Casio SERIES FX-9860G - Manual (Page 296)

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k Quadratic/Cubic/Quartic Regression Graph
A quadratic/cubic/quartic regression graph represents connection of the data points of a
scatter diagram. It uses the method of least squares to draw a curve that passes close to
as many data points as possible. The formula that represents this is quadratic/cubic/quartic
regression.
Ex. Quadratic regression
1(CALC)4(X^2)
6(DRAW)
Quadratic regression
Model formula ....... y = ax 2 + bx + c
a ...............regression second coeffi cient
b ...............regression fi rst coeffi cient
c ...............regression constant term ( y -intercept)
r 2 .............coeffi cient of determination
MSe ........mean square error
Cubic regression
Model formula ....... y = ax 3 + bx 2 + cx + d
a ...............regression third coeffi cient
b ...............regression second coeffi cient
c ...............regression fi rst coeffi cient
d ...............regression constant term ( y -intercept)
r 2 .............coeffi cient of determination
MSe ........mean square error
Quartic regression
Model formula ....... y = ax 4 + bx 3 + cx 2 + dx + e
a ...............regression fourth coeffi cient
b ...............regression third coeffi cient
c ...............regression second coeffi cient
d ...............regression fi rst coeffi cient
e ...............regression constant term ( y -intercept)
r 2 .............coeffi cient of determination
MSe ........mean square error
6-3-7
Calculating and Graphing Paired-Variable Statistical Data