Patrick Harker, Federal Reserve Bank of Philadelphia President, says there are some risks to keeping rates too low for too long. Troy Gayeski, Skybridge Capital Co-CIO, says it might be a year where success or failure is determined by whether or not you had a meaningful position in bitcoin. Beata Kirr, AB Co-Head of Investment Strategies, says it's a mistake to be a U.S.-only investor. Robert Tipp, PGIM Chief Investment Strategist & Head of Global Bonds, explains why the belly of the yield curve is under pressure.