How machine learning is transforming the stock exchange

The public perception of stock exchanges remains little changed since the Big Bang deregulated the financial markets. Anytime a trading floor is depicted in a film or TV series, you can expect to see a group of men frantically waving their arms and shouting at a bank of screens showing the ups and downs of share prices. But the reality is different. Around three-quarters of exchanges on the NYSE and Nasdaq are now carried out by algorithms - computer programs designed to follow a particular set of rules - and not human traders. The last stock exchange in Scotland closed in 1973.