Global outllookWorld shares slid towards their fourth weekly loss in the last five on Friday, as a boost from a supportive-sounding European Central Bank gave way to caution ahead of closely watched U.S. jobs data. Rumbling concerns about China had consigned Asian shares to a seventh straight weekly loss and Europe's markets started 1.3 to 1.6 percent in the red after gains of almost 2.5 percent on Thursday. Those had been driven by ECB President Mario Draghi, who said the bank was prepared to expand its 1 trillion euro stimulus program aimed at lifting growth and inflation in the euro zone. But Friday's focus was on whether U.S. jobs data due at 1230 GMT would keep Federal Reserve on track to raise its record low interest rates.