bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Set of Better Quasi Orderings is ∏
Authors: Marcone Alberto 
Published: June 2007

AbstractIn this paper we give a proof of the II12‐completeness of the set of countable better quasi orderings (viewed as a subset of the Cantor space). This result was conjectured by Clote in [2] and proved by the author in his Ph.d. thesis [6] (see also [7]). Here we prove it using Simpson's definition of better quasi ordering ([15]) and as little bqo theory as possible.
Some New Lattice Constructions in High R. E. Degrees
Authors: Rolletschek Heinrich 
Published: June 2007

AbstractA well‐known theorem by Martin asserts that the degrees of maximal sets are precisely the high recursively enumerable (r. e.) degrees, and the same is true with ‘maximal’ replaced by ‘dense simple’, ‘r‐maximal’, ‘strongly hypersimple’ or ‘finitely strongly hypersimple’. Many other constructions can also be carried out in any given high r. e. degree, for instance r‐maximal or hyperhypersimple sets without maximal supersets (Lerman, Lachlan). In this paper questions of this type are considered systematically. Ultimately it is shown that every conjunction of simplicity‐ and non‐extensibility properties can be accomplished, unless it is ruled out by well‐known, elementary results. Moreover, each construction can be carried out in any given high r. e. degree, as might be expected. For instance, every high r. e. degree contains a dense simple, strongly hypersimple set A which is contained neither in a hyperhypersimple nor in an r‐maximal set. The paper also contains some auxiliary results, for instance: every r. e. set B can be transformed into an r. e. set A such that (i) A has no dense simple superset, (ii) the transformation preserves simplicity‐ or non‐extensibility properties as far as this is consistent with (i), and (iii) A T B if B is high, and A ≥T B otherwise. Several proofs involve refinements of known constructions; relationships to earlier results are discussed in detail.
Constants in Kripke Models for Intuitionistic Logic
Authors: Dzierzgowski Daniel 
Published: June 2007

AbstractWe present a technique to extend a Kripke structure (for intuitionistic logic) into an elementary extension satisfying some property (cardinality, saturation, etc.) which can be “axiomatized” by a family of sets of sentences, where, most often, many constant symbols occur. To that end, we prove extended theorems of completeness and compactness. Also, a section of the paper is devoted to the back‐and‐forth construction of isomorphisms between Kripke structures.
Non‐associative Lambek Categorial Grammar in Polynomial Time
Authors: Aarts Erik , Trautwein Kees 
Published: June 2007

AbstractWe present a new axiomatization of the non‐associative Lambek calculus. We prove that it takes polynomial time to reduce any non‐associative Lambek categorial grammar to an equivalent context‐free grammar. Since it is possible to recognize a sentence generated by a context‐free grammar in polynomial time, this proves that a sentence generated by any non‐associative Lambek categorial grammar can be recognized in polynomial time.
A General Type for Storage Operators
Authors: Nour Karim 
Published: June 2007

AbstractIn 1990, J. L. Krivine introduced the notion of storage operator to simulate, in λ‐calculus, the “call by value” in a context of a “call by name”. J. L. Krivine has showed that, using Gödel translation from classical to intuitionistic logic, we can find a simple type for storage operators in AF2 type system. In the present paper we give a general type for storage operators in a slight extension of AF2. At the end we give (without proof) a generalization of this result to other types.
Intuitionistic ϵ‐ and τ‐calculi
Authors: Devidi David 
Published: June 2007

AbstractThere are several open problems in the study of the calculi which result from adding either of Hilbert's ϵ‐ or τ‐operators to the first order intuitionistic predicate calculus. This paper provides answers to several of them. In particular, the first complete and sound semantics for these calculi are presented, in both a “quasi‐extensional” version which uses choice functions in a straightforward way to interpret the ϵ‐ or τ‐terms, and in a form which does not require extensionality assumptions. Unlike the classical case, the addition of either operator to intuitionistic logic is non‐conservative. Several interesting consequences of the addition of each operator are proved. Finally, the independence of several other schemes in either calculus are also proved, making use of the semantics supplied earlier in the paper.
Microeconomic foundations of corporate strategy
Authors: Naylor Thomas H. , Thomas Celia 
Published: June 2007

AbstractThis paper examines several approaches to corporate strategic planning in the context of their relationship to the microeconomic theory of the firm, and discusses the implications of that theory for corporate strategy in general. Specifically, three types of analytical tools are discussed: (1) analytical portfolio models; (2) business simulation models; and (3) optimization models. Examples of how the three types of tools are used in corporate decision‐making are given, and certain limitations are cited. The limitations include, for example, the inability of some of the models to deal with interdependencies across business units in production resources or output demand. Finally, the paper examines the approach to strategic planning known as the ‘strategy matrix’, which explicitly allows for interdependices across business units. The use of the strategy matrix by a major petroleum company is discussed in some detail.
Industrial organization and the evolution of concepts for strategic planning: The new learning
Authors: Porter Michael E. 
Published: June 2007

AbstractThis paper reviews the parallel development of the disciplines of corporate strategy and industrial organisation. Recent developments in industrial economics suggest that the two may be about to merge, or at least be capable of synergy. This potential advance has come about because of the movement of industrial organisation theories towards dynamics and away from static concepts such as the traditional structure: conduct: performance model. Simultaneously, corporate strategists, who have always been dynamically oriented, have long been in search of the more sophisticated theories industrial economists have in their tool kits.
Foreign location decisions by US transnational firms: An empirical study
Authors: Hollander Abraham 
Published: June 2007

AbstractThe paper aims at identifying the variables that are significant in determining the choice of host countries for manufacturing subsidiaries of US transnational firms. The approach that is taken is to relate variables that on the basis on a priori theoretical reasoning influence foreign location decisions, with (a) total market penetration by US firms and (b) the choice these firms make between exporting to their foreign markets and on site manufacturing. Location decisions are viewed as emerging from the interaction of characteristics typical to the industry of the transnational firm and factors specific to potential host countries. Particular attention is devoted to finding out whether locational choices and market shares are interdependent. The sample of observations under investigation consists of the activities of US majority‐owned subsidiaries, classified in fourteen industry groupings and operating twenty countries. Sub‐samples of countries are also studied. It is found that for the European countries, in particular EEC members, market penetration is dependent on local manufacturing.
Some refinements in austrian trade‐cycle theory
Authors: Wood J. Stuart 
Published: June 2007

AbstractChanges in the apparent rate of interest have different effects upon different types of firms, causing the onset of the business cycle to be initiated in specialty suppliers to high‐order capital goods manufacturers. These specialty manufacturers utilize bank loans to finance inventories, so they are sensitive to changes in market rates, while consumer‐goods manufacturers finance capital projects using long‐term sources of funds, which are less sensitive. The abandonment of capital projects by lower‐order manufacturers is also less sensitive to interest rate movements than the manufacturing operations of the high‐order suppliers.
Technological change in health care: Why are opinions so divided?
Authors: Zweifel Peter 
Published: June 2007

AbstractThis paper purports to explain the widespread scepticism towards technological change in health care in general and pharmaceutical innovation in particular in the face of very high estimated rates of social return. These estimates are based on observable market prices and quantities, which are used for measuring the additional consumer surplus induced by an innovation. They grossly overstate true surplus due to the effect of insurance, however. For true demand for health care services and hence true surplus depends on the net price a patient is willing to pay, which is a rather small fraction of observed market price. The paper also outlines the conditions under which a health insurer would welcome a pharmaceutical innovation.
Concentration change and the structure—performance debate: An interpretive essay
Authors: Carter John R. 
Published: June 2007

AbstractIt is demonstrated that the hypotheses and tests found in the concentration change literature fail to discriminate adequately among the competing theories. This failure is characteristic of the larger structure‐performance debate, raising the question of whether there is something in the nature of the debate which permits it to persist but never really progress. It is argued that the debate is derived in large part from differences which on one level are purely semantic but which on a deeper level concern the normative bases up on which market outcomes are interpreted. If a meaningful resolution is to be hoped for, it must be sought at much deeper levels of inquiry.
A study of measuring influence of advertising and forecasting cigarette sales
Authors: Yucelt Ugur , Kaynak Erdener 
Published: June 2007

AbstractThis study investigated the effect of advertising on cigarette sales, particularly after 1967. Data were collected using sources of the Statistical abstract of the U.S., the Historical Statistics of the U.S. and Vital Statistics between 1955 and 1979. A multiple regression model was used to analyze the data. Cigarette consumption was used as a dependent variable. Disposable Income, Death Rate due to cancer of the respiratory system/total cancer death, advertising outlays for cigarettes: Newspapers and television advertisement/total advertising cost, cigarette‐production (including long and regular sizes), sales outlets, loyalty/total loyalty, average price for cigarettes and a dummy variable were used as independent variables. Analysis revealed that there is a significant negative relationship between cigarette‐consumption and total cancer death and average prices on the one hand, and a significant positive association between loyalty and cigarette consumption on the other. Although advertising expenditures are not statistically significant, increased spending on advertising has an increasing effect on cigarette‐consumption.
Advertising expenditure and aggregate consumption in Britain and West Germany: An analysis of causality
Authors: Sturgess Brian T. , Wilson Nicholas 
Published: June 2007

AbstractThis paper surveys past work which attempts to investigate the effects of advertising on the macro‐economy, in particular on the allocation of income to consumption expenditure. It is argued that many prior studies aimed at testing this ‘Galbraithian’ hypothesis have suffered from an inability to detect the direction of any causal flows and may have only detected spurious relationships. Here, the relationship is analysed for West Germany and Great Britain, with the use of bivariate time series modelling techniques considered initially by Granger and Newbold. The advantages and disadvantages of using the concept of ‘Granger Causation’ are considered in relation to testing this area of interest. No support is found for the proposition that advertising has a positive causal effect on aggregate consumption in the two countries.
Organizational capital and the choice between specialization and diversification
Authors: Gort Michael , Grabowski Henry , McGuckin Robert 
Published: June 2007

AbstractThis paper specifies a model in which the preservation of organizational capital is the principal factor motivating corporate diversification decisions. Alternative hypotheses of the determinants of diversification are then subjected to empirical test with data for 96 US industrial firms in the 1967–71 period. Consistent with the model, variables associated with unfavorable expectations on the marginal returns to investment in existing activities proved dominant in explaining ‘desired’ increases in diversification. Alternative explanations, namely, the role of managerial attributes, of absolute advantages of some firms, and of opportunities created by research and development, had more modest explanatory power.
Learning by a dominant firm
Authors: Harpaz Giora 
Published: June 2007

AbstractThis paper is concerned with the optimal output decisions of a dominant firm in the presence of imperfect information about the rival's reactions. The model is multi‐period with the profits in each period being independent of those in other periods. Consequently, if the rival's reaction parameter were known to the dominant firm, a myopic policy would be optimal, In the presence of imperfect information about the rival's unknown reaction parameter, the dominant firm acts in a Bayesian manner by updating its prior distribution based on the observations of the rival's outputs. Because of the multiplicative shape of the rival's reaction function, the Bayesian updating rule is a function of the dominant firm's decision variable, i.e. its output decisions. This creates a dependence of the future value of the dominant firm on the present output decision, and hence a myopic policy is not, in general, optimal. It is shown that through output experimentation the dominant firm will tend to overproduce and, consequently, will increase its expected discounted profits (market value).
Security‐holder cash flows and the valuation of corporate investment projects
Authors: Lewellen Wilbur G. , Emery Douglas R. 
Published: June 2007

AbstractThe difference between adjusted present value and cost‐of‐capital discounting procedures for evaluating corporate real‐asset investment projects is re‐examined. The two approaches are shown to contain different implicit assumptions about the distribution of project cash flows to security‐holders. The consequences thereof for the proper valuation of individual projects in the context of a multiproject investment plan are considered.
The organization and relative productivity of Japanese and American industry
Authors: Comanor William S. , Miyao Takahiro 
Published: June 2007

AbstractThis paper compares the structure and productivity of Japanese and American firms. We construct a simple model of labor shares in which the ratio of labor payments to sales is the product of labor's share in take added and the degree of integration. According to Japanese and United States census data, labor shares in value added are fairly similar for Japanese and American firms, whereas the average degree of integration, and therefore the average ratio of payroll to sales of Japanese firms, is distinctly lower than that of their American counterparts, particularly in the machinery and equipment industries.From survey data on Japanese firms in California, we observed payroll‐sales ratios that generally lie between values reported for Japan and the United Slates for the machinery and equipment industries. Assuming that Japanese firms in California employ the same technology as their US counterparts, we conclude that the average degree of integration of Japanese firms in California is at least 10% lower. As a result, even though the gross labor productivity of typical Japanese firms in the United States generally, and California in particular, is slightly higher, the former may well be less productive than the latter in terms of net lalmr productivity, measured by value added.While further corroboration is needed, it appears that differences in the extent of integration are an important factor that accounts for reported productivity difference between the two countries.
Generic substitution in the UK pharmaceutical industry: A markovian analysis
Authors: Reekie W. Duncan , Allen D. E. 
Published: June 2007

AbstractThis paper examines the impact of competition on product market shares in the UK pharmaceutical industry. The topic is of particular interest since, although it is well known that such products are already subject to competition by innovation and by price (Cooper, 1966, Ch. 3; Reekie, 1978), the possible introduction in the UK of generic substitution (Greenfield, 1982, p. 24), could further increase competitive pressures. Our aim is to apply Markov probabilistic analysis to existing market data. This will enable us (after Adelman, 1958) to analyse the structure which the industry will ‘eventually reach if certain current trends were to continue’ (Adelman, p. 893). In particular, we apply the technique to sub‐samples of the data, to infer how the competitive process influences the industry's configuration when generic competition is present. The outcome can be used as a conservative indicator of the impact on the industry if generic substitution was to be adopted in the National Health Service (NHS).The plan of the paper is as follows. In the first section a brief resumt of the debate which has surrounded generic substitution proposals is presented. The second section details the data and sample used in our empirical work. The third section applies Markov chain analysis to that data and reports our results. The final section summarizes our conclusions and discusses some of the problems and limitations of our results.
On the probability of entry in potential competition cases
Authors: Horowftz Ira 
Published: June 2007

AbstractThis paper explores, both theoretically and empirically, the extent to which having ‘other potential entrants’ to a market injected into potential‐competition cases has been a worthwhile enterprise. This two‐pronged attack leads to the conclusion that (he attempt to specifically identify potential entrants probably results in our deluding ourselves as to the likelihood that entry will occur, and that unless a convincing argument can be made to the effect that any given potential entrant from a stockpile of unnamed potential entrants is ‘reasonably likely’ to elect the entry option, expanding lhat stockpile will be similarly misleading.
Lysosomal hydrolases in cerebrospinal fluid from subjects with Parkinson's disease
Authors: Balducci Chiara , Pierguidi Laura , Persichetti Emanuele , Parnetti Lucilla , Sbaragli Michele , Tassi Carmelo , Orlacchio Aldo , Calabresi Paolo , Beccari Tommaso , Rossi Aroldo 
Published: June 2007

AbstractRecent studies have shown a genetic association between glucocerebrosidase deficiencies and Parkinson's disease (PD). To further explore this issue the activity of β‐glucocerebrosidase and the activities of other lysosomal enzymes, α‐mannosidase, β‐mannosidase, β‐hexosaminidase, and β‐galactosidase have been evaluated in the cerebrospinal fluid (CSF) of PD patients. The activities of α‐mannosidase, β‐mannosidase, β‐glucocerebrosidase, and β‐hexosaminidase were substantially decreased in the CSF of PD patients, while levels of β‐galactosidase were essentially identical to controls. This study indicates that in PD several lysosomal hydrolases have decreased activities, further supporting a possible link between pathophysiological mechanisms underlying PD and lysosomal hydrolases. © 2007 Movement Disorder Society
Patient‐reported outcome II: selecting appropriate measures for musculoskeletal care
Authors: Haywood Kirstie L 
Published: June 2007

AbstractThe first article in this series outlined the important contribution that well developed patient reported outcome measures (PROMs) can make to healthcare, clinical decision making and evaluation. The increasing focus on patient reported health means that there are now hundreds of questionnaires available; selecting the appropriate measure is both challenging and essential. This article will introduce potential users of PROMs to key information to consider when selecting and using PROMs in research, routine practice or quality assurance. Important concepts, such as measurement reliability, validity and responsiveness to important change in health, will be explored and illustrated with examples from musculoskeletal healthcare. Practical properties, such as acceptability and feasibility, will also be introduced. Copyright © 2007 John Wiley & Sons, Ltd.
Characterization of brain metastases using high‐resolution magic angle spinning MRS
Authors: E. Sjøbakk Torill , Johansen Roar , Bathen Tone F. , Sonnewald Ursula , Juul Roar , Torp Sverre H. , Lundgren Steinar , Gribbestad Ingrid S. 
Published: June 2007

AbstractThe objectives of this study were to (a) explore the spectral characteristics of brain metastases, focusing on the origin of the primary cancer, and (b) evaluate the correlation with clinical outcome using multivariate analysis. High‐resolution magic angle spinning (HR‐MAS) MR spectra (n = 26) were obtained from 16 patients with brain metastases using a Bruker Avance DRX600 instrument. Standard pulse‐acquired and spin‐echo (TE 32 and 285 ms) 1H spectra were obtained. These were examined using principal component analysis (PCA) and partial least squares regression analysis (PLS) relating spectral data to clinical outcome. The PCA score plot of pulse‐acquired HR‐MAS spectra showed a trend of clustering due to the origin of the metastases, mainly based on differences in the lipid signals at 1.3 and 0.9 ppm. With PLS, spectra of patients who died less than 5 months after surgery appeared to cluster in the lower left quadrant of the score plot. These preliminary results on brain metastasis classification and prediction of survival must be validated in a larger patient cohort. However, the possibility of differentiating metastases according to origin and predicting survival on the basis of HR‐MAS spectra suggests that this method may be useful for diagnosing and planning treatment for brain metastases and also for guiding decisions about terminating further treatment. Copyright © 2007 John Wiley & Sons, Ltd.