BUS101: Introduction to Business

In recent years, economic theory has moved towards the study of economic fluctuation rather than the study of business cycles. However, some economists use the phrase "business cycle" as a convenient shorthand.

For Milton Friedman, the term "business cycle" is a misnomer because of its non-cyclical nature. Friedman believed that for the most part, excluding very large supply shocks, business declines are more of a monetary phenomenon.

Rational expectations theory leads to the efficient-market hypothesis, which states that no deterministic cycle can persist because it would consistently create arbitrage opportunities.

Much economic theory also holds that the economy is usually at or close to equilibrium. These views have led to the formulation of the idea that observed economic fluctuations can be modeled as shocks to a system.

In the tradition of Slutsky, business cycles can be viewed as the result of stochastic shocks that on the aggregate form a moving average series. However, recent research employing spectral analysis has confirmed the presence of business (Juglar) cycles in the world GDP dynamics at an acceptable level of statistical significance.

Long Term Growth
Deviations from the long term growth trend US 1954–2005