Structured Multi-Head Attention Stock Index Prediction Method Based Adaptive Public Opinion Sentiment Vector

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.

A Critical Review of the Effects of Stock Returns and Market Timing on Capital Structure

Capital structure is regarded as the combination of debt and equity firms used to finance operations and investments.The choice of capital structure significantly impacts a company’s cost of capital,profitability,and risk profile.Among a series of factors that affect capital structure,this paper focuses on stock returns and market timing.In this review,an array of papers is analyzed to summarize what current research claims regarding the influence of stock returns and market timing on capital structure.This paper centers on the stock return and market timing theories and also discusses other theories like the trade-off theory,the pecking order theory,and the signaling theory.

Stable isotopic composition of otoliths in identification of stock structure of small yellow croaker(Larimichthys polyactis) in China

Oxygen and carbon isotope ratios（δ^（18）O and δ^（13）C） in otoliths were used to identify the stock structure of small yellow croaker,Larimichthys polyactis.Otoliths were collected from fish at five locations across the Yellow Sea and the Bohai Sea representing most of their distributional range and fisheries areas.The significant differences in the isotopic signatures showed that the five locations could be chemically distinguished and clearly separated,indicating stock subdivision.Correlation of δ^（18）O and δ^（13）C values suggested that population of L.polyactis could be divided into the Bohai Sea group,the southern Yellow Sea group and the central Yellow Sea group.Discriminant analysis of δ^（18）O and δ^（13）C values demonstrated a high significant difference with 85.7% classification accuracy.The spatial separation of L.polyactis indicated a complex stock structure across the Yellow Sea and the Bohai Sea.These results indicate that optimal fisheries management may require a comprehensive consideration on the current spatial arrangements.This study has provided further evidence that measurement of the stable isotopes ratios in otolith can be a valuable tool in the delineation of fishery management units.

Permanence and global attractivity of stage-structured predator-prey model with continuous harvesting on predator and impulsive stocking on prey

We investigate a stage-structured delayed predator-prey model with impulsive stocking on prey and continuous harvesting on predator. According to the fact of biological resource management, we improve the assumption of a predator-prey model with stage structure for predator population that each individual predator has the same ability to capture prey. It is assumed that the immature and mature individuals of the predator population are divided by a fixed age, and immature predator population does not have the ability to attach prey. Sufficient conditions are obtained, which guarantee the global attractivity of predator-extinction periodic solution and the permanence of the system. Our results show that the behavior of impulsive stocking on prey plays an important role for the permanence of the system, and provide tactical basis for the biological resource management. Numerical analysis is presented to illuminate the dynamics of the system.

Evaluation of the performance of alternative assessment configurations to account for the spatial heterogeneity in age-structure: a simulation study based on Indian Ocean albacore tuna

Various population structures or spatial heterogeneities in population distribution have been an important source of model misspecification and have had an impact on estimation performance in fisheries stock assessment.In this study,we simulated the Indian Ocean albacore spatial heterogeneity in age-structure using Stock Synthesis according to the stage-dependent migration rate and region-dependent fishing mortality rate and generated the stock assessment data.Based on these data,we investigated the performances of different spatial configurations,selectivity curves and selections of CPUE(catch per unit effort)indices of the assessment models which were used to account for spatial heterogeneity.The results showed:(1)although the spatially explicit configurations,which exactly matched the operating model,provided unbiased and accurate estimates of relative spawning biomass,relative fishing mortality rate and maximum sustainable yield in all simulation scenarios,their performance may be very poor if there were mismatches between them and the operating model due to gaps in knowledge and data;(2)for spatially explicit assessment configuration,the correct boundary was required,but for non-spatially explicit assessment configuration,it seemed more important for analysts to partition the area to properly reflect the transition in field data and to effectively account for the impacts of ignoring the spatial structure by using the additional spatially referenced parameters;(3)although the areas-as-fleets methods and flexible time-varying selectivity curves could be used as better alternative approaches to account for spatial structure,these configurations could not completely eliminate the impacts of model misspecification and the quality of estimates of different quantities from the same assessment model may be inconsistent or the performance of the same assessment configuration may fluctuate significantly between simulation scenarios;(4)although the worst estimates could generally be avoided by using multiple CPUE indices,there were no best solutions to select or regenerate the CPUE indices to account for the impacts of the ignored spatial structure to obviously improve the quality of stock assessment.Compared with the results of assessment model configurations which are used to account for the spatial structure by different modelers,the performances of the configurations are always casespecific except for spatially explicit configurations which exactly match the operating model.In this sense,our study will not only provide some insights into the current Indian Ocean albacore stock assessment but also enrich existing knowledge regarding the performance of assessment configurations to account for spatial structure.

Capital and Labor Allocation Structure and China's Economic Growth

Using sector-specific growth accounting method, this paper investigates the growth effect of inter-industry allocation of capital and labor in China. This paper has found that existing investment data are classified according to investment entities rather than user entities and directly using such data for the measurement of capital inventory of various sectors will seriously overestimate the capital inventory of tertiary industry and lead to distorted conclusions of "structural burden" of capital allocation and its serious violation of the principle of efficiency. By excluding real estate sector, this paper has found that after the 1990 s, inter-industry capital allocation had been generally consistent with the principle of efficiency and the effect of capital allocation structure is not significant. Our estimates also found that the growth effect arising from the inter-industry allocation of labor since reform and opening up averages 0.63 percentage points, which is significantly positively correlated with residual economic growth rate and residual TFP and demonstrates a decade-long "reform cycle." According to the comparative study on the effect of labor allocation structure of 37 other countries and regions, by 2017, the effect of China's labor allocation structure will continue to remain in a relatively high stage; between 2017 and 2023, structural effect will significantly diminish and deceleration pressure will rise swiftly; after 2030, the effect of labor allocation structure will linger in a low level stage, when economy is likely to enter into a stage of low growth rate. These findings will help us better assess future economic growth tendencies.

我国肉鸡饲料价格波动特征及影响因素分析

文章旨在分析肉鸡价格波动特征及影响因素,有利于推动禽类养殖业健康稳定发展。基于2002年1月-2022年12月我国252个肉鸡饲料企业样本数据,在通过平稳性检验后,采用VAR模型和方差分解法,从肉鸡饲料价格、供给和需求方面分析引起我国肉鸡饲料价格波动的主要因素。结果显示,在供给层面,肉鸡饲料价格波动的主要影响因素为玉米存量和豆粕存量,第7期玉米存量和豆粕存量对当月肉鸡饲料价格的影响占比分别是30.78%和20.39%。在需求层面,在第7期农村居民人均可支配收入和可繁殖母鸡存栏量对肉鸡饲料价格的影响占比较高,分别为9.06%和6.87%。研究表明,肉鸡饲料价格波动受肉鸡饲料自身价格影响程度最大,随后依次为玉米存量、豆粕存量、农村居民人均可支配收入、可繁殖母鸡存栏量、鱼虾肉价格、肉鸡存栏量、牛肉价格和城镇居民人均可支配收入。

2021年山东长岛毗邻海域底层渔业生物监测数据集

近岸岛屿毗邻海域作为陆架边缘海中最具代表性的区域之一,是重要的海-陆过渡区域。在自然环境变动与人类活动的双重影响下,其生态系统具有多样性和复杂性。长岛毗邻海域具有典型的海岛生态环境特征,为渤黄海渔业种类的洄游通道和关键栖息地,对该海域生态系统食物网结构和能流过程具有重要意义。2021年3月至12月,山东长岛近海渔业资源国家野外科学观测研究站在长岛毗邻海域开展10航次,每航次10站的底层渔业生物逐月调查与样品测定。通过对渔获物的生物学测定数据进行计算,获得相对重要性指数(index of relative importance,IRI)、物种更替率、单位捕捞努力量渔获量(catch per unit effort,CPUE)以及包含Margalef丰富度指数(D)、Shannon-Wiener多样性指数(H′)和Pielou均匀度指数(J′)在内的生物多样性指数,构成了本数据集。基于多人全样本交叉复核完成审查与校对过程,确保数据集的规范性与准确性。本数据集可为渤黄海底层渔业生物时空格局和海岛生态系统研究提供数据支撑。

有效资本存量、供需匹配与中国经济稳定增长

在中国高质量发展不断深化的背景下,有效投资通过优化供给结构可实现供给和需求的进一步匹配,进而克服中国现阶段有效供给不足的问题。本文以不同产业资本效率为权重构建了中国有效资本存量指标体系,相比于以往研究,从理论方面对简单加总的资本存量进行了改进。同时,通过结合不同产业的投资效率以及资本占比得出中国投资结构面临的问题。研究发现:中国投资结构面临的问题是低投资效率的产业获得高份额的投资以及高投资效率的产业没有获得足够的投资份额,进而导致中国有效供给不足和内循环不通畅。因此,需要通过增加有效投资来盘活存量资本和优化供给结构,确保实现经济的稳定增长。

基于Cyt b基因的江苏省湖泊鳙群体遗传多样性和遗传结构研究

为了解江苏省湖泊鳙群体遗传资源现状,科学地开展鳙增殖放流,采用线粒体Cyt b基因,分析了6个湖泊群体、223个个体的遗传多样性和遗传结构。结果表明,223条Cyt b序列共有10个变异位点,定义9个单倍型,单倍型多样性(Hd)和核苷酸多样性(Pi)分别为(0.725±0.017)和(0.00191±0.00080),整个鳙群体呈现出高Hd和低Pi的遗传多样性模式。6个群体的单倍型多样性为(0.625±0.077)~(0.771±0.032),核苷酸多样性为(0.00159±0.00027)~(0.00221±0.00011)。分子方差分析结果显示,遗传变异主要来源于群体内部(97.17%),总遗传分化系数(Fst)为0.0283。群体间Fst为-0.0258~0.0907,遗传距离为0.0016~0.0022,表明6个群体间遗传分化水平较低。中性检验结果和错配分布分析表明,鳙群体保持稳定,未经历群体扩张。指出,鳙群体遗传多样性较低,遗传结构趋于同质化,需要采取措施,提高湖泊鳙群体遗传多样性。

企业社会责任、女性高管与股价同步性——基于信息不对称视角的实证研究

基于中国沪深A股上市公司2003—2022年样本数据,实证考察企业社会责任对股价同步性的影响,并检验企业高管性别特征对上述关系的调节作用。研究发现,企业社会责任与股价同步性间存在显著负向影响关系,女性高管的性别特征能够在一定程度上增强企业社会责任对股价同步性的抑制作用。研究从信息传递对股票价格影响的角度出发,对当前企业社会责任、高管性别特征及其对股价波动影响的研究文献进行拓展,有利于完善资本市场会计信息披露和监管,缓解企业内外部信息不对称,对于投资者了解企业特有信息,降低股价同涨同跌的大幅波动,稳定金融市场秩序具有一定的信号传递作用。

资本市场开放与企业ESG表现——基于绿色创新的调节效应

随着首批两项国际财务报告可持续披露准则的正式发布,如何提升企业ESG表现以推进可持续发展成为实务界和理论界的热点议题。利用沪深港通交易机制提供的准自然实验环境,构建多时点双重差分模型以实证检验资本市场开放对企业ESG表现的影响机制。研究发现,沪深港通交易机制的实施通过提高标的企业市场关注度和优化投资者结构改善企业ESG表现,该结论在经过一系列稳健性检验后仍成立,且该政策效应在非国有企业和具有较高信息披露质量企业中更明显。此外,企业开展绿色创新活动可强化资本市场开放对企业ESG表现的提升作用。研究丰富了资本市场开放促进企业可持续发展的经验证据,也为当前企业ESG表现影响因素的探究提供了新的视角。

结构化最大间隔双支持向量机在股票预测中的应用

股票价格受政策、宏观经济以及公司经营状况等多方因素的影响,且各因素之间存在较高的相关性,因此股票数据存在的高噪声、非平稳等特性使得股票预测充满困难。为了减少数据中存在的噪声对股价预测准确性的影响,基于马氏距离的类间隔可分性,提出了结构化最大间隔双支持向量机,其分别针对正类样本和负类样本,寻找两个非平行的超平面,使每一类样本离本类样本的欧式距离尽可能小,同时离异类超平面的马氏距离尽可能大。8组基准数据集的实验结果表明,该方法在含噪声数据的分类问题上具有稳定的准确率,从而提升了模型的预测性能和抗噪能力。同时将其应用到股票涨跌趋势预测中,通过对上证综指、上证A指、上证380指数以及中国平安等14只股票实证分析的结果表明,相较于其他对比模型,结构化最大间隔双支持向量机表现出了较好的预测结果,具有一定的实用价值。

房地产企业资本结构对股价波动的传递效应分析——基于结构化GARCH模型

中国房地产企业资本结构长期处于高负债、高杠杆状态。在二十余年的房地产高速发展过程中,高杠杆风险长期被忽视,甚至被认为是房地产企业发展的固有模式。在结构化GARCH模型中引入资本结构因素,检验房地产企业资本结构对股价波动的传递与溢出效应。研究发现:中国房地产市场具有结构化特征,杠杆乘数与股价波动具有同步性;过高的负债水平并不会提升房地产企业的规模效应,反而会抑制股票收益率的增长。

铁路防溜器具应用现状及标准化问题研究

防溜器具是为避免机车车辆在停留状态下发生溜逸而使用的重要技术设备,主要包括防溜铁鞋、防溜枕木等。国铁集团技术规章对防溜器具在配备、使用及管理方面均作出了相关规定。目前,防溜铁鞋在铁路行业和企业层面均制定了技术标准,但行业标准实施时间较早,在一定程度上已不适应现场技术设备发生的变化,而防溜枕木在铁路行业和企业层面均无技术标准,现场缺少指导性技术文件。针对上述问题,通过对各铁路局集团公司和生产厂家的调研,研究分析现场在使用和管理防溜铁鞋和防溜枕木过程中存在的问题,提出对防溜器具和相应技术标准的建议,为后续开展技术标准的制修订提供支撑。

社会保障视角下人口年龄结构与股票市场价格研究

文章首先对社会保障、人口年龄结构与股票市场价格关系进行文献梳理,而后进行理论分析,力求明晰社会保障、人口年龄结构与股票市场价格的内在逻辑。研究发现,低中高龄人群占比对股票价格影响不一;社会保障水平提高将推高股票市场价格,但该影响在不同年龄群体间存在差异。一是作为理论研究的拓展;二是结合中国现状,进一步就人口政策选择如何影响中国股票市场进行探究,为政策选择提供借鉴和指导;三是社会保障作为一种财政政策的工具,关于社会保障与人口年龄结构、股票价格的研究,有助于政府部门利用社会保障这一财政工具对金融市场特别是股票市场进行调节。

地铁车辆段超长结构温度应力分析及裂缝控制

为了研究超长结构在温度作用下产生的温度应力及其裂缝控制,基于济南轨道交通R2线王府庄车辆段的工程设计案例,采用YJK软件对盖板进行了温度应力分析。结果表明,与嵌固端相连的一层盖板受温度作用的影响较大,刚度较大的运用库区受温度作用的影响更显著。同时给出了在工程中控制裂缝的措施,如采用预应力技术和附加温度钢筋,实践证明,此方法取得了良好的裂缝控制效果。

COVID‑19 and instability of stock market performance:evidence from the U.S.

The effect of COVID-19 on stock market performance has important implications for both financial theory and practice.This paper examines the relationship between COVID-19 and the instability of both stock return predictability and price volatility in the U.S over the period January 1st,2019 to June 30th,2020 by using the methodologies of Bai and Perron(Econometrica 66:47–78,1998.https://doi.org/10.2307/2998540;J Appl Econo 18:1–22,2003.https://doi.org/10.1002/jae.659),Elliot and Muller(Optimal testing general breaking processes in linear time series models.University of California at San Diego Economic Working Paper,2004),and Xu(J Econ 173:126–142,2013.https://doi.org/10.1016/j.jecon om.2012.11.001).The results highlight a single break in return predictability and price volatility of both S&P 500 and DJIA.The timing of the break is consistent with the COVID-19 outbreak,or more specifically the stock sellingoffs by the U.S.senate committee members before COVID-19 crashed the market.Furthermore,return predictability and price volatility significantly increased following the derived break.The findings suggest that the pandemic crisis was associated with market inefficiency,creating profitable opportunities for traders and speculators.Furthermore,it also induced income and wealth inequality between market participants with plenty of liquidity at hand and those short of funds.