the recent success of applying methods based on bisimulation to functional and object oriented programming languages. We set up notions of contextual equivalence and bisimilarity and show that they coincide. A coinduction principle then gives a simple and robust way of showing when two interaction nets ar...

We present a calculus inspired by K whose main features are: explicit process distribution and node interconnections, remote operations, process mobility and asynchronous communication through distributed tuple spaces. We first introduce a basic language where connections are reliable and immutable; then, we enrich it with two more advanced features for global computing, i.e. failures and d...

We compute the response of output to a monetary shock in a general equilibrium model in which firms set prices subject to a menu cost as well a costly observation of the state. We consider economies that are observationally equivalent with respect to the average frequency and size of price adjustments, and show that these economies respond differently to monetary shocks, depending on the size o...

In this paper it is shown how operational semantic methods may be naturally extended to encompass many of the concepts of denotational semantics. This work builds on the standard development of an operational semantics as an interpreter and operational equivalence. The key addition is an operational ordering on sets of terms. From properties of this ordering a closure construction directly yiel...

In this article I examine two mathematical definitions of observational equivalence, one proposed by Charlotte Werndl and based on manifest isomorphism, and the other based on Ornstein and Weiss’s ε-congruence. I argue, for two related reasons, that neither can function as a purely mathematical definition of observational equivalence. First, each definition permits of counterexamples; second, o...