How is a residual calculated in regression analysis? By adding the observed value and the predicted value. By multiplying the observed value by the predicted value. By dividing the observed value by the predicted value. By subtracting the predicted value from the observed value. In the numerical method for detecting outliers, a data point is considered an outlier if its residual is: Exactly equal to the standard deviation of the residuals. Less than the mean of the residuals. More than twice the standard deviation of the residuals. The smallest residual in the dataset. What does the standard deviation of the residuals (s) represent in regression analysis? The total number of data points in the dataset. The variability of the residuals around the regression line. The spread of the observed data points. The average of the predicted values.