Hillary Clinton and Donald Trump have been pitching at voters their plans to revitalise the American economy. The proposals from Mr Trump, the Republican nominee, come with the usual dose of cognitive dissonance; he claims to be a fan of fiscal stimulus yet his new economic advisory committee consists of what seem to be the last surviving “supply-siders”, proponents of Reagan-era trickle down theory

. Mrs Clinton’s plans have more intellectual coherence — the Democratic nominee is promising big investments in infrastructure, manufacturing and clean energy, intended to create better paying jobs. But neither candidate has fully addressed the most important trend in labour markets — the gig economy.

A spate of research by everyone from high-profile academics to