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991.
We examine the return‐implied volatility relation by employing “commodity” option VIXs for the euro, gold, and oil. This relation is substantially weaker than for stock indexes. We propose several potential reasons for these unusually weak results. Also, gold possesses an unusual positive contemporaneous return coefficient, which is consistent with a demand volatility skew rather than the typical investment skew. Moreover, the euro and gold are not asymmetric. We relate the results to trading strategies, algorithmic trading, and behavioral theories. An important conclusion of the study is that important differences exist regarding implied volatility for certain types of assets that have not yet been explained in the literature; namely, the results in this study concerning commodity ETFs versus stock indexes, plus previous research on stock indexes versus individual stocks, and the pricing of stock index options versus individual stock options. © 2013 Wiley Periodicals, Inc. Jrl Fut Mark 34:261–281, 2014  相似文献   
992.
Major sports events draw unsurpassed media attention. Companies are motivated to increase their advertising investments around these events to reach large audiences in a short period. Is such an advertising surge actually beneficial though, or should companies avoid advertising in these periods because of negative effects of competitive interference? This study investigates when consumer packaged goods companies should invest in advertising to increase sales: before, during, or after the event or outside these event periods. The author estimates short- and long-term own- and cross-advertising elasticities for 206 brands using four years of weekly data. Although considerable heterogeneity exists across brands, own-advertising effectiveness diminishes especially before and during major sports events, in both the short and the long run. In addition, brands benefit less from category-demand effects through competitors' advertising. Conversely, greater increases in advertising spending resulting in significant growth in share of voice around focused, single-sport events are a successful strategy to overcome this overall general negative trend.  相似文献   
993.
The majority of researches on luxury focus on the behaviour and opinions of consumers and let drop the important role that advertising produces on them, as is done in this work and shown with a relational model. In addition to their commercial message, some remarkable and artistic advertisings convey the identitary values of luxury (IVL) characterizing luxury parent Houses. We list and analyze these IVL: craft production, raw materials, respect of craftsmen, their knowledge, know-how, gestures and traits of artistic genius. A semiotic and rhetoric analysis of two selected advertisings (Louis Vuitton, Hermès) allow to identify the semic richness of discursive content of symbolic images and identitary narratives of each luxury brand (“griffe”), revealing the implicit IVL. We conclude that strength and power of major luxury Houses lie in the global coherence they apply everywhere (creation, products, narratives and advertisings), reinforcing their brand image and attracting more loyal consumers.  相似文献   
994.
We study immigrant assimilation by analyzing whether friendship with natives is a measure of cultural assimilation, and by investigating the formation of social ties. Using the German Socio‐Economic Panel, we find that immigrants with a German friend are more similar to natives than those without German friends, along several important dimensions, including concerns about the economy, an interest in politics, and a host of policy issues. Turning to friendship acquisition, we find that becoming employed, time spent in the host country, the birth of a child, residential mobility, and additional education acquired in the host country are significant drivers of social network variation.  相似文献   
995.
996.
I propose a bribery model that examines decentralized bureaucratic decision‐making. There are multiple stable equilibria. High levels of bribery reduce an economy's productivity because corruption suppresses small business, and reduces the total graft, even though the size of an individual bribe might increase. Decentralization prevents movement towards a Pareto‐dominant equilibrium. Anticorruption efforts, even temporary ones, might be useful to improve participation, if they lower the bribe levels demanded and thus encourage small businesses to participate.  相似文献   
997.
998.
We propose methods for constructing confidence sets for the timing of a break in level and/or trend that have asymptotically correct coverage for both I(0) and I(1) processes. These are based on inverting a sequence of tests for the break location, evaluated across all possible break dates. We separately derive locally best invariant tests for the I(0) and I(1) cases; under their respective assumptions, the resulting confidence sets provide correct asymptotic coverage regardless of the magnitude of the break. We suggest use of a pre-test procedure to select between the I(0)- and I(1)-based confidence sets, and Monte Carlo evidence demonstrates that our recommended procedure achieves good finite sample properties in terms of coverage and length across both I(0) and I(1) environments. An application using US macroeconomic data is provided which further evinces the value of these procedures.  相似文献   
999.
Capital‐labour substitution and total factor productivity (TFP) estimates are essential features of many economic models. Such models typically embody a balanced growth path. This often leads researchers to estimate models imposing stringent prior choices on technical change. We demonstrate that estimation of the substitution elasticity and TFP growth can be substantially biased if technical progress is thereby mis‐specified. We obtain analytical and simulation results in the context of a model consistent with balanced and near‐balanced growth (i.e. departures from balanced growth but broadly stable factor shares). Given this evidence, a constant elasticity of substitution production function system is then estimated for the US economy. Results show that the estimated substitution elasticity tends to be significantly lower using a factor‐augmenting specification (well below one). We are also able to reject conventional neutrality forms in favour of general factor augmentation with a non‐negligible capital‐augmenting component. Our work thus provides insights into production and supply‐side estimation in balanced‐growth frameworks.  相似文献   
1000.
Helpman, Melitz and Rubinstein [Quarterly Journal of Economics (2008) Vol. 123, pp. 441–487] (HMR) present a rich theoretical model to study the determinants of bilateral trade flows across countries. The model is then empirically implemented through a two‐stage estimation procedure. We argue that this estimation procedure is only valid under the strong distributional assumptions maintained in the article. Statistical tests using the HMR sample, however, clearly reject such assumptions. Moreover, we perform numerical experiments which show that the HMR two‐stage estimator is very sensitive to departures from the assumption of homoskedasticity. These findings cast doubts on any inference drawn from the empirical implementation of the HMR model.  相似文献   
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