bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Honolulu posttraumatic stress disorder stimulus set
Authors: Chemtob Claude M. , Roitblat Herbert L. , Hamada Roger S. , Carlson John G. , Muraoka Miles Y. , Bauer Gordon B. 
Published: June 2007

AbstractWe present word and picture stimuli constituting a validated stimulus set appropriate for cognitive investigations of posttraumatic stress disorder (PTSD). Combat related and neutral words and pictures were rated by Vietnam veterans with PTSD and by three comparison groups along four dimensions: unpleasantness, Vietnam relevance, stressfulness, and memorability. There were distinctive patterns of responses by the PTSD group which efficiently discriminated the individuals in this group from those in the control groups. These stimuli have the potential to be developed as a diagnostic instrument.
Weak Forms of the Axiom of Choice and the Generalized Continuum Hypothesis
Authors: Rubin Arthur L. , Rubin Jean E. 
Published: June 2007

AbstractIn this paper we study some statements similar to the Partition Principle and the Trichotomy. We prove some relationships between these statements, the Axiom of Choice, and the Generalized Continuum Hypothesis. We also prove some independence results. MSC: 03E25, 03E50, 04A25, 04A50.
How to develop Proof‐Theoretic Ordinal Functions on the basis of admissible ordinals
Authors: Rathjen Michael 
Published: June 2007

AbstractIn ordinal analysis of impredicative theories so‐called collapsing functions are of central importance. Unfortunately, the definition procedure of these functions makes essential use of uncountable cardinals whereas the notation system that they call into being corresponds to a recursive ordinal. It has long been claimed that, instead, one should manage to develop such functions directly on the basis of admissible ordinals. This paper is meant to show how this can be done. Interpreting the collapsing functions as operating directly on admissible sets also renders a new and perspicuous approach to well‐ordering proofs possible. MSC: 03F15, 03F35.
Isols and maximal intersecting classes
Authors: Dekker Jacob C. E. 
Published: June 2007

AbstractIn transfinite arithmetic 2n is defined as the cardinality of the family of all subsets of some set v with cardinality n. However, in the arithmetic of recursive equivalence types (RETs) 2N is defined as the RET of the family of all finite subsets of some set v of nonnegative integers with RET N. Suppose v is a nonempty set. S is a class over v, if S consists of finite subsets of v and has v as its union. Such a class is an intersecting class (IC) over v, if every two members of S have a nonempty intersection. An IC over v is called a maximal IC (MIC), if it is not properly included in any IC over v. It is known and readily proved that every MIC over a finite set v of cardinality n ≥ 1 has cardinality 2n‐1. In order to generalize this result we introduce the notion of an ω‐MIC over v. This is an effective analogue ot the notion of an MIC over v such that a class over a finite set v is an ω‐MIC iff it is an MIC. We then prove that every ω‐MIC over an isolated set v of RET N ≥ 1 has RET 2N‐1. This is a generalization, for while there only are χ0 finite sets, there are ϰ isolated sets, where c denotes the cardinality of the continuum, namely all the finite sets and the c immune sets. MSC: 03D50.
La connaissance commune en logique modale
Authors: Lismont Luc 
Published: June 2007

AbstractThe problem of Common Knowledge will be considered in two classes of models: a class K.* of Kripke models and a class S of Scott models. Two modal logic systems will be defined. Those systems, KC and MC, include an axiomatisation of Common Knowledge. We prove determination of each system by the corresponding class of models. MSC: 03B45, 68T25.
A formalization of Sambins's normalization for GL
Authors: Haeusler Edward Hermann , Pereira Luiz Carlos 
Published: June 2007

AbstractSambin [6] proved the normalization theorem (Hauptsatz) for GL, the modal logic of provability, in a sequent calculus version called by him GLS. His proof does not take into account the concept of reduction, commonly used in normalization proofs. Bellini [1], on the other hand, gave a normalization proof for GL using reductions. Indeed, Sambin's proof is a decision procedure which builds cut‐free proofs. In this work we formalize this procedure as a recursive function and prove its recursiveness in an arithmetically formalizable way, concluding that the normalization of GL can be formalized in PA. MSC: 03F05, 03B35, 03B45.
Seperating the intrinsic complexity and the derivational complexity of the word problem for finitely presented groups
Authors: Cohen Daniel E. , Madlener Klaus , Otto Friedrich 
Published: June 2007

AbstractA pseudo‐natural algorithm for the word problem of a finitely presented group is an algorithm which not only tells us whether or not a word w equals 1 in the group but also gives a derivation of 1 from w when w equals 1. In [13], [14] Madlener and Otto show that, if we measure complexity of a primitive recursive algorithm by its level in the Grzegorczyk hierarchy, there are groups in which a pseudo‐natural algorithm is arbitrarily more complicated than an algorithm which simply solves the word problem. In a given group the lowest degree of complexity that can be realised by a pseudo‐natural algorithm is essentially the derivational complexity of that group. Thus the result separates the derivational complexity of the word problem of a finitely presented group from its intrinsic complexity. The proof given in [13] involves the construction of a finitely presented group G from a Turing machine T such that the intrinsic complexity of the word problem for G reflects the complexity of the halting problem of T, while the derivational complexity of the word problem for G reflects the runtime complexity of T. The proof of one of the crucial lemmas in [13] is only sketched, and part of the purpose of this paper is to give the full details of this proof. We will also obtain a variant of their proof, using modular machines rather than Turing machines. As for several other results, this simplifies the proofs considerably. MSC: 03D40, 20F10.
Computable limits and colimits in categories of partial enumerated sets
Authors: Orlicki Andrzej 
Published: June 2007

AbstractComputable limits and colimits are “recursive counterparts” of the suitable classical concepts from category theory. We present mainly some interesting problems related to computable products. Moreover, some “computable counterparts” of well‐known classical facts from category theory are given. MSC: 03D45, 18A30.
On Wainer's notation for a minimal subrecursive inaccessible ordinal
Authors: Kadota Noriya 
Published: June 2007

AbstractWe show the following results on Wainer's notation for a minimal subrecursive inaccessible ordinal τ: First, we give a constructive proof of the collapsing theorem. Secondly, we prove that the slow‐growing hierarchy and the fast‐growing hierarchy up to τ have elementary properties on increase and domination, which completes Wainer's proof that τ is a minimal subrecursive inaccessible. Our results are obtained by showing a strong normalization theorem for the term structure of the notation. MSC: 03D20, 03F15.
A boolean transfer principle from L*‐Algebras to AL*‐Algebras
Authors: Nishimura Hirokazu 
Published: June 2007

AbstractJust as Kaplansky [4] has introduced the notion of an AW*‐module as a generalization of a complex Hilbert space, we introduce the notion of an AL*‐algebra, which is a generalization of that of an L*‐algebra invented by Schue [9, 10]. By using Boolean valued methods developed by Ozawa [6–8], Takeuti [11–13] and others, we establish its basic properties including a fundamental structure theorem. This paper should be regarded as a continuation or our previous paper [5], the familiarity with which is presupposed. MSC: 03C90, 03E40, 17B65, 46L10.
Quasi‐Stone algebras
Authors: Sankappanavar Nalinaxi H. , Sankappanavar Hanamantagouda P. 
Published: June 2007

AbstractThe purpose of this paper is to define and investigate the new class of quasi‐Stone algebras (QSA's). Among other things we characterize the class of simple QSA's and the class of subdirectly irreducible QSA's. It follows from this characterization that the subdirectly irreducible QSA's form an elementary class and that the variety of QSA's is locally finite. Furthermore we prove that the lattice of subvarieties of QSA's is an (ω + 1)‐chain. MSC: 03G25, 06D16, 06E15.
A theory of sets with the negation of the axiom of infinity
Authors: Baratella Stefano , Ferro Ruggero 
Published: June 2007

AbstractIn this paper we introduce a theory of finite sets FST with a strong negation of the axiom of infinity asserting that every set is provably bijective with a natural number. We study in detail the role of the axioms of Power Set, Choice, Regularity in FST, pointing out the relative dependences or independences among them. FST is shown to be provably equivalent to a fragment of Alternative Set Theory. Furthermore, the introduction of FST is motivated in view of a non‐standard development. MSC: 03E30, 03E35.
Lebesgue Convergence Theorems and Reverse Mathematics
Authors: Yu Xiaokang 
Published: June 2007

AbstractConcepts of L1 space, integrable functions and integrals are formalized in weak subsystems of second order arithmetic. They are discussed especially in relation with the combinatorial principle WWKL (weak‐weak König's lemma and arithmetical comprehension. Lebesgue dominated convergence theorem is proved to be equivalent to arithmetical comprehension. A weak version of Lebesgue monotone convergence theorem is proved to be equivalent to weak‐weak König's lemma.Mathematics Subject Classification: 03F35.
Choices of Convenient Sets
Authors: Sochor Antonín 
Published: June 2007

AbstractProceeding in the theory with extensionality, comprehension for classes, existence of the empty set and the assumption the addition of one element to a set makes again a set (others usual set‐theoretical operations are not required) we show a week assumption which guarantees existence of a saturated elementary extension (with absolute ϵ) of the system of hereditarily finite sets.Mathematics Subject Classification: 03C62, 03C50, 03E70.
Complete, Recursively Enumerable Relations in Arithmetic
Authors: D'Agostino Giovanna , Magnago Mario 
Published: June 2007

AbstractUsing only propositional connectives and the provability predicate of a Σ1‐sound theory T containing Peano Arithmetic we define recursively enumerable relations that are complete for specific natural classes of relations, as the class of all r. e. relations, and the class of all strict partial orders. We apply these results to give representations of these classes in T by means of formulas.
Polygones
Authors: Mustafin Tolende G. , Poizat Bruno 
Published: June 2007

AbstractWe study the class of structures formed by all the polygons over a given monoid, which is equivalent to the study of the varieties in a language containing only unary functions. We collect and amplify previous results concerning their stability and superstability. Then we characterize the regular monoids for which all these polygons are ω‐stable; the question about the existence of a non regular monoid with this property is left open.
The changing structure of industrial relations in South Africa
Authors: Jones Robert A. 
Published: June 2007

AbstractThis is the second of two papers dealing tvith the emergence of black shop‐floor union power and the changing structure of industrial relations in South Africa. This paper examines union developments in the post‐Wiehahn era, The policies of the major union federations and the impact of the black unions' emphasis on shop‐floor bargaining. It is clear that the established unions, the State and individual company managements have been significantly affected by this development. The main issue in the near future is seen to be the dividing‐line between managerial prerogatives and worker‐participation.
The economics of diamond price movements
Authors: Ariovich G. 
Published: June 2007

AbstractDiamonds are traditionally classified into three different market segments —industrial, jewellery and investment. The empirical findings support the argument that diamond prices of these three group types respond differently to business cycles. Industrial diamond prices, especially those of natural stones, have been found to be influenced by the level of economic activity in general and the volume of manufacturing production in partiular. However, the price of synthetic diamonds, especially in grit form, have declined irrespective of the business cycle as a result of technological developments and the expansion of the market which enabled producers to gait scale advantages. Prices of jewellery diamonds have been found to be most highly correlated with disposable income. As could be expected, these price have also been found to be positively correlated with inflation rates and negatively correlated with real interest rates. Prices of investment diamonds have been found to be particularly sensitive to real interest rates, to the value of the exchange rates of the US dollar and, like other gems, to disposable income. The paper also describes and discusses the activity in various diamond markets and the business policy of De Beers, the ‘king’ of the rough diamonds.
Gold shares or gold bullion—which is the better investment?
Authors: Barr G. D. I. , Affleck‐Graves J. F. 
Published: June 2007

AbstractThis paper examines, from the standpoint of the US investor, the illative merits of an investment in gold bullion vis‐à‐vis South African gold shares. Markowitz portfolio‐selection techniques are used to examine the relative performance of gold bullion and SA gold shares quoted on the New York stock exchange over the period 1978 to 1983. It concludes that, on average, of the period examined gold shares have proved to be significantly better investments than gold bullion and considers possible reasons for this.
Market life, age structure and renewal—an analysis of pharmaceutical specialities and substances in Sweden 1960–82
Authors: Berlin Hans , Jönsson Bengt 
Published: June 2007

AbstractThe assortment of drugs on the Swedish market has been analysed in order to illustrate its current structure and its qualitative and quantitative changes. The analysis comprises both active substances and pharmaceutical specialities, and it has in several cases been divided into different pharmacological groups and into Swedish and imported products. The main aspects are: market life of products introduced since 1960; withdrawal of drugs; age of the current assortment of drugs; structural changes during 15 years; new drugs introduced since 1960; combinations; synonyms.
The effect of adverse publicity on sales: A case study
Authors: Happel Stephen K. 
Published: June 2007

AbstractThis paper estimates lost sales resulting from adverse publicity for a small company soon after it began selling solar hot‐water units. Ordinary least squares analysis generates estimates from seasonally adjusted data. To capture the structural shift in sales, alternative series of dummy variables are tested along with other explanatory variables. The ‘best’ of the equations is reported, and the outcome of the court suit is discussed.
The practice of decision‐making—some evidence
Authors: Hill Stephen , Blyton Paul 
Published: June 2007

AbstractThe theory of scientific decision‐making is a well developed and coherent discipline, which may be expected to have had some impact on the decision‐making processes employed by actual firms. This paper reports the results of a survey of engineering firms in South Wales, and casts some doubt on the hypothesis that advances in decision analysis have had a descernible impact on the practice of business. Moreover, the primary reason for this lack of impact appears to be that decision analysis is not perceived as relevant to the decision‐making needs of managers. The paper concludes with some suggestion for overcoming this obstacle to the application of decision analysis.
Environmental management costs using a best available control technology bact in the electrical generating industry
Authors: Willett Keith 
Published: June 2007

AbstractAs pollution control programs become an increasingly important part of government regulatory activities there also arises the question of the economic impacts of these activites. The purpose of this paper is to illustrate the use of a computable general equilibrium model for measuring the economic impacts of imposing a Best Available Control Technology (BACT) on the Electric Utilities industry. This application is intended only to demonstrate the feasibility of the approach—and is not designed for immediate policy purposes. The particular model used in this study is structured after a recently developed mathematical programming system which is designed to compute a general equilibrium solution. This system combines activity analysis with downward‐sloping demand curves, and solutions are obtained with a ‘single‐pass’ linear programming algorithm. The model's objective function plays the central role of driving the model to market‐clearing values.
Tender‐offer premia as a management signal
Authors: Polonchek John A. , Slovin Myron B. , Sushka Marie E. 
Published: June 2007

AbstractIn this paper we test whether tender‐offer premia for share repurchases can be viewed as an outgrowth of optimizing behavior by managers in a signalling environment. This is in contrast to previous work on the signalling hypothesis which focuses on the stock market's reaction to the announcement of tender offers. Our empirical results indicate that premia are systematically related to the price of the firm's stock and the level of the stock market but are not related to either management compensation, inside holdings of stock or the ratio of shares sought to total shares.
Spillovers and the cost of multiproject R&D
Authors: Van Cayseele Patrick 
Published: June 2007

AbstractThe paper presents the cost of sequential and parallel research strategies in multiproject R&D characterized by spillovers between the projects. Larger spillovers associated with a sequential strategy prove to be insufficient to guarantee a cost advantage for this option. This provides a rationale for a parallel research strategy with some duplication of effort, as observed in some real‐world R&D environments.
The design of capital budgeting processes and the corporate context
Authors: Pike Richard H. 
Published: June 2007

AbstractThis study investigates how differences in the degree of capital budgeting sophistication and formalization are related to the corporate context. A model was developed and the expectations in the model were explored with data gathered from 146 major UK firms. The results generally support the model and show that the investment procedures and techniques adopted by firms may be partly explained in terms of the corporate context.
Research and development expenditure in regulated and unregulated markets
Authors: De Villiers J. U. , Scott D. R. 
Published: June 2007

AbstractThis paper examines research and development (R and D) expenditure by firms supplying a product to both a regulated and an unregulated market. An expression for the profit‐maximizing R and D expenditure of firms operating in a dualistic market is derived from theory. This relationship is empirically tested with data from the South African pharmaceutical industry, which did not disprove the theory. The study finds the retention of the unregulated market for pharmaceuticals to be essential to provide R and D funds for the pharmaceutical industry.
Dominant stockownership and profitability
Authors: Neun Stephen P. , Santerre Rexford E. 
Published: June 2007

AbstractDominant stockholders can acquire variable amounts of control over a firm's performance. The amount of control depends largely on both the incentive and power to dominate the firm's decision‐making process. Ceteris paribus, a dominant stockholder has more incentive and power to influence firm behavior when he owns larger amounts of the firm's stock. To capture properly the effects of the separation of ownership and control this study considers a continuous relation between stockownership and control. This formulation allows for variable degrees of stockholder control, and suggests a critical minimum percentage of stockownership necessary for constraining managerial behavior.
Restrictions on outward portfolio investment and domestic equity markets
Authors: Hirst Ian 
Published: June 2007

AbstractGovernments sometimes impose restrictions on local investors which effectively prevent them from purchasing overseas equities. Reasons for doing this, from the government's point of view, would include increasing the availability of risk capital to local companies and lowering its costs. The paper analyses this argument in terms of modern portfolio theory. It is shown that, under certain circumstances, domestic equities and overseas equities may be complements rather than substitutes. In this case the effect of the restrictions would be to lower prices on the domestic stock exchange and to raise the cost of risk capital to local companies. Indications are given of the circumstances in which this effect is likely to occur. Policy makers who are not aware of the risk‐spreading motives which underly much international portfolio investment in equities are likely to overstimate the benefits to local industry from forcing local equity investors to keep their funds at home.
An optimal‐incentive contract for managers with exponential utility
Authors: Haugen Robert A. , Taylor William M. 
Published: June 2007

AbstractThis paper examines the manager–investor relationship in the case of exponential utility when the manager of investments in real or financial assets has an endowment which can be invested in the risky assets for which he has private information. We obtain a relationship showing trade‐offs or hedging behavior among the investments the manager can choose for himself and the principal. Even with the hedging ability of the manager, the well‐known first‐best solution with ‘no moral hazard’ risk‐sharing is obtained among these possible solutions to the manager's problem by specifying a ‘no conflict of interest’, zero investment by the manager of his own endowment in those risky assets for which he has private information. Thus, the agent imputes no disutility to the assignment of the principal's investments and the investor is assured of an investment strategy that he would make if he had access to the manager's private information.
Production frontier estimation to measure efficiency: A critical evaluation in light of data envelopment analysis
Authors: Sengupta Jati K. 
Published: June 2007

AbstractThe ranking and measurement of efficiency of decision‐making units by two methods—data envelopment analysis and frontier production function—may not always lead to identical results. In this framework we attempt here a critical evaluation of the frontier production function theory in terms of theoretical and empirical implications. It is shown that under certain conditions the two approaches to effciency measurement may lead to identical results.
Market size and seasonalities: The case of the UK investment trust industry
Authors: Levis Mario 
Published: June 2007

AbstractThe particular characteristics of the UK mutual funds industry provide ideal ground for examining the pertinence of the ‘Small‐size effect’ and the ‘tax‐loss‐selling’ hypothesis. The evidence indicates the presence of a modest‐size premium for smaller investment trusts, but, rather surprisingly, size in general does not appear to be a determining factor of market performance. Moreover, in spite of some variation in the rates of return around the turn of the tax year, the evidence as a whole does not unambiguously support the tax‐loss‐selling hypothesis. However, there is ground to believe that the overall poor performance of the UK investment trust industry could be due to the tax regimen governing the industry's operations during the period 1965–80.