Casio FX-9750GII User Manual
Page 153
6-13
I Power Regression Graph
Power regression expresses
y
as a proportion of the power of
x
. The standard power
regression formula is
y
=
a
×
x
b
, so if we take the logarithm of both sides we get In
y
= In
a
+
b
× In
x
. Next, if we say X = In
x
, Y = In
y
, and A = In
a
, the formula corresponds to
linear regression formula Y = A +
b
X.
(CALC)(E)(Pwr)
(DRAW)
The following is the power regression model formula.
y
=
a
·
x
b
a
.............. regression coefficient
b
.............. regression power
I Sinusoidal Regression Graph
Sinusoidal regression is best applied for cyclical data.
The following is the sinusoidal regression model formula.
y
=
a
·sin(
bx
+
c
) +
d
(CALC)(E)(Sin)
(DRAW)
Drawing a sine regression graph causes the angle unit setting of the calculator to automatically
change to Rad (radians). The angle unit does not change when you perform a sine regression
calculation without drawing a graph.
• Certain types of data may take a long time to calculate. This does not indicate malfunction.
I Logistic Regression Graph
Logistic regression is best applied for time-based phenomena in which there is a continual
increase until a saturation point is reached.
The following is the logistic regression model formula.
(CALC)(E)(E)(Lgst)
(DRAW)
• Certain types of data may take a long time to calculate. This does not indicate malfunction.
I Residual Calculation
Actual plot points (
y
-coordinates) and regression model distance can be calculated during
regression calculations.
y =
c
1 + ae
–bx
y =
c
1 + ae
–bx