Quartic Regression

The quartic regression option finds the equation of the form y = ax4 + bx3 + cx2 + dx + e that best fits a set of data. First, enter the data.

The data shown here are the points {(2,11.4), (3,17), (5,27.3), (7,36.1), (11,47.7), (13,49.9)}.

Press to view the statistics calculation options.

Press for regressions, then to select quartic.

Therefore, the best-fit quartic equation for this data is approximately y = .00011x4 - .0104x3 - .0504x2 + 6.037x - 3.89.
(Note the scientific notation for the first term.)

Note: The resulting quartic equation is an exact fit if five noncollinear, nonparabolic, noncubic data points are entered.

The correlation coefficient r is not calculated.

If an error message occurs, make sure the data was entered correctly or press to view the setup.

Use , , and the menu keys to select List1 for 2Var XList, List2 for 2Var YList, and 1 for 2Var Freq.