Assessment of multiattribute utility functions is significantly simplified if it is possible to decompose the function into more manageable pieces. Utility independence is a powerful property that serves well for this purpose, but if it is not appropriate in a given situation, what options does the analyst have? We review some possibilities and propose a new independence assumption based on the...

In this work we show a general construction for transforming any chameleon hash function to a strongly unforgeable one-time signature scheme. Combined with the result of [Bellare and Ristov, PKC 2007], this also implies a general construction of strongly unforgeable one-time signatures from Σ-protocols in the standard model. Our results explain and unify several works in the literature which ei...

The existence of one-way functions (owf) is arguably the most important problem in computer theory. The article discusses and refines a number of concepts relevant to this problem. For instance, it gives the first combinatorial complete owf, i.e., a function which is one-way if any function is. There are surprisingly many subtleties in basic definitions. Some of these subtleties are discussed o...

Conditions are given under which a one-way function can be used safely in a programming language. The security proof involves showing that secrets cannot be leaked easily by any program meeting the conditions unless breaking the one-way function is easy. The result is applied to a password system where passwords are stored in a public file as images under a one-way function.1

A finite function f is a mapping of {1 , 2 ,. .. , m } into {1 , 2 ,. .. , m } ∪ { # } where # is a symbol to be thought of as ''undefined.'' This paper defines a measure M(f) of the difficulty of inverting a finite function f, which is given by M(f) = MIN    log 2 C(f) log 2 C(g) _ _________ : g an inverse of f    where C(f) is a circuit complexity measure of the difficulty of computing ...

In this paper, four new algorithms for improvements of MD5 and SHA-Keyed/Unkeyed MD5 and Keyed/Unkeyed SHA are proposed. We change the mode of ®xed retrieval of the parameters to that of dynamic retrieval of the parameters by applying a mapping between the index phrase and the parameter table. As shown in the experimental result, with 1% degradation of performance, comparing to the original alg...

This paper studies the design of cryptographic schemes that are secure even if implemented on untrusted machines that fall under adversarial control. For example, this includes machines that are infected by a software virus. We introduce a new cryptographic notion that we call a one-time computable pseudorandom function (PRF), which is a PRF FK(·) that can be evaluated on at most one input, eve...

Generic case complexity has originated about a decade ago in combinatorial group theory [10, 2]. This area has long computational traditions with many fundamental problems being algorithmic in nature. It has been shown that most computational problems in infinite group theory are recursively undecidable. However, it was also observed that decision algorithms, sometimes very naive ones, exist fo...

This paper derives the functional forms of multiattribute utility functions that lead to a maximum of one-switch change in preferences between any two uncertain and multiperiod cash flows as the decision maker’s wealth increases through constant annuity payments. We derive the general and continuous non-constant solutions of the corresponding functional equations. 2013 Elsevier Inc. All rights ...

Symmetry of information (in Kolmogorov complexity) is a concept that comes from formalizing the idea of how much information about a string y is contained in a string x. The situation is symmetric because it can be shown that the amount of information contained in the string y about the string x is almost exactly the same as that contained in x about y. In this paper we address symmetry of info...