Search results for "stock market"
showing 10 items of 159 documents
Transmisión entre mercados bursátiles y crisis financiera : el caso de España
2020
El trabajo analiza si la interrelación entre el mercado bursátil español y las bolsas de Estados Unidos, Reino Unido, Alemania y Francia se ha visto afectada y cómo por la reciente crisis financiera. Para ello, se estima un modelo VAR- GARCH bivariante, durante el período enero de 2000 a junio de 2012. Del modelo estimado se obtiene una medida del grado de integración de los mercados, el coeficiente de correlación condicional, y de éste se concluye que la crisis subprime produjo un efecto contagio entre los mercados bursátiles. Asimismo, la evidencia empírica permite concluir que en el período poscrisis ha aumentado la interrelación de la bolsa española con la francesa, reduciéndose la inte…
Robust Graph Topology Learning and Application in Stock Market Inference
2019
In many applications, there are multiple interacting entities, generating time series of data over the space. To describe the relation within the set of data, the underlying topology may be used. In many real applications, not only the signal/data of interest is measured in noise, but it is also contaminated with outliers. The proposed method, called RGTL, infers the graph topology from noisy measurements and removes these outliers simultaneously. Here, it is assumed that we have no information about the space graph topology, while we know that graph signal are sampled consecutively in time and thus the graph in time domain is given. The simulation results show that the proposed algorithm h…
Abnormal Stock Market Returns Around Peaks in VIX: The Evidence of Investor Overreaction?
2016
Even though the VIX index was intended to be a measure of future volatility of the stock market, researchers argue that in reality VIX measures the investor sentiment. Anecdotal evidence suggests that peaks in VIX coincide with stock market bottoms followed by rallies, yet so far there have been no scientific evidence confirming this casual observation. In this paper we perform an event study of abnormal stock market returns around peaks in VIX and discuss our findings within the framework of behavioral finance theory. First of all, we detect peaks in VIX using formal turning-point identification procedures and provide detailed descriptive statistics of periods of rising and falling VIX. Th…
GARCH models with changes in variance: An approximation to risk measurements
2003
This study aims to model volatility as an approximation to an optimum measurement of stock market risk because of the importance of this concept for, among other things, the proper management of portfolios. Following the proposal of Lamoureux and Lastrapes (1990), the authors consider that the high degree of persistence detected in GARCH models arises from a poor specification of the equation of the variance due to not considering the possible deterministic changes in the unconditional variance of the financial series. To determine the point in time as well as the duration of these changes, the proposal made by Inclan and Tiao (1994) is used. As an empirical application, whether or not the …
Time Series Momentum in the US Stock Market: Empirical Evidence and Theoretical Implications
2020
There is much controversy in the academic literature on the presence of short-term trends in financial markets and the trend-following strategy's profitability. This paper restricts its attention to the study of time-series momentum (TSMOM) in the US stock market. The paper aims to suggest answers to several important questions regarding TSMOM and to explain the existing controversy. Our answer to the question, whether short-term trends exist, is strongly affirmative. For the first time, we suppose that the returns follow a p-order autoregressive process with p>1 and evaluate this process's parameters. Fairly accurate knowledge of the momentum generating process allows us to provide analyti…
Motives for partial acquisitions between firms in the spanish stock market
2003
The paper analyses the motivations for inter-company investment on the Spanish Stock Market through the study of a sample of significant acquisitions reported to the CNMV (the Spanish Securities and Exchange Commission) by quoted firms. By analysing the sign of the cumulative abnormal returns (CAR) and of the correlations among the gains produced by the operation, an attempt is made to find out which motives predominate of the three most important ones suggested by the literature for takeovers: synergy, agency and hubris. Empirical evidence is presented that in the Spanish Stock Market the main motive for acquiring a holding is similar to synergy, especially in partial acquisitions with pos…
Dominating Clasp of the Financial Sector Revealed by Partial Correlation Analysis of the Stock Market
2010
What are the dominant stocks which drive the correlations present among stocks traded in a stock market? Can a correlation analysis provide an answer to this question? In the past, correlation based networks have been proposed as a tool to uncover the underlying backbone of the market. Correlation based networks represent the stocks and their relationships, which are then investigated using different network theory methodologies. Here we introduce a new concept to tackle the above question--the partial correlation network. Partial correlation is a measure of how the correlation between two variables, e.g., stock returns, is affected by a third variable. By using it we define a proxy of stoc…
Measuring Uncertainty in the Portfolio Selection Problem
2018
In this paper, we propose a new index for ranking portfolios based on the credibility expected return and loss on their investment. We assume that the return on a given portfolio is modeled as a trapezoidal fuzzy variable, whose credibility distribution is built using the data set of its historical returns. The credibilistic loss on the investment for a given portfolio is measured by means of a suitable loss function. In order to take risk-adverse investor attitudes into account, we analyze the performance of some credibility measures related to loss and risk on the investment for a given portfolio and their relationship with similar possibility measures. A numerical example is presented sh…
Econophysics: Scaling and its breakdown in finance
1997
We discuss recent empirical results obtained by analyzing high-frequency data of a stock market index, the Standard and Poor’s 500. We focus on the scaling properties and on its breakdown of the index dynamics. A simple stochastic model, the truncated Levy flight, is illustrated. Successes and limitations of this model are presented. A discussion about similarities and differences between the scaling properties observed in financial markets and in fully developed turbulence is also provided.
Is Big Brother Watching Us? Google, Investor Sentiment and the Stock Market
2013
International audience; This paper proposes a novel measure of French investor sentiment based on the volume of internet search reported by Google Trends. We find that our sentiment indicator correlates well with alternative sentiment measures often used in the literature. Furthermore, we find that investor sentiment influences the behavior of mutual fund investors. The results also reveal evidence about short-run predictability in return. An increase in our sentiment index leads to short-term return reversal. The reversal pattern is more pronounced for smaller firms than larger firms, consistent with the predictions of noise trader's models.