OBJECTIVE To evaluate the use of e-procurement to obtain supplies for a network of seven university hospitals with a joint purchase system. METHODS The study was carried out between October 2003 and October 2005. We analyzed nine joint purchases of 37 pharmaceutical items. All the items were purchased in at least two-thirds of the nine occasions and/or were among the 10 items with the highest...

Prior research has shown that information security breaches are beneficial to the stock price of information security firms, around the time that these security breaches are announced. We, however, show that the overall trend in the market value of information security firms has actually been stagnating, despite an increasing number of security threats that exploit vulnerabilities in informatio...

the main purpose of this study is to determine welfare impacts of trade liberalization on maize market. for this purpose, we used from time series data for the period 1961/2009 and estimated domestic supply, domestic demand and import demand for maize. results of estimation showed that price elasticity of supply and demand is 0.32 and -0.25, respectively. then, by means of these elasticities, w...

T seller’s threshold price in name-your-own-price auctions varies over time. However, consumers must bid without knowing when these variations occur because the threshold price is unobservable to them. This paper uses an analytical model and laboratory auctions to explore how the frequency of changes in the threshold price impacts consumer bidding behavior in name-your-own-price auctions. In pa...

This paper examines the competitiveness of winner-take-all price competition in homogeneous product oligopoly environments where underlying buyer demands and/or firms’ costs need not be continuous. Our analysis is motivated by the observation that a variety of economic settings have these features. For example, in 1996 an Ivy League university solicited bids from several vendors for its initiat...

Recent literature on realized volatility suggests that the observed price process of an asset may be decomposed into two parts: the unobservable, efficient price process and microstructure noise. In this article we present a methodology to sequentially estimate spot volatility from noisy data by separating these components. We use different liquidity-based measures, traded volume and quoted spr...

We consider a continuous-time model of financial market with proportional transaction costs. Our result is a dual description of the set of initial endowments of self-financing portfolios super-replicating Americantype contingent claim. The latter is a right-continuous adapted vector process describing the number of assets to be delivered at the exercise date. We introduce a specific class of p...

True spreads are not directly observable and represent the continuous demand and supply schedule for stock liquidity by heterogeneously informed market participants. Observed spreads are true spreads quantized by minimum market tick size. A regression model of true spreads is developed using spread data from a pure limit order electronic exchange. True spreads are modelled as a continuous posit...

In the last years, increasing attention is being spent towards the applications of solar energy to electric and also to hybrid cars. But, while cars only fed by sun do not represent a practical alternative to cars for normal use, the concept of a hybrid electric car assisted by solar panels appears more realistic (Letendre et al., 2003; Fisher, 2009). The reasons for studying and developing a H...