The Halloween effect predicts that stock markets in the winter months (November through April) generate significantly higher returns than in the summer months (May through October). This paper examines the time-varying behavior of the Halloween effect within a new historical dataset that covers...

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...

The ancient Chinese Almanac lists days that are (in)auspicious for certain actions or events. We find that the initial returns for Initial Public Offerings (IPO), an essential corporate event, are significantly lower on days listed by the Almanac as unlucky. The effect of calendar superstition...

This study identifies day-of-the-week effects in business surveys using monthly data from the ifo Institute. The odds are higher that companies are more likely to exhibit more pessimistic business expectations for the upcoming months on Mondays and more optimistic expectations at the end of the...