The Fed is focusing on 'flawed' data and keeping rates high will result in a big policy mistake, economist says

• The Fed's reliance on "flawed" inflation data to keep interest rates high will spur a policy mistake, David Rosenberg says.
• The latest PCE and GDP data may be misrepresenting the actual state of the economy.
• The Fed has been too optimistic about jobs data that's based on nonfarm payrolls, Rosenberg said. 

The Federal Reserve's fixation on a streak of "flawed" data to justify keeping interest rates higher for longer is bound to spark a policy mistake, according to top economist David Rosenberg.