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11.
Profitability of cow-calf production is determined largely by market prices, calf weaning weights, and cow productive life. While producers individually have no effect on prices, weaning weights and productive life have genetic influences and hence can be altered by selection programs implemented by producers. We investigate the impact of a mutation in the leptin gene (exon 2; single nucleotide polymorphism [SNP] 305) on cow-calf profitability. Prior research shows that this mutation has effects on performance and traits of fed cattle and milk production in dairy cows. Using data from a teaching-research herd, we find that it is also associated with calf weaning weights and cow productive life. A bio-economic stochastic simulation demonstrates that the mutation has statistically positive impacts on profits, suggesting that producers can profitably make use of this information.  相似文献   
12.
Using a standard 2 × 2 trade agreement model, I show that the welfare effects of a free trade agreement (FTA) depend on the asymmetry on supply and demand functions. When countries are sufficiently asymmetric with respect to the size or the demand functions, the small country tends to be better off, while the large country is worse off. Thus, the small country must compensate the large country for the FTA to be incentive‐compatible. However, in the presence of sufficient asymmetry in the supply functions, the small country is worse off, while the bigger is better off. In this case, the transfer must flow from the large to the small country. This last finding helps explain why some FTAs between rich and poor countries provide for adjustment transfers to the latter.  相似文献   
13.
14.
In the EURURALIS project, a chain of models was used to predict the changes in sustainable development indicators for European human well-being, ecology and economy issues, for four alternative scenarios of the future socio-economic development. This paper describes the biodiversity analysis of the project. Models based on general relationships between environmental factors and biodiversity loss were combined with socio-economic, land-use and environmental models to derive data that were integrated into an interactive tool for policy makers. The biodiversity analysis takes into account the effects of land-use change, climate change, fragmentation by major roads, area of unfragmented patches, nitrogen deposition, forestry and disturbance. Results show that biodiversity is projected to decrease between now and 2030 in most countries for all scenarios, indicating that it is unlikely that the EU will be able to fulfill its commitment to stop biodiversity loss by 2010. This is mainly due to urbanization and increase in stress factors, and outweighs the area increase of nature arising from land abandonment. Merits, limitations and uncertainties of this approach to biodiversity assessment are discussed.  相似文献   
15.
Food consumption causes, together with mobility, shelter and the use of electrical products, most life cycle impacts of consumption. Meat and dairy are among the highest contributors to environmental impacts from food consumption. A healthier diet might have less environmental impacts. Using the E3IOT environmentally extended input output database developed in an EU study on Environmental Impacts of Products (EIPRO), this paper estimates the difference in impacts between the European status quo and three simulated diet baskets, i.e. a pattern according to universal dietary recommendations, the same pattern with reduced meat consumption, and a ‘Mediterranean’ pattern with reduced meat consumption. Production technologies, protein and energy intake were kept constant. Though this implies just moderate dietary shifts, impact reductions of up to 8% were possible in reduced meat scenarios. The slightly changed food costs do not lead to significant first order rebound effects. Second order rebounds were estimated by applying the CAPRI partial equilibrium model. This analysis showed that European meat production sector will most likely respond by higher exports to compensate for losses on the domestic meat market. Higher impact reductions probably would need more drastic diet changes.  相似文献   
16.
An Evolutionary Approach to Financial Innovation   总被引:6,自引:0,他引:6  
The purpose of this paper is to explain why some markets for financial products take off while others vanish as soon as they have emerged. To this end, we model an infinite sequence of CAPM-economies in which financial products can be used for insurance purposes. Agents' participation in these financial products, however, is restricted. Consecutive stage economies are linked by a mapping ('transition function") which determines the next period's participation structure from the preceding period's participation. The transition function generates a dynamic process of market participation which is driven by the percentage of informed traders and the rate at which a new asset is adopted. We then analyse the evolutionary stability of stationary equilibria. In accordance with the empirical literature on financial innovation, it is obtained that the success of a financial innovation, a mutation, depends on a sufficiently high trading volume, marketing, and new and differentiated hedging opportunities. In particular, a set of complete markets forming a stationary equilibrium is robust with respect to any further financial innovation while this is not necessarily true for a set of incomplete markets.
"There is no generally accepted theory of financial innovation, but some broad generalizations of the innovation process are possible. What matters is not the invention of a financial product or process (which is often obscure) but its diffusion through the market environment".
Ted Padolski (1987) in: The New Palgrave on Money and Finance: Financial
Innovation and Money Supply (p. 68)  相似文献   
17.
We analyze the interactions between investment and local wage bargaining in a putty-clay model where the investment decision commits the firm to a particular capital intensity. This technological precommitment is used strategically in order to manipulate the bargaining outcome. We show that this strategic behavior induces a nonmonotonic relationship between the capital and labor demands of the firm and most of its environmental parameters (e.g., the bargaining power of the union, its minimum wage requirement, the capital cost). The results we obtain in our putty-clay framework thus contradict several conclusions of the standard literature on wage bargaining and investment.  相似文献   
18.
A sizeable percentage of investors are using social media to obtain information about companies (Cogent Research [2008]). As a consequence, social media content about firms may have an impact on stock prices (Hachman [2011]). Various studies utilize social media content to forecast stock market-related factors such as returns, volatility, or trading volume. The objective of this article is to investigate whether a bidirectional intraday relationship between stock returns and volatility and tweets exists. The study analyzed 150,180 minute-by-minute stock price and tweet data for the 30 stocks in the Dow Jones Industrial Average over a random 13-day interval from June 2 to June 18, 2014 using a BEKK-MVGARCH methodology. Findings indicate that 87% of stock returns are influenced by lagged innovations of the tweets data, but there is little evidence to support that the direction is reciprocal, with only 7% of tweets being influenced by lagged innovations of the stock returns. Results further show that the lagged innovations from 40 percent of stock returns affect the current conditional volatility of the tweets, while 73 percent of tweets affect the current conditional volatility of stock returns. Moreover, there is strong evidence to suggest that the volatility originating from the returns to the tweets persists for 33 percent of stocks; the volatility originating from the tweets to the returns persists for 73 percent of stocks. Last, 53 percent of stocks exhibit both immediate and persistent impacts from returns to tweets, while 90 percent of stocks exhibit both immediate and persistent impacts from tweets to returns. These results may help traders achieve superior returns by buying and selling individual stocks or options. Also, asset and mutual fund managers may benefit by developing a social media strategy.  相似文献   
19.
A premature death unexpectedly brings a life and a career to their end, leading to substantial welfare losses. We study the retirement decision in an economy with risky lifetime and compare the laissez‐faire with egalitarian social optima. We consider two social objectives: (1) the maximin on expected lifetime welfare, allowing for a compensation for unequal life expectancies, and (2) the maximin on realized lifetime welfare, allowing for a compensation for unequal lifetimes. The latter optimum involves, in general, decreasing lifetime consumption profiles as well as raising the retirement age. This result is robust to the introduction of unequal life expectancies and unequal productivities.  相似文献   
20.
The literature provides little insight as to whether a difference exists between the marketing of services and goods. Most textbooks do not address the issue of possible differences. Their neglect of the topic would seem to indicate a working hypothesis that services and goods do not differ in any meaningful way. Authors of articles and books that do address the service issue typically dwell on implied differences between goods and services. Wyckham (1975) has concluded that “in terms of marketing, services are not different from products (goods).” Wyckham’ argument and most of the other services literature, however, is non-empirical and provides little guidance as to whether a difference between goods and servicesactually exists.  相似文献   
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