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.
This is especially relevant to participants in bull markets since bulls are herding animals. A bull market is also described as a bull run. The United States has been described as being in a long-term bull market since about 1983, with brief upsets including the Panic of 1987 and the NASDAQ crash of 2000-2002.