The new Keynesians made more rapid progress in understanding the microeconomics of unemployment than in understanding the microeconomics of nominal price rigidity. But the past five years have seen important breakthroughs in this second area. This paper will describe these breakthroughs, discuss...

Lectures and other class meetings are a primary means of instruction in almost all undergraduate courses. Yet almost everyone who has taught an undergraduate course has probably noticed that attendance at these meetings is far from perfect. There is surprisingly little systematic evidence,...