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.
Bull Markets. Quite simply, bull markets refer to an upward trend in the stock market. The length of that uptrend determines whether it is a secular or cyclical bull market. A secular bull market is characterized by above average stock market returns by the S&P 500 for a long time, typically 10 to 20 years.