Measuring the 'Halloween effect' – can retail investor optimism really affect stock returns?
- Written by Moritz Wagner, Lecturer, University of Canterbury

The upcoming spooky season is not only a favourite time for most kids (and a few adults), but also for share markets due to what’s been called the “Halloween effect” – often referred to as “sell in May and go away”.
There is hardly a year investors and the media do not refer to the popular market...