The effects of a change in market abuse regulation on abnormal returns and volumes: Evidence from the Amsterdam stock market

The Market Abuse Directive came into effect on 1 October 2005. One of its purposes is to reduce illegal insider trading and leakage of information prior to official releases by increasing penalties. This paper investigates the effects of the Market Abuse Directive through an event study approach. Using�a dataset of almost 5,000 corporate news announcements, the analysis reveals that the information value of announcements, measured by the announcement day abnormal return and abnormal volume, is not significantly different after the new regulation than it was before although the number of releases has increased significantly. Trading suspicious of illegal insider trading and leakage of information, measured in terms of cumulative average abnormal returns and volumes for the 30 days prior to the news announcement, has significantly declined for small capitalization firms, for announcements containing information about alliances and mergers and acquisitions and for firms in the technology sector.

Do returns and volatility spillovers exist across tech stocks, cryptocurrencies and NFTs?

This study examines the connectedness between technology stocks, cryptocurrencies, and non-fungible tokens (NFTs) using daily returns and risk data. We found that while there is strong connectedness within asset classes, connectedness between different types of assets is weak. Structural breaks in the VAR system did not change the degree of connectedness. Our findings suggest that interconnectivity between these assets is not significant enough to indicate a high level of correlation. This research provides valuable insights into the interplay between these markets and suggests diversifying portfolios to mitigate risks associated with these assets

The value effects of changes in leverage: Evidence from the Travel and Leisure sector

It is well documented that the Travel and Leisure sector is capital intensive when compared to other sectors due to the high level of capital required for fixed assets. Given this, this paper examines the relation between changes in leverage and stock returns of firms in this sector, in addition to examining whether changes in leverage have any significant effect on a sector basis. Using a final sample of 173 firms over the period between 1993 and 2012, we find that leverage only acts as a significant determinant of returns in the case of highly levered firms, as would be the case in the Travel and Leisure sector

Coherent control of injection currents in high-quality films of Bi2Se3

Films of the topological insulator Bi2Se3 are grown by molecular beam epitaxy with in-situ reflection high-energy electron diffraction. The films are shown to be high-quality by X-ray reflectivity and diffraction and atomic-force microscopy. Quantum interference control of photocurrents is observed by excitation with harmonically related pulses and detected by terahertz radiation. The injection current obeys the expected excitation irradiance dependence, showing linear dependence on the fundamental pulse irradiance and square-root irradiance dependence of the frequency-doubled optical pulses. The injection current also follows a sinusoidal relative-phase dependence between the two excitation pulses. These results confirm the third-order nonlinear optical origins of the coherently controlled injection current. Experiments are compared to a tight-binding band structure to illustrate the possible optical transitions that occur in creating the injection current.Comment: 11 pages, 3 figure, journal articl