The stock market is like a small row boat on a rough sea, bouncing around as it drifts, whereas the macro economy is like a large ocean liner, very ponderous and difficult to maneuver but without such a rough journey.
A potentially useful property of forecasts based on cointegration is that when extended some way ahead, the forecasts of the two series will form a constant ratio, as is expected by some asymptotic economic theory.
Forecasts vary in horizon, from a few seconds up to a few days in financial markets, compared to from one to several months for macro variables. We have to provide uncertainty intervals around the central forecasts to indicate the extent to which we are unclear about the future.
I was born in Swansea in the Principality of Wales in September 1934 and named Clive William John Granger. The 'William John' names were traditional Granger boy's names, and my mother liked the name Clive because some popular musician at the time had it.
I work with the macro economy, which involves the major variables that measure the health of the whole economy, such as total consumption, investment, income, employment, and inflation.
In 1973, I was offered a professorship at the University of California, San Diego. Although I was certainly not unhappy at Nottingham, I had been there over twenty years from starting undergraduate studies to Professor of Applied Statistics and Econometrics, and I thought that a change of scene was worth considering.
On completing my degree, I started a Ph.D. in statistics, although I knew very little about the topic. My supervisor was Professor Harry Pitt, who was an excellent pure mathematician and probabilist.
