I. When the sum of the residuals is greater than zero, the data set is nonlinear. II. A random pattern of residuals supports a linear model. III. A random pattern of residuals supports a non-linear model.
bull market definition. A market, especially a stock market, characterized by rising prices; the opposite of a bear market. We can always go back to worrying; we are still in a bull market for fear.
The average age of a bull market, meanwhile, is 57 months. So, if you assume that every bull-market year is equivalent to about 16.6 human years (948 months divided by 57 months), this eight-year-old bull market is actually 133 years old. (The oldest person on Earth is currently 117.)