Casio fx-9860G SD - Manual (Page 293)

20050401
k k k k 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 coefficient
b ............. regression first coefficient
c ............. regression constant term ( y -intercept)
r 2 ............ coefficient of determination
MSe ........ mean square error
Cubic regression
Model formula ..... y = ax 3 + bx 2 + cx + d
a ............. regression third coefficient
b ............. regression second coefficient
c ............. regression first coefficient
d ............. regression constant term ( y -intercept)
r 2 ............ coefficient of determination
MSe ........ mean square error
Quartic regression
Model formula ..... y = ax 4 + bx 3 + cx 2 + dx + e
a ............. regression fourth coefficient
b ............. regression third coefficient
c ............. regression second coefficient
d ............. regression first coefficient
e ............. regression constant term ( y -intercept)
r 2 ............ coefficient of determination
MSe ........ mean square error
6-3-7
Calculating and Graphing Paired-Variable Statistical Data