Lead–lag effect

A lead–lag effect, especially in economics, describes the situation where one (leading) variable is cross-correlated with the values of another (lagging) variable at later times.{{Citation needed|date=January 2022}}

In nature and climate, bigger systems often display more pronounced lag effects. The Arctic Sea Ice minimum is on September 17, three months after the peak in daylight (sunshine) hours in the northern hemisphere, according to NASA.NASA, "2014 Arctic Sea Ice Minimum Sixth Lowest on Record," http://www.nasa.gov/press/2014/september/2014-arctic-sea-ice-minimum-sixth-lowest-on-record/

For example, economists have found that in some circumstances there is a lead-lag effect between large-capitalization and small-capitalization stock-portfolio prices.Andrew W. Lo and A. Craig MacKinlay, "When are contrarian profits due to stock market overreaction," Review of Financial Studies 3 (2), 175-205 (1990).

(A loosely related concept is that of lead-lag compensators in control theory, but this is not generally referred to specifically as a "lead-lag effect."){{Citation needed|date=January 2022}}