首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 295 毫秒
1.
本文运用eviews5.0,针对黑龙江省1995~2008年农业贷款和农业总产值的相关数据进行协整检验,结果表明,农业信贷投入与农业经济发展存在着长期的均衡关系。通过分析黑龙江省农业信贷投入对农业经济增长的影响,建立误差修正模型。研究农业信贷投入对黑龙江省农业总产值的贡献度,并为黑龙江省大力发展农业信贷,完善农村金融体制提出对策建议。  相似文献   

2.
本文依据2001—2009年饲料产业链上中下游产品价格的月度数据,使用Johansen模型、VEC模型等来研究猪、肉鸡和蛋鸡饲料产业链上中下游产品价格之间的长期协整关系和短期变动关系,并进行了Granger因果关系检验。研究表明,鱼粉、豆粕对于饲料价格波动的影响系数最大,但不同原料对于不同饲料的影响不一致。猪饲料是供给主导型的价格形成机制,大豆、鱼粉和玉米等都是猪肉饲料的Granger原因;肉鸡和蛋鸡饲料则是需求主导型价格形成机制,鱼粉和小麦麸是它们的Granger原因。  相似文献   

3.
本文运用eviews5.0,针对黑龙江省1995~2008年农业贷款和农业总产值的相关数据进行协整检验,结果表明,农业信贷投入与农业经济发展存在着长期的均衡关系.通过分析黑龙江省农业信贷投入对农业经济增长的影响,建立误差修正模型.研究农业信贷投入对黑龙江省农业总产值的贡献度,并为黑龙江省大力发展农业信贷,完善农村金融体制提出对策建议.  相似文献   

4.
韦震 《内陆水产》2013,(12):39-39
近期以来,国内沿海油厂在丰厚的压榨利润促使之下,继续预售豆粕远期合同,未执行合同量也继续增加。港口进口大豆的库存正在缓慢上升,然而需求也同时处于较为旺盛的阶段,现货局部紧平衡仍对价格起到支撑,油厂整体库存压力不大,而年前备货需求显现,仍继续为近期价格提供较强支撑。而后期供应面持续宽松是不争的事实,因而豆粕现货中长期依然难改下跌趋势。具体分析如下:  相似文献   

5.
在间断性状全基因组关联分析中, 当基因组数据存在复杂群体分层时, 广义线性模型需要同时考虑上百个协变量, 其求解速度会大大下降而且还会产生异常解。本研究目的是把简单回归结果中显著位点的效应值和遗传力的尺度转化为可解释的广义线性回归结果。首先对亲缘关系矩阵进行谱分解, 特征向量作为主成分(PC), 矫正间断性状中的群体分层; 再求解每一个主成分的回归系数, 并将众多协变量与其各自的回归系数相乘, 得到的乘积合并为一个新的协变量; 然后将它作为简单回归的协变量, 逐个对标记进行关联检验; 最后对筛选获得的候选数量性状核苷酸(QTN)进行广义线性模型回归分析, 将效应和方差转化为广义线性回归模型尺度。采用本研究提出的方法与直接考虑主成分的广义线性回归模型, 分别对半滑舌鳎(Cynoglossus semilaevis)的性逆转性状进行全基因组关联分析, 结果表明,本研究方法的 QTN 检测效率更高,共检测出 6 个 QTN,其中 5 个 QTN 位于 Z 染色体上, 1 个 QTN 位于 W 染色体上,并且在基因组控制方面,本研究方法的基因组控制值与直接考虑 PC 的广义线性回归模型的基因组控制值相同,均为 1.01,处于较优水平。结论认为, 基于主成分分析的简单回归尺度转换方法能够在保证准确率的情况下提升 QTN的检测效率, 实现间断性状快速稳健的全基因组关联分析, 同时检测出的 QTN能为半滑舌鳎性逆转性状的研究提供理论指导。  相似文献   

6.
为评估环境突变、被捕食、纳潮、非法捕捞和交尾死亡对资源量和渔获量的影响,及5种死亡因素和与生长有关的参数引入不确定性对估算生物学参考点(Fmax和F0.1)的影响,基于发展的可应用于研究放流增殖渔业的YPR(yield per recruitment)模型,模拟5种死亡因素不同水平下放流中国明对虾的资源变动规律。结果显示,环境突变、被捕食、纳潮、非法捕捞和交尾死亡水平越高,单位放流资源量和渔获量越少,交尾死亡尤其对累计单位放流渔获量的影响明显;在未引入不确定性时,作用于开捕前的环境突变、被捕食、纳潮和非法捕捞死亡的不同水平对生物学参考点无影响,与生长有关的参数及5种死亡因素引入不确定性可能存在低估F0.1和Fmax的现象。研究表明,减小与放流技术有关的环境突变、被捕食、纳潮和非法捕捞死亡水平对提高放流中国明对虾渔业效果有明显的作用,交尾死亡发生的时间及死亡水平对放流中国明对虾渔获有直接的影响,当参数引入不确定性时进行放流中国明对虾资源评估,生物学参考点的中位数较均值抗不确定性干扰能力更强。  相似文献   

7.
《畜禽业》2012,(7):2-3
<正>豆粕:豆粕价格6月涨势凶猛,期货由每吨3060元,已经涨到近期最高点每吨3538元,上涨458点,涨幅高达13%。现货方面,7月5日吉林大豆油厂43%蛋白豆粕价格报价3530元/t。华北地区油厂豆粕价格保持稳定,43%蛋白粕3520元/t。山东地区豆粕价格稳中略跌,报价3550元/t;江苏地区油厂价格持稳为3580元/t。但市场成交相对清淡。需求方面,进入7月份大猪集中出栏已结束,新生仔猪偏多,豆粕在仔猪的饲料中占比更高,随着后期  相似文献   

8.
时植物性饲料原料中非淀粉多糖(Non—starch polysaccharides,NSPs)的组成、分类、化学结构及在常见饲料中的分布和含量进行了分析总结。同时分析研究了NSP在动物消化道中的抗营养机理及时其他营养素的影响,提出了降低NSP抗营养作用的方法,讨论了存在的问题和时策。  相似文献   

9.
生长激素( GH)基因能够影响动物的生长,是一个与生长性状有关的基因。以315尾甘肃金鳟( Oncorhyn-chus mykiss)为研究材料,分析了GH基因外显子区域多态性,并对基因型与生长性状进行了关联性分析。 PCR-SSCP分析结果显示B等位基因在外显子2区域第903 bp处发生G/C突变,存在3种基因型AA、 AB和BB。 D等位基因在外显子5区域第3049 bp处发生T/G的突变,在3094 bp处发生C/A的突变,其中第3049 bp处发生的T/G的突变导致第157位氨基酸由组氨酸变为谷氨酰胺,为有义突变,共检测到3种基因型CC、 CD和DD个体。最小二乘法分析表明, BB基因型的全长值和体长值都显著高于AA和AB基因型( P<0.05)。 T3049 G和C3094 A突变点对全长、体长和体重均有显著性影响( P<0.05),其中CC基因型的全长值、体长值和体重值都高于DD和CD基因型。在标记辅助育种中,这些分子标记可以为甘肃金鳟遗传改良提供基础的数据和参考。  相似文献   

10.
1.春季小瓜虫病:水温12—14℃时,4—5克重的幼鳗易发生此病。这种病虽未招致直接死亡,但易引起并发症。  相似文献   

11.
This study examines the Fish Pool salmon futures contract with respect to how well the market performs in terms of the futures price being an unbiased estimator of the spot price and whether the market provides a price discovery function. Using data for 2006–2014 and with futures prices with maturities up to 6 months we find that spot and lagged futures prices are cointegrated and that the futures price provides an unbiased estimate of the spot price. We also find that, with the exception of the front month, that the causality is one-directional. The spot prices lead futures prices between 1–6 months maturity. Hence, while the spot and lagged futures prices are unbiased estimates, we do not find support for the hypothesis that futures prices provide a price discovery function. Rather, it seems that innovations in the spot price influence futures prices. This finding is not uncommon in new and immature futures contracts markets. Hence, the salmon futures market is still immature and has not yet reached the stage where futures prices are able to predict future spot prices.  相似文献   

12.
ABSTRACT

This study examines price formation of the internationally traded salmon futures exchange. Analyzing data from 2006 to 2015, the study identifies the co-integration relationship between the spot market price and 1–6-, 9- and 12-month futures contract prices. With exception of the 12-month maturity futures price, the unbiasedness hypothesis is shown to hold, thus evidence of risk neutrality and efficiency among the co-integrated pairs. Further, it is evident that the spot price provides leadership role in the price discovery function for the 1-, 2- and 6-months futures contract. On the contrary, the 3-, 4-, 5-, 9- and 12-months futures contracts provide the expected leadership role in the price discovery function, a case that supports a matured market that can be considered a necessary price risk management tool. The mixed finding is an indication of a maturing or near matured futures market. Analysis of the term structure of futures volatilities reveal that the shorter the length of the futures contract, the more volatility there is. This is because salmon prices exhibit short-term cyclical and seasonal patterns like other agricultural commodities. As such, salmon producers will be better off hedging in far month futures contracts, ceteris paribus.  相似文献   

13.
Salmon price is highly volatile and hard to predict, which obscures planning decisions and raises financing costs for market participants. This study considers hedging the spot price uncertainty with salmon futures contracts. It uses a new framework of hedging under square loss, consisting of a new objective function, an optimal hedge ratio and a measure of hedging effectiveness. The new framework aims at minimizing the expected squared forecast error. It generalizes the classical minimum variance hedging as it relaxes the assumption of known expected prices. The salmon futures contracts deliver satisfactory hedging performance, albeit constrained by low liquidity. Therefore, I suggest holding the contract through maturity rather than closing the futures and the spot positions simultaneously. This strategy alleviates the liquidity issue and saves transaction costs. All things considered, hedging with salmon futures is a moderately effective way of handling the salmon price uncertainty.  相似文献   

14.
Abstract

Granger causality tests revealed leading indicators of shrimp futures prices, implying that futures prices do not reflect all available market information and potentially fail to be an exemplary price discovery mechanism. Trading simulations confirmed that the use of some leading indicators allowed profitable arbitrage in shrimp futures trading. Shrimp futures were deficient as a hedging tool, as well. Correlations between futures and wholesale cash prices were often low, and basis risk rivaled price risk. Lack of liquidity is a likely explanation for shrimp futures’ shortcomings as a hedging tool and price discovery mechanism.  相似文献   

15.
Volatility in catfish pond bank and feed prices lead to profit uncertainty in the catfish industry. Analysis of the factors that affect those prices and development of a forecasting model would provide guidance to catfish farm managers. Error-correction models (ECM) based on cointegrating relationships among variables were specified following development of a single-equation ARIMAX model. Factors identified as those that influence catfish price were: lagged value of catfish, feed and substitute product prices, while those that influenced feed price were: lagged value of feed, corn and soybean prices. ECM estimates implied that fish price adjusts approximately 6% and feed price 22% to the long-run equilibrium in 1?month. The analysis showed that it takes less than 17?months and 5?months to correct for long-run disequilibrium for catfish and feed prices, respectively. The ARIMAX model demonstrated a better fit for both in-sample and out-of-sample forecasting for catfish price and had better out-of-sample predictive ability for feed prices.  相似文献   

16.
Salmon spot price has been highly volatile and hard to predict since mid-2000s, obscuring the industry players’ planning decisions. ARMA-GARCH and dynamic conditional correlation (DCC) models were employed on weekly data for 1995–2013 to examine the behavior of weight-class-specific prices which are directly relevant for salmon production and risk management. Two periods of different volatility regimes were identified, before and after 2006 when the salmon market was undergoing fundamental changes. Both volatility and conditional correlations increased from 1996–2005 to 2007–2013, and return dynamics became more homogenous across weight classes. This development is conducive to the functioning of the salmon futures and options exchange.  相似文献   

17.
Abstract

The objectives of this study are to analyze the interdependent behavior of lead‐lag milkfish price adjustments between vertically‐related markets (from production to consumption) as well as between five major horizontally‐related wholesale markets. Empirical results show that there is a two‐way lead‐lag cointegrating price relationship between milkfish wholesale and retail markets. Since the fish wholesale market cannot completely and quickly assimilate the retail market information, the speed of response of wholesale prices to retail price changes is relatively slow, inducing low pricing efficiency. The Taipei wholesale market appears to cause the greatest leadership impact on the milkfish price formation compared to other wholesale markets in both the long‐run and short‐run. The results also reveal that there is a high degree of integration relationship between the horizontally integrated wholesale markets (Chiayi, Changhwa and Taichung) for milkfish in the southwestern region within a short distance.  相似文献   

18.
In 2003, the United States adopted anti-dumping tariffs for Vietnamese catfish products entering the country. This study examines how these tariffs have impacted the price relationship between domestically produced and imported catfish products. Cointegration tests confirm a long-run price relationship between domestic and imported catfish, which has persisted despite the anti-dumping tariffs. However, imports are composed of catfish from Vietnam and other countries, with only the former subjected to tariffs. Results from vector error correction models suggest that Vietnamese catfish prices do not significantly influence domestic prices. Conversely, the price of catfish from countries other than Vietnam continues to impact prices received by domestic catfish farmers and processors. The domestic catfish industry is still affected by lower-priced imports from countries other than Vietnam, although some of these may be transshipments that truly originate in Vietnam. This research methodology could be adapted to investigate trade and price interactions among other aquacultured species, which will become increasingly important as global aquaculture expands.  相似文献   

19.
The producer price of catfish is becoming relatively unstable compared to the trend in previous years, necessitating the need for a complete analysis of catfish pricing and market dynamics. An understanding of the price determination mechanisms in the catfish market and the relationships between producer price, domestic processed price, and import price are important because price variability can result in significant financial losses to the domestic catfish industry. This study used a cointegration procedure to examine the long-run relationships between domestic prices of catfish and imported price. Results from unit root and cointegration tests suggest that there is a long-run equilibrium relationship between pairs of these prices. Results from Granger causality tests and error-correction model estimations suggest that the market for domestic frozen fillets plays a significant role in the price determination of imported catfish. A similar relationship is found between producer price and frozen fillet price. Some significant measures that were estimated include a frozen fillet-producer long-run price transmission elasticity of 0.162, a frozen fillet-imported fillet long-run price transmission elasticity of 3.56, and a producer-frozen fillet short-run price transmission elasticity of 0.322. High levels of fillet prices appear to have influenced the level of catfish imports. As long as distributors and restauranteurs do not see a basis for paying a premium for U.S. catfish products, they will continue to purchase the lower-priced imported catfish and consequently imports will continue to increase.  相似文献   

20.
A study was conducted to examine the long-term relationship among price of fish, harvest level, and resource condition using a bioeconomics model. Data on the annual amount of production and prices of octopus (Octopus vulgaris) in Morocco from 1970 to 2006 are plotted on a diagram to trace annual changes of price and production. The plotted pattern suggests a long-term movement of the yield-price equilibrium along the line of a theoretical long-term supply function curve of the bioeconomics model. The plotted data also suggests that there are four stages of resource exploitation for octopus in Morocco: (1) the underexploited stage from 1970 to 1987 which is characterized by small catch and low prices, (2) the maximum sustainable yield (MSY) stage from 1988 to 1998 which is characterized by moderate catch and intermediate prices, (3) the overexploited stage from 1999 to 2001 which is characterized by large catch and intermediate prices, and (4) the reduced stock stage after 2002 which is characterized by small catch and high prices. This result is consistent with the independent scientific research information on octopus harvested in Morocco. Our study indicates that an analysis of market information (i.e., amount of production and price) could be an effective tool in identifying approximate status of fishery resources.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号