Red and yellow creates orange. Yellow and blue creates green. The secondary colors can be mixed further to create additional shades. Tertiary colors are the result of a primary and secondary color mixed together. For example, orange mixed with red creates red-orange.
An influential point is an outlier that greatly affects the slope of the regression line. One way to test the influence of an outlier is to compute the regression equation with and without the outlier. This type of analysis is illustrated below.
An outlier is an observation that appears to deviate markedly from other observations in the sample. Identification of potential outliers is important for the following reasons. An outlier may indicate bad data. For example, the data may have been coded incorrectly or an experiment may not have been run correctly. If it can be determined that an outlying point is in fact erroneous, then the outlying value should be deleted from the analysis (or corrected if possible).