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Structured Multi-Head Attention Stock Index Prediction Method Based Adaptive Public Opinion Sentiment Vector
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作者 Cheng Zhao Zhe Peng +2 位作者 Xuefeng Lan Yuefeng Cen Zuxin Wang 《Computers, Materials & Continua》 SCIE EI 2024年第1期1503-1523,共21页
The present study examines the impact of short-term public opinion sentiment on the secondary market,with a focus on the potential for such sentiment to cause dramatic stock price fluctuations and increase investment ... The present study examines the impact of short-term public opinion sentiment on the secondary market,with a focus on the potential for such sentiment to cause dramatic stock price fluctuations and increase investment risk.The quantification of investment sentiment indicators and the persistent analysis of their impact has been a complex and significant area of research.In this paper,a structured multi-head attention stock index prediction method based adaptive public opinion sentiment vector is proposed.The proposedmethod utilizes an innovative approach to transform numerous investor comments on social platforms over time into public opinion sentiment vectors expressing complex sentiments.It then analyzes the continuous impact of these vectors on the market through the use of aggregating techniques and public opinion data via a structured multi-head attention mechanism.The experimental results demonstrate that the public opinion sentiment vector can provide more comprehensive feedback on market sentiment than traditional sentiment polarity analysis.Furthermore,the multi-head attention mechanism is shown to improve prediction accuracy through attention convergence on each type of input information separately.Themean absolute percentage error(MAPE)of the proposedmethod is 0.463%,a reduction of 0.294% compared to the benchmark attention algorithm.Additionally,the market backtesting results indicate that the return was 24.560%,an improvement of 8.202% compared to the benchmark algorithm.These results suggest that themarket trading strategy based on thismethod has the potential to improve trading profits. 展开更多
关键词 Public opinion sentiment structured multi-head attention stock index prediction deep learning
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Risk management of stock index futures
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作者 Lü Xiaorong Wang Fusheng Wang Hongbao(School of Management, Harbin Institute of Technology, Harbin 150001, China) 《Journal of Southeast University(English Edition)》 EI CAS 2008年第S1期191-195,共5页
The Hong Kong Hang Seng index futures is taken as a study object and a method of empirical analysis is adopted in order to verify the validity of the application of the value-at-risk (VaR) method in the risk measureme... The Hong Kong Hang Seng index futures is taken as a study object and a method of empirical analysis is adopted in order to verify the validity of the application of the value-at-risk (VaR) method in the risk measurement of the stock index futures market. The results suggest that under normal market conditions it is feasible to apply the VaR method in the measurement of the market risks of stock index futures. The daily VaR value of the stock index futures provides a foreseeable profit and loss of the stock index futures. Financial supervisors can adjust their supervising strategies according to the daily VaR value. The speculators can adjust risk capital reserve rates in the same way. The application of this method in China's stock index futures market requires the solutions to specific problems: the absence of historical data, the difficult confirmation of non-risk interest rates etc. 展开更多
关键词 value-at-risk (VaR) method risk management stock index futures (SIF)
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Cost-benefit analysis of trading strategies in the stock index futures market
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作者 Xiong Xiong Yian Cui +2 位作者 Xiaocong Yan Jun Liu Shaoyi He 《Financial Innovation》 2020年第1期628-644,共17页
With the introduction of many derivatives into the capital market,including stock index futures,the trading strategies in financial markets have been gradually enriched.However,there is still no theoretical model that... With the introduction of many derivatives into the capital market,including stock index futures,the trading strategies in financial markets have been gradually enriched.However,there is still no theoretical model that can determine whether these strategies are effective,what the risks are,and how costly the strategies are.We built an agent-based cross-market platform that includes five stocks and one stock index future,and constructed an evaluation system for stock index futures trading strategies.The evaluation system includes four dimensions:effectiveness,risk,occupation of capital,and impact cost.The results show that the informed strategy performs well in all aspects.The risk of the technical strategy is relatively higher than that of the other strategies.Moreover,occupation of capital and impact cost are both higher for the arbitrage strategy.Finally,the wealth of noise traders is almost lost. 展开更多
关键词 Trading strategy stock index futures Agent-based model Cost-benefit analysis
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Optimal Hedging Strategies of Stock Index Futures Based on the Perspective of Information Asymmetry
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作者 Jianhua Guo 《Open Journal of Applied Sciences》 2020年第2期15-24,共10页
Based on two different risk measurement criteria, this article studied the optimal hedging strategies of stock index futures in the case of asymmetric information, and discussed the influence of insider information on... Based on two different risk measurement criteria, this article studied the optimal hedging strategies of stock index futures in the case of asymmetric information, and discussed the influence of insider information on the hedging effect. Through simulation analysis, it can be shown that hedging people with insider information can save hedging costs to a certain extent, which also explains the reason why investors try to obtain corporate information in actual investment activities. 展开更多
关键词 stock index FUTURES OPTIMAL HEDGING Strategy Information Asymmetry
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Stock index adjustments, analyst coverage and institutional holdings: Evidence from China 被引量:7
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作者 Song Zhu Xiaoyu Jiang +1 位作者 Xiaoli Ke Xiaoyu Bai 《China Journal of Accounting Research》 2017年第3期281-293,共13页
Using 231 pairs of matched firms from 2009 to 2012 in Chinese stock market,we find that the stock index adjustment significantly affects the analyst coverage, which in addition to the stock index leads to more analyst... Using 231 pairs of matched firms from 2009 to 2012 in Chinese stock market,we find that the stock index adjustment significantly affects the analyst coverage, which in addition to the stock index leads to more analyst coverage, while deletion from the stock index has no significant effect, indicating that stock index adjustment can significantly change the information environments of firms that are added to the index. An index adjustment also affects institutional holdings in consideration of new information(e.g., changes in fundamentals and information environments). Changes in institutional holdings are partially due to changes in analyst coverage, and both index funds and other types can change their portfolios in response to changes in the target firms' informativeness. 展开更多
关键词 stock index adjustment Analyst coverage Institutional holding
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Profit Guided or Statistical Error Guided? A Study of Stock Index Forecasting Using Support Vector Regression 被引量:1
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作者 HU Zhongyi BAO Yukun +1 位作者 CHIONG Raymond XIONG Tao 《Journal of Systems Science & Complexity》 SCIE EI CSCD 2017年第6期1425-1442,共18页
Stock index forecasting has been one of the most widely investigated topics in the field of financial forecasting. Related studies typically advocate for tuning the parameters of forecasting models by minimizing learn... Stock index forecasting has been one of the most widely investigated topics in the field of financial forecasting. Related studies typically advocate for tuning the parameters of forecasting models by minimizing learning errors measured using statistical metrics such as the mean squared error or mean absolute percentage error. The authors argue that statistical metrics used to guide parameter tuning of forecasting models may not be meaningful, given the fact that the ultimate goal of forecasting is to facilitate investment decisions with expected profits in the future. The authors therefore introduce the Sharpe ratio into the process of model building and take it as the profit metric to guide parameter tuning rather than using the commonly adopted statistical metrics. The authors consider three widely used trading strategies, which include a na¨?ve strategy, a filter strategy and a dual moving average strategy, as investment scenarios. To verify the effectiveness of the proposed profit guided approach, the authors carry out simulation experiments using three global mainstream stock market indices. The results show that profit guided forecasting models are competitive, and in many cases produce significantly better performances than statistical error guided models. This implies thatprofit guided stock index forecasting is a worthwhile alternative over traditional stock index forecasting practices. 展开更多
关键词 Financial market investment trading strategy parameter optimization stock index forecasting support vector regression
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Stock index adjustments and analysts' forecast optimism:A quasi-natural experiment on the CSI 300 Index
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作者 Shangkun Liang Huaigu Cui Chun Yuan 《China Journal of Accounting Research》 2022年第3期28-56,共29页
As stock index adjustments comprise a basic system of capital market,their potential influence on analysts’earnings forecasts is worthy of research.Based on a research sample of 23 adjustments to the CSI 300 Index fr... As stock index adjustments comprise a basic system of capital market,their potential influence on analysts’earnings forecasts is worthy of research.Based on a research sample of 23 adjustments to the CSI 300 Index from June 2007 to June 2018 and the backup stocks announced during the same period,this study examines the impact of additions to stock index on analysts’forecast optimism using a staggered difference-in-differences model.The research results show that after stocks are added to the stock index,analysts’earnings forecast optimism about these stocks increases significantly.Cross-sectional analysis indicates that this increase is more significant when the market is bullish,institutional ownership is low,the ratio of listed brokerage firms is low,star analyst coverage is low,firms show seasoned equity offering activity,the ratio of analysts from the top five brokerage firms ranked by commission income is high,and the analysts’brokerage firms are shareholders.However,analystlevel tests find that analysts’ability helps to reduce the impact of additions to stock index on earnings forecast optimism.Furthermore,additions to stock index significantly increase analyst coverage and forecast divergence.Economic consequences tests find additions to stock index significantly increases stock price synchronization,which is partly mediated by analysts’earnings forecast optimism.This study enriches the literature on the impact of basic capital market systems and analyst behavior.The findings suggest that investors should rationally evaluate analysts’earnings forecasts for stocks added to the stock index and obtain further information from various channels to improve asset allocation efficiency. 展开更多
关键词 stock index adjustments Backup stocks Analyst forecasts OPTIMISM stock price synchronization
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The Different Performance of the Stock Market Indexes of the Three Countries in Different International Events
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作者 Ziying Chen 《Psychology Research》 2023年第7期302-311,共10页
During the period of different changes in the global situation,the stock indexes of China,the United States,and the United Kingdom all showed different trends.Overall,during the outbreak of the epidemic,they all recei... During the period of different changes in the global situation,the stock indexes of China,the United States,and the United Kingdom all showed different trends.Overall,during the outbreak of the epidemic,they all received a huge impact,and due to the different policies and coping strategies of various countries,the follow-up performance also varies greatly.Brexit has only had a slight impact on the British domestic market in a short period time,and China and the United States have prepared for investment in the new market after Brexit,which has also caused the corresponding market index to perform better before the follow-up.Due to the differences in the main market targets and the differences in the geographical location of countries,the negative impact on the British market was more obvious during the Russia-Ukraine conflict,while the stock indexes of China and the United States were relatively stable and even showed an upward trend.It can be seen from the data analysis that the markets in different countries are affected by time differently.With the growing correlation between the markets of various countries,investors should pay more attention to the global situation and the policy orientation of different countries.Considering risk diversification while taking policy dividends helps to obtain stable returns. 展开更多
关键词 COVID-19 Brexit stock index global economic Russian-Ukraine conflict
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Analysis of Financial Derivatives by Mechanical Method (Ⅰ)——Basic Equation of Price of Index Futures 被引量:15
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作者 云天铨 《应用数学和力学》 CSCD 北大核心 2001年第1期104-110,共7页
Similar to the method of continuum mechanics, the variation of the price of index futures is viewed to be continuous and regular. According to the characteristic of index futures, a basic equation of price of index fu... Similar to the method of continuum mechanics, the variation of the price of index futures is viewed to be continuous and regular. According to the characteristic of index futures, a basic equation of price of index futures was established. It is a differential equation, its solution shows that the relation between time and price forms a logarithmic circle. If the time is thought of as the probability of its corresponding price, then such a relation is perfectly coincided with the main assumption of the famous formula of option pricing, based on statistical theory, established by Black and Scholes, winner of 1997 Nobel’ prize on economy. In that formula, the probability of price of basic assets (they stand for index futures here) is assummed to be a logarithmic normal distribution. This agreement shows that the same result may be obtained by two analytic methods with different bases. However, the result, given by assumption by Black_Scholes, is derived from the solution of the differential equation. 展开更多
关键词 金融衍生产品 期货 股票指数期货(期指) Black-Sholes模型 微分方程
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Using Feed Forward BPNN for Forecasting All Share Price Index
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作者 Donglin Chen Dissanayaka M. K. N. Seneviratna 《Journal of Data Analysis and Information Processing》 2014年第4期87-94,共8页
Use of artificial neural networks has become a significant and an emerging research method due to its capability of capturing nonlinear behavior instead of conventional time series methods. Among them, feed forward ba... Use of artificial neural networks has become a significant and an emerging research method due to its capability of capturing nonlinear behavior instead of conventional time series methods. Among them, feed forward back propagation neural network (BPNN) is the widely used network topology for forecasting stock prices indices. In this study, we attempted to find the best network topology for one step ahead forecasting of All Share Price Index (ASPI), Colombo Stock Exchange (CSE) by employing feed forward BPNN. The daily data including ASPI, All Share Total Return Index (ASTRI), Market Price Earnings Ratio (PER), and Market Price to Book Value (PBV) were collected from CSE over the period from January 2nd 2012 to March 20th 2014. The experiment is implemented by prioritizing the number of inputs, learning rate, number of hidden layer neurons, and the number of training sessions. Eight models were selected on basis of input data and the number of training sessions. Then the best model was used for forecasting next trading day ASPI value. Empirical result reveals that the proposed model can be used as an approximation method to obtain next day value. In addition, it showed that the number of inputs, number of hidden layer neurons and the training times are significant factors that can be affected to the accuracy of forecast value. 展开更多
关键词 Artificial Neural Networks (ANNs) FEED FORWARD Back Propagation (BP) stock index Forecasting
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Model for stock-recruitment dynamics of the Peruvian anchoveta (<i>Eugraulis ringens</i>) off Peru 被引量:2
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作者 Ashneel A. Singh Kazumi Sakuramoto Naoki Suzuki 《Agricultural Sciences》 2014年第2期140-151,共12页
This paper was aimed at re-examining the validity of the results from Cahuin et al. (Estuar. Coast. Shelf Sci. 84, 2009) and identifying a model to describe the stock-recruitment relationship of the Peruvian anchoveta... This paper was aimed at re-examining the validity of the results from Cahuin et al. (Estuar. Coast. Shelf Sci. 84, 2009) and identifying a model to describe the stock-recruitment relationship of the Peruvian anchoveta (Eugraulis ringens). Regression analysis was used to determine if density-dependent effects were present. The analysis did not show the existence of any densitydependent effects. It is important to use environmental factors and take observational and process errors into account when attempting to identify density-dependent effects in fish populations. Sea surface temperature (SST) and Southern Oscillation Index (SOI) were used as independent variables to fit the recruitment dynamics of the anchoveta. Both SST and SOI were found to be significantly important parameters in structuring anchoveta dynamics according to Akaike Information Criterion (AIC) and R2 values. The results of this study do not correlate with the findings of Cahuin et al., (2009), where density-dependent effects and the presence of regimes were detected. In conclusion, the recruitment Rt is essentially determined in proportion to spawning stock biomass St, and then environmental factors in year t further change the recruitments. This mechanism is completely same with that for Japanese sardine proposed by Sakuramoto (The Open Fish. Sci. 5, 2012). 展开更多
关键词 Anchoveta DENSITY-DEPENDENT Recruitment Regimes REPRODUCTIVE Success Sea Surface Temperature Southern Oscillation index SPAWNING stock Biomass
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The Changes in World Oil Prices, Monetary Factors, and Foreign Index Toward Composite Index Movement: Indonesian Case for the Period of 2005-2011
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作者 Darmawan Achmad Ishak Ramli 《Journal of Modern Accounting and Auditing》 2013年第9期1263-1274,共12页
Capital market is one of the drivers of the economy through the formation of capital investor excess as well as an indicator of a country's economy. Movement of stock price index is often influenced by many factors, ... Capital market is one of the drivers of the economy through the formation of capital investor excess as well as an indicator of a country's economy. Movement of stock price index is often influenced by many factors, derived from the company's performance, monetary factor, and changes in world oil prices. This study highlights the problem in world oil prices due to political turmoil in the Middle East. The samples are taken from the Jakarta Composite Stock Price Index (JCI), oil prices, Indonesian inflation rate, Certificate of Bank Indonesia's (CBI) rate, and the reserve assets, during the period from January 2005 to December 2011 (84 months). Using the data published by the Bank of Indonesia, reports of the Central Bureau of Statistics (Biro Pusat Statistik, BPS), and other relevant sources, the data analyzed through the Eviews 7.1. The main objective of this study is to examine the effect of oil prices, foreign stock price index, and monetary variables (inflation rate, CBI rate, country's foreign reserves, and others) toward the JCI analyzed through the error correction model (ECM). Hypothesis testing with the F-test for the 95% confidence level indicates that the oil price, exchange rate (Indonesian Rupiah (IDR)/United States Dollar (USD)), CBI rate, foreign exchange reserves, the Dow Jones Index, and the Taiwan stock index, both simultaneously as well as partially have a significant influence on the JCI. 展开更多
关键词 Jakarta Composite stock Price index (1CI) world oil prices country's foreign reserves IndonesianRupiah (IDR) foreign stock prices
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Empirical Test of "Barometer Function" of China's Stock Market
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作者 孙开连 王凯涛 从臻 《成组技术与生产现代化》 2002年第1期40-43,60,共5页
Through the empirical test of the economic and stock market price index from 1994-2001.6, this article finds that the price tendency of the stock market in China could reflect the economic status and the future trend,... Through the empirical test of the economic and stock market price index from 1994-2001.6, this article finds that the price tendency of the stock market in China could reflect the economic status and the future trend, thus has the function of barometer, additionally through the normal analysis of the continuing falling of the stock price since July 2001, so, the paper comes to the conclusion that the falling price is the reflection of the weak macro economy and the accelerating recession of the industries, and therefore is a warning of the possible worsened economic tendency. Suggestions are to adjust the macro fiscal and financial policy to prevent the economy from recessing. By the way the article conducts some of the primary analyses of punishments against market defiance and reducing state owned shares, thus to clarify some of the unclear concepts and prevent the misleading of economic adjust ment. 展开更多
关键词 中国 证券市场 经济晴雨表 宏观经济 股票价格指数
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The Problems Being Faced for Establishing Index Futures Transaction and the Contract Design
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作者 李朝民 《成组技术与生产现代化》 2003年第4期44-47,共4页
The article deeply and systematically probed into a series of problems being faced for establishing index futures transaction in China. Drawing on the successful experiences of other relative countries and according t... The article deeply and systematically probed into a series of problems being faced for establishing index futures transaction in China. Drawing on the successful experiences of other relative countries and according to Chinese real conditions, the author chooses Shanghai composite index as subject-matter, and has designed an index futures contract that accord with the situation of China. 展开更多
关键词 股票指数 期货市场 合同 股指期货 中国
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存量地下空间更新价值评估体系研究
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作者 胡斌 李雨姗 张明子 《地下空间与工程学报》 CSCD 北大核心 2024年第1期17-22,41,共7页
存量地下空间在补充地面空间资源、完善城市设施方面具有巨大的潜力,但在发展过程中凸显出功能集聚但空间匮乏、品质参差且风貌缺失、功能错位且动迁成本高、停车供给不足又缺乏联动等众多问题。因其自身特点复杂且受到的限制较多,如对... 存量地下空间在补充地面空间资源、完善城市设施方面具有巨大的潜力,但在发展过程中凸显出功能集聚但空间匮乏、品质参差且风貌缺失、功能错位且动迁成本高、停车供给不足又缺乏联动等众多问题。因其自身特点复杂且受到的限制较多,如对于公众开放性不足,涉及多个发展目标,影响方案决策的因素较多,以及配套管理机制滞后等,加之缺乏高效的价值评估方法,导致在对其进行更新再利用时面临利用方式的单一和利用效率的不足。本文从全要素研究分析的角度出发,以现状质量、更新需求、成本投入和可获效益4个需求准则进行价值评估指标的选取,经过对多种评估方法的对比,选用特征价格法用于城市存量地下空间价值评估,以存量地下空间更新的微观形成机制估算潜在价值,采用定性分析与定量评价相结合的方式,在重要因素与更新利用之间建立回归模型,选择拟合度较好的半对数模型,并提出借助多元数据,提高评估的准确性,拟合存量地下空间的更新价值分布,以期为存量地下空间的高效、高品质更新利用提供参考。 展开更多
关键词 地下空间 存量更新 价值评估 指标选取 多元数据
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城市街区单元绿地空间格局与植物群落碳汇效益优化研究
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作者 王晶懋 王一凡 +2 位作者 张涛 范李一璇 孙婷 《风景园林》 北大核心 2024年第6期37-45,共9页
【目的】目前城市绿地已经进入存量发展阶段,如何在城市有限绿地空间条件下实现“碳中和”目标,合理布局低碳绿地空间格局,科学配置植物群落以增加生物多样性,成为目前城市绿地碳汇效益研究的重点和难点。【方法】以西安市碑林区和沣西... 【目的】目前城市绿地已经进入存量发展阶段,如何在城市有限绿地空间条件下实现“碳中和”目标,合理布局低碳绿地空间格局,科学配置植物群落以增加生物多样性,成为目前城市绿地碳汇效益研究的重点和难点。【方法】以西安市碑林区和沣西新城的城市绿地空间格局为研究对象,对研究区域内街区单元的绿地空间格局进行分析并分类,探索街区单元绿地空间格局与碳汇量化关系,并从平面布局和垂直结构两方面提出城市街区单元绿地碳汇效益的优化方法,并选取碳储量最低的单核心辐射型街区单元的3个绿地样方进行碳汇效益优化设计。【结果】总结出4种西安市典型城市街区单元绿地空间格局模式,明晰了碳储量分布特征以及绿地空间格局对碳储量的影响机制,提出了城市街区单元绿地空间格局碳汇效益优化方法,发现碳储量与斑块类型面积(CA)、景观形状指数(LSI)呈极显著正相关关系,与聚集度(AI)呈极显著负相关关系。各类绿地空间格局碳储量大小为多核心辐射型>散点分布型或廊道穿越型>单核心辐射型,建议在单核心辐射型街区单元优化中增加植物群落层次结构,并增加高固碳植物种类及数量,提升样方内年固碳量。【结论】从中观尺度讨论街区单元绿地空间格局与植物群落碳汇效益之间的关系,使城市中小尺度绿地发挥应有的生态系统服务功能,探索街区单元绿地空间格局的构成要素与设计方法,为低碳绿地设计提供参考,提升城市街区单元内社区生活圈的人居环境质量。 展开更多
关键词 城市街区单元 绿地空间格局 景观格局指数 碳储量 碳汇效益 植物群落设计 陕西西安
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基于PLUS和InVEST模型的合肥市生态系统碳储量时空演变特征 被引量:6
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作者 智菲 周振宏 +1 位作者 赵铭 王诗琪 《水土保持学报》 CSCD 北大核心 2024年第2期205-215,共11页
[目的]为寻求“双碳”目标导向下的合肥市城市发展新方案。[方法]依据合肥市2000-2020年5期土地利用数据,在合肥市国土空间规划指引下,运用PLUS模型模拟得到2035年合肥市土地利用时空演变规律,耦合InVEST模型探究多情景下合肥市碳储量... [目的]为寻求“双碳”目标导向下的合肥市城市发展新方案。[方法]依据合肥市2000-2020年5期土地利用数据,在合肥市国土空间规划指引下,运用PLUS模型模拟得到2035年合肥市土地利用时空演变规律,耦合InVEST模型探究多情景下合肥市碳储量时空变化特征,并进一步挖掘土地综合利用程度对碳储量的影响。[结果](1)2000-2020年合肥市土地利用变化特征主要表现为耕地、林地减少,其中耕地为建设用地扩增主要来源。自然发展和农田资源保护情景的土地变化规律大致相同,主要表现为耕地、林地、水体减少;绿色汇增城市发展情景下,林地相比其余2个情景面积由减少转为增加。(2)2000-2020年合肥市碳储量逐年递减,其中2005-2010年碳损失最为剧烈。到2035年,自然发展情景、农田资源保护情景、绿色汇增城市发展情景碳储量分别为138.96×10^(6),140.13×10^(6),139.81×10^(6) t。农田资源保护情景下,碳储量明显增加区域最低,建设用地扩张减缓;绿色汇增城市发展情景下,林地由碳损失转为碳固持,是最具固碳潜力的发展趋势。(3)绿色汇增城市发展情景土地利用率最高,可有效降低土地综合利用程度对碳储量流失的威胁。[结论]农田资源保护情景与绿色汇增城市发展情景均有助于城市固碳发展,实施生态保护与城市发展并行政策,调整土地综合利用模式有助于改善城市碳流失。 展开更多
关键词 InVEST模型 PLUS模型 碳储量 土地利用程度综合指数
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饲养密度对笼养白羽肉鸡生长性能、羽毛评分、血清生化和免疫指标的影响
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作者 沈杰 吴洪 +3 位作者 杨海明 仲向前 王迎春 张银娣 《中国家禽》 北大核心 2024年第8期86-92,共7页
试验旨在探究不同饲养密度对笼养白羽肉鸡生长性能、羽毛评分、血清生化和免疫指标的影响。试验选取504只体重相近、健康状况良好的1日龄科宝白羽肉鸡母雏,随机分为3组,每组8个重复(笼)。7~14日龄3组饲养密度分别为16只/m^(2)、17只/m^... 试验旨在探究不同饲养密度对笼养白羽肉鸡生长性能、羽毛评分、血清生化和免疫指标的影响。试验选取504只体重相近、健康状况良好的1日龄科宝白羽肉鸡母雏,随机分为3组,每组8个重复(笼)。7~14日龄3组饲养密度分别为16只/m^(2)、17只/m^(2)、18只/m^(2),15~39日龄3组饲养密度为13只/m^(2)、14只/m^(2)、15只/m^(2)。结果显示:(1)不同饲养密度对7~14日龄和15~28日龄肉鸡平均采食量和料重比产生显著影响(P<0.05),且15~28日龄时,14只/m^(2)组平均日增重显著高于13只/m^(2)组(P<0.05),13只/m^(2)组料重比显著高于15只/m^(2)组(P<0.05)。29~39日龄13只/m^(2)组和14只/m^(2)组平均日增重显著高于15只/m^(2)(P<0.05);(2)不同饲养密度对肉鸡14日龄主翼羽长度产生显著影响(P<0.05);(3)不同饲养密度对肉鸡14日龄和39日龄羽毛评分产生显著影响(P<0.05);(4)不同饲养密度对肉鸡血清中碱性磷酸酶(ALP)活力、三碘甲状腺原氨酸(T3)和甲状腺素(T4)的含量产生显著影响(P<0.05),17只/m^(2)组显著高于16只/m^(2)组和18只/m^(2)组(P<0.05),14只/m^(2)组显著高于13只/m^(2)组和15只/m^(2)组(P<0.05);(5)不同饲养密度对肉鸡14日龄和39日龄血清中白细胞介素-4(IL-4)、白细胞介素-6(IL-6)、白细胞介素-10(IL-10)和白细胞介素-1β(IL-1β)含量产生显著影响(P<0.05)。研究表明,笼养科宝白羽肉鸡7~14日龄适宜饲养密度为17只/m^(2),15~39日龄适宜饲养密度为14只/m^(2)。 展开更多
关键词 饲养密度 白羽肉鸡 生长性能 血清生化指标 抗氧化能力 免疫指标
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基于CBAMs-BiLSTM模型的中国股市预测
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作者 崔晨豪 李勇 《中国科学技术大学学报》 CAS CSCD 北大核心 2024年第2期48-61,I0005,I0006,共16页
卷积块注意力模块(CBAM)因其可以有效地提高深度学习模型的预测准确性从而在各种预测问题中显示了其优越性。然而,CBAM在股指预测问题中的有效性研究却十分有限。为了解决这个问题并提高股指的预测精度,本文提出了CBAMs-BiLSTM模型。它... 卷积块注意力模块(CBAM)因其可以有效地提高深度学习模型的预测准确性从而在各种预测问题中显示了其优越性。然而,CBAM在股指预测问题中的有效性研究却十分有限。为了解决这个问题并提高股指的预测精度,本文提出了CBAMs-BiLSTM模型。它将多个CBAM与双向长短期记忆网络(BiLSTM)相结合。研究中,标准指标评价法(SME)和模型置信集检验(MCS)用于综合评价模型的优越性和稳健性。实验数据为具有代表性的中国股指数据集:上证综合指数和深证综合指数。数值结果表明,CBAMs-BiLSTM优于单独的BiLSTM。其中在MAE,RMSE和MAPE上分别平均降低了13.06%,13.39%和12.48%。这证实了CBAM可以有效地提高BiLSTM的预测精度。此外,通过与其他流行模型进行对比,并研究了改变数据集、预测方法和训练集的大小的影响。结果一致证实了CBAMs-BiLSTM在预测精度和投资回报方面的优越性和稳健性。 展开更多
关键词 股指预测 双向长短期记忆网络 卷积块注意力模块 模型置信集检验 标准指标评价法
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VAE-ATTGRU模型的股指期货价格预测研究
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作者 张玉婷 金传泰 李勇 《计算机工程与应用》 CSCD 北大核心 2024年第17期293-301,共9页
针对股指期货市场高波动、非平稳、非线性和高信噪比等特性造成的预测难度大的问题,利用变分自编码器(VAE)和循环神经网络(RNN)提出一种基于VAE-ATTGRU的混合深度学习股指期货价格预测模型。利用变分自编码器对股指期货技术指标进行学习... 针对股指期货市场高波动、非平稳、非线性和高信噪比等特性造成的预测难度大的问题,利用变分自编码器(VAE)和循环神经网络(RNN)提出一种基于VAE-ATTGRU的混合深度学习股指期货价格预测模型。利用变分自编码器对股指期货技术指标进行学习,将VAE学习到的潜在因子与原始数据融合实现数据增强,得到更丰富的因子表示;使用循环神经网络对股指期货价格进行预测,发现结合了注意力机制的门控循环单元(ATTGRU)可以对VAE增强后的股指期货数据进行充分学习,对关键特征信息进行捕捉并重新赋予权重。在沪深300股指期货、中证500股指期货和上证50股指期货数据上进行实验,通过均方根误差(RMSE)、平均绝对误差(MAE)、平均绝对百分比误差(MAPE)和决定系数R2对VAE-ATTGRU模型进行评估,发现其在预测精度上优于其他模型。 展开更多
关键词 股指期货预测 变分自编码器(VAE) 数据增强 注意力机制 门控循环单元(GRU)
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