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961.
The present study supplements Canadian consumer expenditure survey data with unique time use data to analyze family life cycle decisions regarding allocation of full income to market purchased consumption goods, home production, and leisure time. Results confirm that young children's presence causes families to increase their shares of full income allocated to home production and to decrease the shares of full income allocated to leisure. As a share of full income, expenditures for market goods steadily increase while expenditures for women's home production diminish as children age.  相似文献   
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While the magnitude of potential consequences might vary, most hazards encountered in pilot plant operations are the same as those experienced in full scale commercial facilities. For example, safeguarding hazardous chemicals storage and transfer, protecting reaction vessels against catastrophic failure or runaways, all require careful consideration regardless of scale. We, however, want to address some aspects of pilot plants which can introduce hazards unique or more common to their operation. To illustrate, we present some case histories from our own pilot plant experience in BASF's Chemical Engineering Department, and include a brief discussion of some corresponding safeguards to mitigate these situations.  相似文献   
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We investigate the economic feasibility of bioelectricity production from biomass in Malaysia and its impact on greenhouse gas (GHG) emissions and storage, agricultural prices, agricultural employment and deforestation. For this purpose, we develop a partial equilibrium model that projects agricultural prices, production, imports, exports, domestic consumption and land use in 5‐year increments between 2015 and 2065. Our results show that by 2030 biomass‐generated electricity can supply 36.5 per cent of the electricity generated in Malaysia, 16 times more than the 2016 electricity supply from biomass. Increased bioelectricity production from biomass will significantly reduce GHG emissions and will help Malaysia meet its commitment in the Paris Agreement to mitigate GHG emission by 45 per cent before 2030. Our modelling shows that biomass‐generated electricity creates a derived demand for waste biomass that expands the area of oil palm plantations. The expansion lowers agricultural prices, boosts agricultural employment and leads to some deforestation as landowners clear rainforest to plant oil palm trees. Nonetheless, the deforestation does not increase GHG emissions since GHG gains from bioelectricity significantly exceed GHG losses from deforestation.  相似文献   
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In this paper the impact of price risk on millet production in Niger is investigated. The hypothesis that farmers respond to output price risk is tested. The results indicate that millet acreage planted decreased when millet price risk increased or when price risk of the competing crop decreased and therefore farmers do respond to changes in risk.  相似文献   
969.
Ranking Crop Yield Models: A Comment   总被引:1,自引:0,他引:1  
This comment discusses key specification issues that may have affected the performance and, therefore, the ranking of parametric models that were compared in a recent AJAE article. A procedure to obtain the most flexible parametric model specification possible, given the particular probability distribution function on which the model is based is presented. These specifications also allow for standardized and, therefore, more valid comparisons across parametric models that are based on different probability distributions. Finally, the comment cautions against generalization of the rankings in that AJAE article and recommends that these more flexible specifications be adopted in future comparisons and applications.  相似文献   
970.
I present a consumption-based dynamic asset pricing model in which international market correlations vary counter-cyclically over time. The driving force in the model is the time-varying effective risk aversion induced by external habit formation. Market returns are driven by fundamental outputs and discount rates. When risk aversion is high, the effect of discount rates on market returns rises with the market price of risk. To the extent that countries share risk, the cross-country correlation of discount rates exceeds the cross-country correlation of fundamental outputs. In bad times, market correlations rise as returns are mostly driven by discount rates. Thus, consistent with the empirical evidence, periods of high risk aversion are associated with high market correlations and high market volatility. After calibration, my model is consistent with the observed variation in market correlations, as well as other features of asset prices including the equity premium and market volatility.  相似文献   
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