We investigate the problem of de ning an approximation measure for functional dependencies (FDs). For xed sets of attributes, X and Y , an approximation measure is a function which maps relation instances to real numbers. The number to which an instance is mapped, intuitively, describes the strength of the dependency, X ! Y , in that instance. We de ne an approximation measure for FDs based on ...

For a finite lattice L, let EL denote the reflexive and transitive closure of the join-dependency relation on L, defined on the set J(L) of all join-irreducible elements of L. We characterize the relations of the form EL, as follows: Theorem. Let E be a quasi-ordering on a finite set P . Then the following conditions are equivalent: (i) There exists a finite lattice L such that 〈J(L),EL〉 is iso...

cities need good, participatory and effective policies and plans for development. urban development plans such as comprehensive plan are the most important tool for implementation of policies and plans. the effective implementation of city development plan requires high level documents such as spatial planning; good macro development plans policies, efficient urban management and public partici...

background: although extensive development of technology provides welfare and accessibility for families but it may be one of the threatening factors for them. the unique characteristics of internet such as availability and facility are useful, but over using for its exciting content cause to internet addiction between family members. the aim of this study was to explain the experiences of the ...

In Database Theory, Multivalued Dependencies are the main tool to define the Fourth Normal Form and, as such, their inference problem has been deeply studied; two related notions appearing in that study are a syntactical analog in propositional logic and a restriction that maintains to this logic the same relationship as Functional Dependencies do to Horn logic. We present semantic, lattice-the...

This paper explores commonalities and differences between Dachs, a variant of Dependency Grammar, and Lexical-Functional Grammar. Dachs is based on traditional linguistic insights, but on modern mathematical tools, aiming to integrate different knowledge systems (from syntax and semantics) via their coupling to an abstract syntactic primitive, the dependency relation. These knowledge systems co...

We develop a more general theory budgetary politics and examine its implications on a new dataset on US government expenditures from 1791 to 2010. We draw on three major approaches to budgeting: the decision-making theories, primarily incrementalism, and serial processing; the policy process models, basically extensions of punctuated equilibrium; and path dependency. We show that the incrementa...

The main claim of this paper is that causation, as commonly understood in the philosophical and psychological literature, is not fully expressed in natural language predicates. It neither matches the syntactic structure they project nor their lexical semantics. What a predicate can do is emulate causation by other means, albeit imperfectly. As a point of departure, we should provide a definitio...