This paper studies the reaction of share prices in the Chilean securities market at the sectoral level to the arrival of COVID-19 in the country. The following question is answered: Did the Chilean market act efficiently before the arrival of COVID-19? To answer this question, an event study...

This paper aims to discuss market efficiency due to the changes that appeared in this field after the COVID-19 outburst. The OMX exchange and its indices are taken into consideration because they represent markets not analysed in such a context before (a) Baltic: Estonia, Latvia and Lithuania;...

This paper analyzes market efficiency (EMH) with the day-of-the-week effect and the changes that might appear after the outbreak of the COVID-19 pandemic, based on the example of the OMX Exchange and its indices. Before the pandemic, only the OMX Baltic All‑share index was efficient; during...