We estimate the effect of Internet on volume of trade in a major distributed marketplace. From 1997 to 2007, a period during which residential Internet use tripled, Internet increased the volume of used cars traded in California by 7.2 percent. This implies a substantial welfare gain due to reductions in market frictions of approximately $43 million per year relative to 1997 Internet penetratio...

According to literature, penetration pricing is the dominant pricing strategy for network effect markets. In this paper we show that diffusion of products in a network effect market does not only vary with the set of pricing strategies chosen by competing vendors but also strongly depends on the topological structure of the customers' network. This stresses the inappropriateness of classical "i...

Much of recent Trade theory focuses on heterogeneity of firms and the differential impact trade policy might have on firms with different levels of productivity. A common problem is that most firm level dataset do not contain information on output prices of firms which makes it difficult to distinguish between productivity differences and differences in market power between firms. This paper de...

Data on macroscopic superconducting anisotropy of MgB 2 are reviewed. The data are described within a weak coupling two-gaps anisotropic s-wave model of super-conductivity. The calculated ratio of the upper critical fields γ H = H c2,ab /H c2,c increases with decreasing temperature in agreement with available data, whereas the calculated ratio of London penetration depths γ λ = λ c /λ ab decrea...

Achieving a desirable percutaneous absorption of drug molecule is a major concern in formulating dermatological products. The use of penetration enhancers could provide a successful mean for this purpose. The aim of this study was to evaluate the effect of incorporating a few common penetration enhancers (in different concentrations) into a 0.5% w/w piroxicam (model drug) gel formulation, on th...

In this article the influence of welding parameters such as electrical current, feed rate and stick out on crack growth energy was investigated. Therefore, prepared specimens were welded in various conditions. Using the Minitab software, 18 states of 36 possible states were chosen and applied. Then a crack was crated on the weld metal and the force-displacement diagram was plotted. Comparison o...

One of the most important parameters used for determining the performance of tunnel boring machines (TBMs) is their penetration rate. The parameters affecting the penetration rate can be divided in two categories. The first category is the controllable parameters such as the TBM technical characteristics, and type and geometry of the tunnel, and the second one is the uncontrollable parameters s...