I use Google News TM to study the relation between news volumes and stock market volatilities. More than nine million stock market-related news stories in English and (Mandarin) Chinese are collected and the dynamics of the news volume and the stock market volatility is compared in both the...

Current models for predicting volatility do not incorporate information flow and are solely based on historical volatilities. We suggest a method to quantify the semantic content of words in news articles about a company and use this as a predictor of its stock volatility. The results show that...

A "compass rose" pattern sometimes appears when stock returns are plotted against themselves with a one-day lag, since stock prices move in discrete steps. In this paper, we perform a Monte Carlo study on simulated stock price series rounded in different ways to mirror the behavior of stocks on...

Nord Pool, the first multinational exchange for electricity trading, has existed since January 1996. Typical characteristics of electricity prices on Nord Pool are a very high volatility and a large number of very large, or extreme, price changes. In this paper we look at hourly spot prices on...

Financial risk management typically deals with low probability events in the tails of asset price distributions. In order to capture the behavior of these tails, one should therefore rely on models that explicitly focus on the tails. Extreme value theory (EVT) based models do exactly that, and...

In a search for more powerful unit root tests, some researchers have recently proposed accounting for the information contained in the GARCH of the innovations. However, while promising, tests with GARCH are difficult to implement, which has made them quite uncommon in the empirical literature....

This paper proposes new unit root tests for panels where the errors may be not only serial and/or cross- orrelated, but also unconditionally heteroskedastic. Despite their generality, the test statistics are shown to be very simple to implement, requiring only minimal corrections and still the...

In search for more efficient unit root tests in the presence of GARCH, some researchers have recently turned their attention to estimation by maximum likelihood. However, although theoretically appealing, the new test is difficult to implement, which has made it quite uncommon in the empirical...