Ekonomernas nya paradigm: Politik in – centralbanker ut

Keynesianism, eller keynesiansk ekonomisk teori, är en makroekonomisk skolbildning inom nationalekonomi som ursprungligen lanserades år 1936 av den brittiske ekonomen John Maynard Keynes. Teorin innehåller bland annat idéer om hur en regering kan dämpa konjunktursvängningar, genom att styra den aggregerade efterfrågan med finanspolitiska verktyg.

Monetarism is a school of thought in monetary economics that emphasizes the role of governments in controlling the amount of money in circulation. Monetarist theory asserts that variations in the money supply have major influences on national output in the short run and on price levels over longer periods. Monetarists assert that the objectives of monetary policy are best met by targeting the growth rate of the money supply rather than by engaging in discretionary monetary policy.Monetarism today is mainly associated with the work of Milton Friedman, who was among the generation of economists to accept Keynesian economics and then criticise Keynes's theory of fighting economic downturns using fiscal policy (government spending). Friedman and Anna Schwartz wrote an influential book, A Monetary History of the United States, 1867–1960, and argued "inflation is always and everywhere a monetary phenomenon". Though he opposed the existence of the Federal Reserve, Friedman advocated, given its existence, a central bank policy aimed at keeping the growth of the money supply at a rate commensurate with the growth in productivity and demand for goods.

Inflation targeting is a monetary policy regime in which a central bank has an explicit target inflation rate for the medium term and announces this inflation target to the public. The assumption is that the best that monetary policy can do to support long-term growth of the economy is to maintain price stability. The central bank uses interest rates, its main short-term monetary instrument.An inflation-targeting central bank will raise or lower interest rates based on above-target or below-target inflation, respectively. The conventional wisdom is that raising interest rates usually cools the economy to rein in inflation; lowering interest rates usually accelerates the economy, thereby boosting inflation. The first three countries to implement fully-fledged inflation targeting were New Zealand, Canada and the United Kingdom in the early 1990s, although Germany had adopted many elements of inflation targeting earlier.

Modern Monetary Theory or Modern Money Theory (MMT) is a heterodox macroeconomic theory that describes currency as a public monopoly for a government and unemployment as the evidence that a currency monopolist is restricting the supply of the financial assets needed to pay taxes and satisfy savings desires. MMT is seen as an evolution of chartalism and is sometimes referred to as neo-chartalism. MMT advocates argue that the government should use fiscal policy to achieve full employment, creating new money to fund government purchases. The primary risk once the economy reaches full employment is inflation, which can be addressed by raising taxes and issuing bonds, to remove excess money from the system. MMT is controversial, with active debate about its policy effectiveness and risks.