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951.
This paper conducts a cross-country empirical study of the impact of institutions and agency conflicts on ownership reforms and their implications for changes in performance and efficiency. We examine two main questions. First, we evaluate the effects of certain property rights and institutional quality measures on performance and efficiency. We find that property rights and contracting rights protections contribute to stronger post-privatization performance. Second, we ask whether sectors undergoing changes from state to private ownership exhibit better or worse performance than sectors remaining public. We find an insignificant effect of privatization in ordinary least squares estimates and a negative short-term effect after correcting for endogeneity of privatization decisions that disappears in the long run, consistent with recently privatized enterprises facing short-run costs of restructuring and the challenges of mitigating agency and expropriation concerns.  相似文献   
952.
This paper presents new evidence on the relationship between competition and innovation by extending previous literature from manufacturing to financial services. We introduce a new measure of overall innovation by estimating and enveloping annual minimum cost frontiers to create a global frontier. The distance to the global frontier constitutes each bank’s technology gap, which decreases if the bank manages to innovate. Our innovation measure enables us to derive and estimate the model of Aghion et al. (2005b) at the firm level for the US banking industry. Based on individual bank Call Report data for the period 1984–2004, consistent with theoretical and empirical work by Aghion et al., we find evidence of an inverted-U relationship between competition and innovation that is robust over several different specifications. Further evidence on major structural changes in the US banking industry indicates that banks moved beyond their optimal innovation level and that interstate banking deregulation resulted in lower bank innovation. Policy implications to financial reform and prudential regulation are discussed also.  相似文献   
953.
The objective of this paper is to examine the impact of product market competition on earnings quality. Based on a sample from the US manufacturing sector for the period 1996–2005, we find consistent evidence showing a positive relation between product market competition and earnings quality. Additional tests also confirm a positive relation between product market competition and the precision of public and private information held by investors and analysts. We also provide evidence that firms competing in concentrated and heterogeneous industries are associated with a number of earnings attributes and information quality not shared by those competing in concentrated but homogeneous industries. These findings are consistent with the intuition that firms enjoying a monopolistic advantage tend to avoid the attention of their competitors and politicians by creating a more opaque information environment.  相似文献   
954.
2013年,法国新政府在教育和科研领域将逐步推进各项改革,其教研部拟推进的主要措施有:取消“盖昂通函”,推行决策会商工作机制,实施超级联合大学计划,颁布新高等教育和科研法,确定未来科研优先领域,强化对欧盟科研影响力和加强科研人才队伍建设等。法国政府希望通过采取以上措施,继续保持法国的世界科技强国地位和优势。  相似文献   
955.
Patterned innovation dynamics - investment-mix shifts and inter-organizational alliances -are examined for their roles in facilitating accelelating technical advance in the telecom industry since the mid-1970s. While internal investment shifts favoring R&D and declining rates of capital recovery were ubiquitous across the period, this was especially so for telecom equipment suppliers. Comparative analyses suggest that such innovation investment strategies have been of less benefit to telecom firms than to producers in nearly any other major manufacturing sector. Trends in organizational innovation in the form of alliance fonnation are also reported. The challenges these innovation dynamics pose for neoclassical models are discussed.  相似文献   
956.
The aim of the article is to relate the formation of influence networks to the coexistence of technologies in the long run. In the spirit of Plouraboue et al. (1998), we postulate that potential adopters of a technology are situated in a social network. In our model, initial relations are partly negative and all the expected utilities are revised in parallel. In the case of an exogenous network, opinions can fluctuate endlessly. When agents reallocate their relationships, this reinforces trust in agents whose opinion is close to theirs. As a result of this process, the network stabilizes in the long run, generating diversity in expected utilities.  相似文献   
957.
The purpose of this paper is to describe the impact of investment in computers on the growth of the U.S. economy. The economic literature on computers is relatively rich in information on the decline in computer prices and the growth of computer investment. Constant quality price indices for computers have been included in the U.S. National Income and Product Accounts (NIPA) since 1986. These indices employ state of the art methodology to capture the rapid evolution of computer technology.

While the annual inflation rate for overall investment has been 3.66 percent for the period 1958 to 1992, computer prices have declined by 19.13 percent per year! Similarly, overall investment grew at 3.82 percent, while investment in computers increased at an astounding 44.34 percent! These familiar facts describe growth in the output of computers. The objective of this paper is to complete the picture by analyzing the growth of computer services as inputs.

In a pioneering paper Bresnahan (1986) has focused on pecuniary externalities arising from the rapid decline in computer prices. Griliches (1992, 1994) has emphasized the distinction between pecuniary and nonpecuniary externalities in the impact of computer investment on growth. This paper is limited to pecuniary externalities or the impact of reductions in computer prices on the substitution of computer services for other inputs. As Griliches (1992) points out, this is an essential first step in identifying nonpecuniary externalities or ‘spill-overs’ through the impact of a decline in computer prices on productivity growth. * *Brynjolfsson (1993) has proveded a detailed survey of studies of nonpecuniary externalities or ‘spill overs’. Recent studies include those of Brynjolfsson and Hitt (1994a, 1994b) and Lichtenberg (1993).

In two important papers Stephen D. Oliner (1993, 1994) has introduced a model of computer technology that greatly facilitates the measurement of computer services as inputs. In this paper we estimate computer stocks and flows of computer services for all forms of computer investment included in NIPA. We construct estimates of computer services parallel to NIPA data on computer investment by combining these data with information on computer inventories. For example, the International Data Corporation (IDC) Census of Computer Processors includes an annual inventory of processors in the U.S.

In Section 1 we present data on investment in computers and constant quality price indices from NIPA. These data incorporate important innovations in modeling computer technology stemming from a joint study by IBM and the Bureau of Economic Analysis (BEA) completed in 1985. This study utilized a ‘hedonic’ methodology for constructing an econometric model of computer prices that accurately reflects rapid changes in computer technology. This methodology generates an index of computer prices that holds the quality of computers constant.

In Section 2 we present the model of computer services originated by Oliner (1993,1994). This differs in important respects from the model of capital services used in the previous studies of U.S. economic growth surveyed by Jorgenson (1989,1990). The model employed in previous studies is based on the decline in productive capacity with the chronological age of a capital good. Oliner assumes that computers maintain their productive capacity until they are retired. Decline in productive capacity occurs only through removal of used computers from the inventory through retirement.

In Section 3 we construct estimates of stocks of computers that incorporate IDC data on computer inventories and derive the implied flow of computer services. While output of computer investments has grown very rapidly, the input of computer services has grown even faster. The price of these services has declined at 23.22 percent per year over the period 1958 to 1992, while the input of these services has grown at 52.82 percent! This is prima facie evidence of an important role for computer price declines as a source of pecuniary externalities.

In Section 4 we combine computer services with the services of other types of capital to produce a measure of capital input into the U.S. economy. We link this with labor input to obtain the contributions of both inputs to U.S. economic growth, arriving at the growth of productivity as a residual. We find that the contribution of computer services to input into the U.S. economy is far more important than the contribution of computer investments to output. This is a significant step toward resolution of the Solow paradox: ‘We see computers everywhere except in the productivity statistics. * *Robert M. Solow, quoted by Brynjolfsson (1993). Declines in computer prices generate very sizable pecuniary externalities through the substitution of computer services for other inputs. By contrast Solow focuses on nonpecuniary externalities that would appear as productivity growth.

In Section 5 we conclude that information on inventories of computers is critical in quantifying the role of computer services as inputs. The constant quality price indices for computers incorporated into NIPA are also essential. A price index for computers that reflects only general trends in inflation would result in a highly distorted perspective on the growth of GDP and capital services, especially during the past decade. To capture the contribution of all forms of investment to U.S. economic growth, similar price indices should be included in NIPA for capital goods with rapidly evolving technologies, as proposed by Gordon (1990).

The long term goal should be a unified system of income. product, and wealth accounts, like that proposed by Laurits Christensen and Jorgenson (1973) and Jorgenson (1980). This incorporates capital stocks, capital services, and their prices. Achieving this goal will necessitate much greater elaboration of the accounting system described in Section 3. These accounts would incorporate data on prices and quantities of investment, stocks of assets, and capital services for all forms of capital employed in the U.S. economy.  相似文献   
958.
Empirical analyses of research and development find strong evidence that these activities tend to cluster geographically. Clusters are thought to emerge from the presence of localized positive externalities. This paper presents a model of this clustering behaviour. We find that phase changes in clustering exist both as the strength of local externalities changes and as the degree of heterogeneity among firms changes. The dynamics of the system are examined as it responds to shocks to the size of the market for R&D output, and the length scale of the spatially dependent externalities. Dynamic responses take place in two distinct stages: a rapid response to the change in market systems which takes place throughout the space, with litlle regard to externality effects; followed by a slow re-agglomeration process as producers change their spatial decisions to lower the costs of the new production level.  相似文献   
959.
Significant changes have taken place in the world wheat market in the last decade. Russia, a former net wheat importer, has become a leading exporter with a world market share of 11.2% in 2009. This increasing importance and the discussion about the establishment of a grain‐OPEC consisting of Ukraine, Kazakhstan and Russia has raised the issue of pricing behaviour of Russian wheat exporters. Although there are several studies on the pricing behaviour of Canadian and US wheat exporters, there is none so far for Russian wheat exporters. This study provides a quantitative analysis of the pricing behaviour of Russian wheat exporters, explicitly taking account of the export tax imposed between 2007 and 2008. We employ a pricing‐to‐market (PTM) model on quarterly Russian wheat‐export data, covering the period from 2002 to 2010 and 25 export destinations. Our findings indicate that (i) Russian wheat exporters exercised PTM in only a few importing countries over the whole time period, and (ii) PTM behaviour was more pronounced in the aftermath of the export tax period (i.e. 2008–2010) than before.  相似文献   
960.
This paper demonstrates how the risk over auction revenue at fundraising events can be managed with modern portfolio theory. Within the independent private values (IPV) framework, it is shown that auction mechanisms offer charities an inherent mean-variance tradeoff over revenue when contributions produce a public good benefit among bidders. This allows the fundraiser to construct a “portfolio” of auction mechanisms for their event so as to manage auction revenue outcomes according to the charity's risk preferences. Simulations provide support for the empirical prominence of the second-price winner-pay (i.e. English) auction, as this is often the portfolio's most heavily weighted mechanism under reasonable risk preferences.  相似文献   
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