A Bayesian regularized artificial neural network for stock market forecasting

In this paper a Bayesian regularized artificial neural network is proposed as a novel method to forecast financial market behavior. Daily market prices and financial technical indicators are utilized as inputs to predict the one day future closing price of individual stocks. The prediction of stock price movement is generally considered to be a challenging and important task for financial time series analysis. The accurate prediction of stock price movements could play an important role in helping investors improve stock returns. The complexity in predicting these trends lies in the inherent noise and volatility in daily stock price movement. The Bayesian regularized network assigns a probabilistic nature to the network weights, allowing the network to automatically and optimally penalize excessively complex models. The proposed technique reduces the potential for overfitting and overtraining, improving the prediction quality and generalization of the network. Experiments were performed with Microsoft Corp. and Goldman Sachs Group Inc. stock to determine the effectiveness of the model. The results indicate that the proposed model performs as well as the more advanced models without the need for preprocessing of data, seasonality testing, or cycle analysis.     

A turning point prediction method of stock price based on RVFL-GMDH and chaotic time series analysis

Stock market prediction is extremely important for investors because knowing the future trend of stock prices will reduce the risk of investing capital for profit. Therefore, seeking an accurate, fast, and effective approach to identify the stock market movement is of great practical significance. This study proposes a novel turning point prediction method for the time series analysis of stock price. Through the chaos theory analysis and application, we put forward a new modeling approach for the nonlinear dynamic system. The turning indicator of time series is computed firstly; then, by applying the RVFL-GMDH model, we perform the turning point prediction of the stock price, which is based on the fractal characteristic of a strange attractor with an infinite self-similar structure. The experimental findings confirm the efficacy of the proposed procedure and have become successful for the intelligent decision support of the stock trading strategy.

     

Market Price Effects of Data Security Breaches

ABSTRACT

This study examines the impact of reported breaches in computer security using event study analysis. We use the event-study methodology to measure the magnitude of the effect of data security breach events on the behavior of stock markets. Our data come from security breaches spanning a ten-year period and involving various industries. The findings of the study suggest that there exist abnormal negative stock price returns following the announcement of a breach. Such abnormal negative returns persist over the next several years. Moreover, the source of data breach may moderate the price effect; the market tends to punish more heavily those compromises that could have been avoided with reasonable precautions by the breached company.     

A two-stage architecture for stock price forecasting by integrating self-organizing map and support vector regression

Stock price prediction has attracted much attention from both practitioners and researchers. However, most studies in this area ignored the non-stationary nature of stock price series. That is, stock price series do not exhibit identical statistical properties at each point of time. As a result, the relationships between stock price series and their predictors are quite dynamic. It is challenging for any single artificial technique to effectively address this problematic characteristics in stock price series. One potential solution is to hybridize different artificial techniques. Towards this end, this study employs a two-stage architecture for better stock price prediction. Specifically, the self-organizing map (SOM) is first used to decompose the whole input space into regions where data points with similar statistical distributions are grouped together, so as to contain and capture the non-stationary property of financial series. After decomposing heterogeneous data points into several homogenous regions, support vector regression (SVR) is applied to forecast financial indices. The proposed technique is empirically tested using stock price series from seven major financial markets. The results show that the performance of stock price prediction can be significantly enhanced by using the two-stage architecture in comparison with a single SVR model.     

Stock Trading Using RSPOP: A Novel Rough Set-Based Neuro-Fuzzy Approach

This paper investigates the method of forecasting stock price difference on artificially generated price series data using neuro-fuzzy systems and neural networks. As trading profits is more important to an investor than statistical performance, this paper proposes a novel rough set-based neuro-fuzzy stock trading decision model called stock trading using rough set-based pseudo outer-product (RSPOP) which synergizes the price difference forecast method with a forecast bottleneck free trading decision model. The proposed stock trading with forecast model uses the pseudo outer-product based fuzzy neural network using the compositional rule of inference [POPFNN-CRI(S)] with fuzzy rules identified using the RSPOP algorithm as the underlying predictor model and simple moving average trading rules in the stock trading decision model. Experimental results using the proposed stock trading with RSPOP forecast model on real world stock market data are presented. Trading profits in terms of portfolio end values obtained are benchmarked against stock trading with dynamic evolving neural-fuzzy inference system (DENFIS) forecast model, the stock trading without forecast model and the stock trading with ideal forecast model. Experimental results showed that the proposed model identified rules with greater interpretability and yielded significantly higher profits than the stock trading with DENFIS forecast model and the stock trading without forecast model.     

结合深度学习和分解算法的股票价格预测研究

针对股票价格预测问题,实现对非平稳、非线性股票价格序列的预测,提出一种结合深度学习和分解算法的股票价格预测模型.该模型引入自适应噪声的完整集成经验模态分解(CEEMDAN)算法提取股票价格时间序列在时间尺度上的特征,利用注意力机制捕获输入特征参数的权重并结合门控循环单元(GRU)网络进行股票价格预测.实验对苹果、贵州茅...     

Stock-Price Forecasting Based on XGBoost and LSTM

Using time-series data analysis for stock-price forecasting (SPF) is complex and challenging because many factors can influence stock prices (e.g., inflation, seasonality, economic policy, societal behaviors). Such factors can be analyzed over time for SPF. Machine learning and deep learning have been shown to obtain better forecasts of stock prices than traditional approaches. This study, therefore, proposed a method to enhance the performance of an SPF system based on advanced machine learning and deep learning approaches. First, we applied extreme gradient boosting as a feature-selection technique to extract important features from high-dimensional time-series data and remove redundant features. Then, we fed selected features into a deep long short-term memory (LSTM) network to forecast stock prices. The deep LSTM network was used to reflect the temporal nature of the input time series and fully exploit future contextual information. The complex structure enables this network to capture more stochasticity within the stock price. The method does not change when applied to stock data or Forex data. Experimental results based on a Forex dataset covering 2008–2018 showed that our approach outperformed the baseline autoregressive integrated moving average approach with regard to mean absolute error, mean squared error, and root-mean-square error.     

基于PCA和IFOA-BP神经网络的股价预测模型

针对基于BP神经网络的股票价格预测模型在价格预测时存在较大误差的问题,在BP神经网络方法的基础上引入了主成分分析方法(PCA)和改进的果蝇算法(IFOA),提出一种基于PCA-IFOA-BP神经网络的股票价格预测模型。通过PCA对股票历史数据进行降维,减少冗余信息;采用改进的果蝇算法优化BP神经网络的初始权值和阈值;建立基于PCA和IFOA-BP神经网络的股票价格预测模型。对上证指数股票价格数据进行仿真验证,仿真结果表明:在股票价格预测中,该模型比BP神经网络、PCA-BP和PCA-FOA-BP的预测精度更高,是一种有效可行的预测方法。     

Forecasting the volatility of stock price index

Accurate volatility forecasting is the core task in the risk management in which various portfolios’ pricing, hedging, and option strategies are exercised. Prior studies on stock market have primarily focused on estimation of stock price index by using financial time series models and data mining techniques. This paper proposes hybrid models with neural network and time series models for forecasting the volatility of stock price index in two view points: deviation and direction. It demonstrates the utility of the hybrid model for volatility forecasting. This model demonstrates the utility of the neural network forecasting combined with time series analysis for the financial goods.     

基于行为金融学视角的股票市场价格仿真研究

对股票价格走势及其主要影响因素(投资者心理行为)的研究,不仅有助于投资者理解股票市场的运行特点而且还可以给监管当局提供相关的政策建议.文中利用Multi-agents建模技术,对投资者心理行为进行了合理简化,综合考虑了交易制度、宏观经济因素、历史交易信息等因素的影响,构造出了具有自适应能力的投资者(Agent),动态模拟了真实股票市场的运行情况.文章的主要结论为:相对较多的资金投入致使股票价格在较高水平频繁波动;相对过多的投资者也导致股票价格的频繁波动;消极的投资态度引致较低的股票价格水平.文中的仿真方法可以应用到复杂金融衍生品价格形成机制的研究中.     

基于混沌理论进行股票市场的多步预测

提出一种基于混沌理论进行股票价格多步预测 的方法．只需要考虑系统是否混沌,然后依据混沌理论给出了进行股票价格多步预测明确的 最大时间尺度．对于其它复杂非线性系统的多步预测同样具有指导意义．     

A hybrid procedure with feature selection for resolving stock/futures price forecasting problems

Stock/futures price forecasting is an important financial topic for individual investors, stock fund managers, and financial analysts and is currently receiving considerable attention from both researchers and practitioners. However, the inherent characteristics of stock/futures prices, namely, high volatility, complexity, and turbulence, make forecasting a challenging endeavor. In the past, various approaches have been proposed to deal with the problems of stock/futures price forecasting that are difficult to resolve by using only a single soft computing technique. In this study, a hybrid procedure based on a backpropagation (BP) neural network, a feature selection technique, and genetic programming (GP) is proposed to tackle stock/futures price forecasting problems with the use of technical indicators. The feasibility and effectiveness of this procedure are evaluated through a case study on forecasting the closing prices of Taiwan Stock Exchange Capitalization Weighted Stock Index (TAIEX) futures of the spot month. Experimental results show that the proposed forecasting procedure is a feasible and effective tool for improving the performance of stock/futures price forecasting. Furthermore, the most important technical indicators can be determined by applying a feature selection method based on the proposed simulation technique, or solely on the preliminary GP forecast model.     

Adaptive-expectation based multi-attribute FTS model for forecasting TAIEX

In recent years, there have been many time series methods proposed for forecasting enrollments, weather, the economy, population growth, and stock price, etc. However, traditional time series, such as ARIMA, expressed by mathematic equations are unable to be easily understood for stock investors. Besides, fuzzy time series can produce fuzzy rules based on linguistic value, which is more reasonable than mathematic equations for investors. Furthermore, from the literature reviews, two shortcomings are found in fuzzy time series methods: (1) they lack persuasiveness in determining the universe of discourse and the linguistic length of intervals, and (2) only one attribute (closing price) is usually considered in forecasting, not multiple attributes (such as closing price, open price, high price, and low price). Therefore, this paper proposes a multiple attribute fuzzy time series (FTS) method, which incorporates a clustering method and adaptive expectation model, to overcome the shortcomings above. In verification, using actual trading data of the Taiwan Stock Index (TAIEX) as experimental datasets, we evaluate the accuracy of the proposed method and compare the performance with the (Chen, 1996 [7], Yu, 2005 [6], and Cheng, Cheng, & Wang, 2008 [20]) methods. The proposed method is superior to the listing methods based on average error percentage (MAER).     

Mining stock price using fuzzy rough set system

In this study of mining stock price data, we attempt to predict the stronger rules of stock prices. To address this problem, we proposed an effective method, a fuzzy rough set system to predict a stock price at any given time. Our system has two agents: one is a visual display agent that helps stock dealers monitor the current price of a stock and the other is a mining agent that helps stock dealers make decisions about when to buy or sell stocks. To demonstrate that our system is effective, we used it to predict the stronger rules of stock price and achieved at least 93% accuracy after 180 trials.     

A hybrid ANFIS based on n-period moving average model to forecast TAIEX stock

Linear model is a general forecasting model and moving average technical index (MATI) is one of useful forecasting methods to predict the future stock prices in stock markets. Therefore, individual investors, stock fund managers, and financial analysts attempt to predict price fluctuation in stock markets by either linear model or MATI. From literatures, three major drawbacks are found in many existing forecasting models. First, forecasting rules mined from some AI algorithms, such as neural networks, could be very difficult to understand. Second, statistic assumptions about variables are required for time series to generate forecasting models, which are not easily understandable by stock investors. Third, stock market investors usually make short-term decisions based on recent price fluctuations, i.e., the last one or two periods, but most time series models use only the last period of stock price. In order to overcome these drawbacks, this study proposes a hybrid forecasting model using linear model and MATI to predict stock price trends with the following four steps: (1) test the lag period of Taiwan Stock Exchange Capitalization Weighted Stock Index (TAIEX) and calculate the last n-period moving average; (2) use subtractive clustering to partition technical indicator values into linguistic values based on data discretization method objectively; (3) employ fuzzy inference system (FIS) to build linguistic rules from the linguistic technical indicator dataset, and optimize the FIS parameters by adaptive network; and (4) refine the proposed model by adaptive expectation models. The proposed model is then verified by root mean squared error (RMSE), and a ten-year period of TAIEX is selected as experiment datasets. The results show that the proposed model is superior to the other forecasting models, namely Chen's model and Yu's model in terms of RMSE.     

基于后效时间长度的股票价格预测

研究股票价格准确预测问题,针对股票走势预测受政治经济变化等多种因素的影响,具有较强的时变性和非线性特性。传统方法多为线性系统的预测方法,不能有效提高预测精度。为准确确定股票走势后效的时间长度,提高预测精度,根据地统计学与支持向量机提出了一种新的股票价格预测方法。先对数据进行平稳化处理并以地统计学分析股票价格数据的结构性,确定后效时间长度,根据后效时间长度确定各样本的拓阶次数,并对数据进行主成分分析,消除各描述特征携带的噪音。最后采用非线性支持向量机对得到的主成分构建模型并预测。以深发展A股与上证A股两个数据集进行仿真,预测精度均明显高于参比模型。仿真结果表明,新方法能准确预测股价走势,且稳定性好,为股价预测领域提供了有效的手段。     

Processing count queries over event streams at multiple time granularities

Management and analysis of streaming data has become crucial with its applications to web, sensor data, network traffic data, and stock market. Data streams consist of mostly numeric data but what is more interesting are the events derived from the numerical data that need to be monitored. The events obtained from streaming data form event streams. Event streams have similar properties to data streams, i.e., they are seen only once in a fixed order as a continuous stream. Events appearing in the event stream have time stamps associated with them at a certain time granularity, such as second, minute, or hour. One type of frequently asked queries over event streams are count queries, i.e., the frequency of an event occurrence over time. Count queries can be answered over event streams easily, however, users may ask queries over different time granularities as well. For example, a broker may ask how many times a stock increased in the same time frame, where the time frames specified could be an hour, day, or both. Such types of queries are challenging especially in the case of event streams where only a window of an event stream is available at a certain time instead of the whole stream. In this paper, we propose a technique for predicting the frequencies of event occurrences in event streams at multiple time granularities. The proposed approximation method efficiently estimates the count of events with a high accuracy in an event stream at any time granularity by examining the distance distributions of event occurrences. The proposed method has been implemented and tested on different real data sets including daily price changes in two different stock exchange markets. The obtained results show its effectiveness.     

Financial time series forecasting using LPP and SVM optimized by PSO

In this paper, a predicting model is constructed to forecast stock market behavior with the aid of locality preserving projection, particle swarm optimization, and a support vector machine. First, four stock market technique variables are selected as the input feature, and a slide window is used to obtain the input raw data of the model. Second, the locality preserving projection method is utilized to reduce the dimension of the raw data and to extract the intrinsic feature to improve the performance of the predicting model. Finally, a support vector machine optimized using particle swarm optimization is applied to forecast the next day’s price movement. The proposed model is used with the Shanghai stock market index and the Dow Jones index, and experimental results show that the proposed model performs better than other models in the areas of prediction accuracy rate and profit.     

基于ELM和FOA的股票价格预测

针对股票价格预测中应用极限学习机预测存在稳定性不理想的问题,提出了一种改进果蝇优化极限学习机（IFOA-ELM）预测模型的算法。在该算法中,果蝇群通过不断调整群半径来优化ELM的输入层与隐含层连接权值和隐含层阈值,并以优化后的结果为基础,构建ELM预测模型。将IFOA-ELM模型用于股票价格预测。实验表明,与ELM和FOA-ELM相比,IFOA-ELM在股票价格预测中具有更高的预测精度和更好的稳定性。     

融合社交情感分析的股市预测探究

针对现有股市预测研究中所存在的大众情感度量不够全面的问题,提出了一种基于社交情感分析的股市预测模型. 该模型首先基于异构图模型的证券情感量化方法对社交媒介的数据进行情感分析,得到量化的情感时间序列;然后,基于自组织神经网络模型对情感序列及行情指数序列进行建模,从而对股票指数进行预测. 在国内社交媒介及股市行情数据集上的实验结果表明,本文所建立的模型在预测误差和精度上较BP（Back Propagation）神经网络分别提升了15%和12%,能更好地预测股票指数.