The document discusses several concepts from New Classical economics including:
1) How an underprediction of inflation could cause an increase in employment if it leads to a higher real wage.
2) How a rise in aggregate demand could cause a rise in national output if expectations are wrong and the short-run aggregate supply curve shifts out.
3) How a rise in aggregate demand could cause a fall in national output if expectations are correct and the long-run aggregate supply curve is vertical.
4) How the short-run Phillips curve varies depending on whether inflation expectations are lower than, equal to, or higher than actual inflation.