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141.
Despite the generally recognized importance of knowledge spillovers, the empirical literature is essentially silent on the type of innovation stimulated by spillovers. We estimate the determinants of product innovations differing in their degree of newness to the adopting firm. Knowledge spillovers from rivals have a positive impact on incremental innovations. This impact is largely independent of participation in R&D cooperation. Spillovers exert no such independent influence on drastic innovation activities. The results support the hypothesis that establishments face difficulties in using knowledge that comes from areas they are not familiar with. Establishments exploit spillovers for incremental innovations rather than for drastic innovations. To some degree R&D cooperation can help to overcome the difficulties in using spillovers for drastic innovations. Furthermore, our estimates provide evidence that the firm's own R&D effort and the use of outside information are substitutes.  相似文献   
142.
We propose a “reflexivity” index that quantifies the relative importance of short-term endogeneity for several commodity futures markets (corn, oil, soybean, sugar, and wheat) and a benchmark equity futures market (E-mini S&P 500), from mid-2000s to October 2012. Our reflexivity index is defined as the average ratio of the number of price moves that are due to endogenous interactions to the total number of all price changes, which also include exogenous events. It is obtained by calibrating the Hawkes self-excited conditional Poisson model on time series of price changes. The Hawkes model accounts simultaneously for the co-existence and interplay between the exogenous impact of news and the endogenous mechanism by which past price changes may influence future price changes. Our robustness tests show that our index provides a ‘pure’ measure of endogeneity that is independent of the rate of activity, order size, volume or volatility. We find an overall increase of the reflexivity index since the mid-2000s to October 2012, which implies that at least 60–70 percent of commodity price changes are now due to self-generated activities rather than novel information, compared to 20–30 percent earlier. While our reflexivity index is defined on short-time windows (10–30 min) and thus does not capture long-term memory, we discover striking coincidence between its dynamics and that of the price hikes and abrupt falls that developed since 2006 and culminated in early 2009.  相似文献   
143.
Under the general affine jump-diffusion framework of Duffie et al. [Econometrica, 2000, 68, 1343–1376], this paper proposes an alternative pricing methodology for European-style forward start options that does not require any parallel optimization routine to ensure square integrability. Therefore, the proposed methodology is shown to possess a better accuracy–efficiency trade-off than the usual and more general approach initiated by Hong [Forward Smile and Derivative Pricing. Working paper, UBS, 2004] that is based on the knowledge of the forward characteristic function. Explicit pricing solutions are also offered under the nested jump-diffusion setting proposed by Bakshi et al. [J. Finance, 1997, 52, 2003–2049], which accommodates stochastic volatility and stochastic interest rates, and different integration schemes are numerically tested.  相似文献   
144.
We analyze the behavior of the implied volatility smile for options close to expiry in the exponential Lévy class of asset price models with jumps. We introduce a new renormalization of the strike variable with the property that the implied volatility converges to a nonconstant limiting shape, which is a function of both the diffusion component of the process and the jump activity (Blumenthal–Getoor) index of the jump component. Our limiting implied volatility formula relates the jump activity of the underlying asset price process to the short‐end of the implied volatility surface and sheds new light on the difference between finite and infinite variation jumps from the viewpoint of option prices: in the latter, the wings of the limiting smile are determined by the jump activity indices of the positive and negative jumps, whereas in the former, the wings have a constant model‐independent slope. This result gives a theoretical justification for the preference of the infinite variation Lévy models over the finite variation ones in the calibration based on short‐maturity option prices.  相似文献   
145.
This paper analyses the extent to which the level of bank competition influences monetary policy transmission. Using a large panel dataset of 978 banks from 55 countries, and employing the Lerner index model as a measure of market structure, our results show that an increase in banking sector competition weakens the effectiveness of monetary policy on bank lending. The findings are robust to a broad array of sensitivity checks including control of alternative measurements of the Lerner index, different samples and different methodological specifications. By extension, these results have important policy implications for regulators in assessing the effectiveness of monetary policy transmission mechanisms.  相似文献   
146.
Abstract This study uses panel data on Canadian establishments to explore the relationship between the organization of work – in particular decentralization, information‐sharing, and incentive pay schemes – and innovation. Like other studies, ours finds a clear positive link between these factors. However, the data give strong indications that this relationship is not causal. We show that: (1) the correlation between workplace organization and innovation holds for information‐sharing but is much weaker for decentralized decision‐making or incentive pay programs, (2) controls for unobserved heterogeneity significantly weaken results, and (3) lagged variables give no clear evidence that organizational changes predate innovation.  相似文献   
147.
In this paper, we investigate the causal impact of workplace health and safety practices on firm performance, using Danish longitudinal matched employer–employee data merged with unique cross‐sectional representative firm survey data on work environment conditions. We estimate standard production functions, augmented with workplace environment indicators, addressing both time‐invariant and time‐varying potentially relevant unobservables in the production process. We find positive and large productivity effects of improved physical dimensions of the health and safety environment, specifically, “internal climate” and “monotonous repetitive work”.  相似文献   
148.
This note considers the competing vertical structures framework with Cournot‐Bertrand competition downstream. It shows that the equilibrium wholesale price paid by a Cournot (Bertrand)‐type retailer is above (below) marginal costs of a corresponding manufacturer. This result contrasts with the one under pure competition downstream (i.e., Cournot or Bertrand), where the wholesale price is set below (above) marginal costs in case of a Cournot (Bertrand) game at the retail level.  相似文献   
149.
The evolution of private labels (PLs) can be understood in terms of a strategy adopted by the retail industry with the aim of competing with national brands (NBs). In the 1990s, this strategy led to the development of ‘me too’ products, which currently represent the largest share of store brand products. Since the early 2000s, retailers have widened the range of their store brands by introducing high‐quality products. The aim of this study was to estimate consumers’ attachment to ‘me‐too’ and niche PLs respectively, as compared to NBs. We captured the degree of maturity of these PLs through their price‐elasticities, computed for three staple goods offered by three mass retail companies. It was found that price sensitivity does not differ much between the ‘me‐too’ PLs and the corresponding NBs. This result confirms that ‘me‐too’ products are now considered reliable quality brands. However, in the high quality segment, consumers remain more sensitive to the price of PLs than to that of NBs, a characteristic which may relate to their recent introduction on the market.  相似文献   
150.
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