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 terms bear and bull are used to describe general actions and attitudes, or sentiment, either of an individual or the market. A bear market refers to a decline in prices, usually for a few months, in a single security or asset, group of securities or the securities market as a whole. A bull market is when prices are rising. The actual origins of these expressions are unclear.