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41.
We consider the problem of estimating a probability density function based on data that are corrupted by noise from a uniform distribution. The (nonparametric) maximum likelihood estimator for the corresponding distribution function is well defined. For the density function this is not the case. We study two nonparametric estimators for this density. The first is a type of kernel density estimate based on the empirical distribution function of the observable data. The second is a kernel density estimate based on the MLE of the distribution function of the unobservable (uncorrupted) data.  相似文献   
42.
The performance of service industries in Canada has been lower than that of good industries over the last four decades, with noticeable exceptions such as for railways and telecommunication carriers. Service industries were less economically (and technically) efficient in that they generated less output value (quantity) per hour worked (level and growth) or per combined unit of labour and capital (multifactor productivity growth) than good industries. The relative output price of services declined slightly over time compared with goods. At the disaggregated level, changing relative output prices were substantial and proved to be an important factor explaining the relative satisfactory economic performance of many service industries despite their low technical performance. Nevertheless, the output share of service industries increased over that period, sustained, mainly, by the growing recourse of all firms to outsourcing of services.  相似文献   
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In this paper, we argue that consideration of firm strategy can help illuminate the choices managers make between debt and equity financing. Within an industry, the form of competition that each firm chooses will determine the strategic value to the firm of maintaining financial slack. Our empirical analysis yields strong support for the proposition that financial slack should be a particularly critical strategic imperative for firms pursuing a competitive strategy premised on innovation. We also demonstrate that firms pursuing such a strategy that fail to recognize the value of financial slack are likely to perform poorly. Copyright © 2003 John Wiley & Sons, Ltd.  相似文献   
45.
The purpose of this article is to describe how households in Novgorod the Great, Russia, deal with food provision in everyday life. The study focuses on changes experienced in food provision and consumption in Russian society, in order to illustrate how households respond to the transformation towards a market economy. The study reflects women's perspective on food provision. Students from Novgorod the Great visited 105 households and asked the women in the household to answer a questionnaire. Results from the study show that in order to cope with changes in society related to economic reforms, Russian households had changed both their food consumption and food production patterns. There was no big difference between urban and rural households. Nearly all of the households were self‐sufficient in the provision of vegetables and potatoes. Many households had a ‘dacha’ (plot), where they produced most of what they needed. Among the changes experienced during recent years (i.e. during the end of the 1990s), a decade after perestroika was initiated, households mentioned the rise in food prices and the decrease of income. Households reported that they consumed less fruit and/or meat. Some households also mentioned that the quality of nourishment had decreased, thereby indicating lower general quality, lower nutrition value, or less healthy foodstuffs.  相似文献   
46.
This paper explores differences in the bidding patterns of entrants and incumbents in road construction auctions. We find that entrants bid more aggressively and win auctions with significantly lower bids than incumbents. The differences in their bidding patterns are consistent with a model of auctions in which the distribution of an entrant's costs exhibits greater dispersion than that of an incumbent's and relations of stochastic dominance in the distributions do not persist for the entire range of estimated costs. We also find that more efficient firms bid, on average, more aggressively and firms with greater backlogs bid less aggressively.  相似文献   
47.
In rational, efficiently functioning and complete markets, returns on derivative and underlying securities should be perfectly contemporaneously correlated. Due to market imperfections, one of these markets may reflect information faster. The use of high-frequency data and the choice for a small unit time interval to measure these lead-lag relations comes at the cost of some or many missing observations, causing traditional estimators to either under- or overestimate covariances and correlations. We use a new estimator to estimate lead-lag relationships between the cash AEX index, options and futures. We find that futures returns lead both options and cash index returns by approximately 10 minutes. The relationship between options and the cash market is not completely unidirectional.  相似文献   
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Abstract The research question in the present article can be phrased in the following way: what are the elements which influence the perception of the utility of information received from another function? A field study research has been conducted in 40 Belgian companies. In each company, we have studied two on-going innovation projects (one planning project, one development project). Crossfunctional communication behaviours at the R&D/marketing interface have been measured by means of mailed structured questionnaires. Three-hundred and eighty-six questionnaires have been returned. The data analyses show that there are four underlying information dimensions, i.e. the perceived relevance, the perceived comprehensibility, the perceived novelty and the perceived credibility of information. We also discuss some contingency variables (function of the message receiver, stage in the innovation process) that might moderate the impact of these dimensions. It will be shown that the interaction between source and receiver has a significant impact on the perceived credibility, the perceived comprehensibility and the perceived novelty of the received information.  相似文献   
50.
The introduction of traffic management schemes has been one response of the National Parks to the problem of ever-increasing car-borne visitors and the consequent damage caused to the rural environment. By reviewing these schemes and by determining and explaining attitudes towards one particular traffic management experiment, the paper aims to deduce lessons for future policy. The analysis, based on two visitor surveys, suggests that the likelihood of success is improved when schemes are integrated, containing both ‘carrot’ and ‘stick’ elements. Since public perceptions are also found to be pivotal to its success, appropriate marketing of a scheme is vital. The paper concludes, however, that to achieve the fundamental objective of greater accessibility with less mobility, a more wide-ranging marketing effort is required intended to engender a sea change in attitude towards both the car and public transport.  相似文献   
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