Asia stocks remain cautious ahead of Yellen speech

Asia stocks tilted slightly upwards Friday but remained cautious ahead of a speech from the US central bank head and after a weak lead from Wall Street as oil pulled back below $50 a barrel. Comments from the Group of Seven leaders Friday morning stressed the importance of global economic growth while stating the potentially disastrous economic consequences of Britain's exit from the EU. Traders are sitting tight for clues about the prospects of an imminent US rate hike as Federal Reserve chair