Casio CFX-9850G PLUS, User'S Manual & Technical Reference

Page: 291 / 486

263
Calculating and Graphing Paired-Variable Statistical Data
18 - 4
k k k k k
Logarithmic Regression Graph
P.254 Logarithmic regression expresses
y
as a logarithmic function of
x
. The standard
logarithmic regression formula is
y
=
a
+
b ×
In
x
, so if we say that X = In
x
, the
formula corresponds to linear regression formula
y
=
a
+
b
X.
6
(
g
)
1
(Log)
1 2 3 4 5
6
6
(DRAW)
a ......
regression constant term
b ......
regression coefficient
r ......
correlation coefficient
r
2
..... coefficient of determination
k k k k k
Exponential Regression Graph
P.254 Exponential regression expresses
y
as a proportion of the exponential function of
x
. The standard exponential regression formula is
y
=
a
×
e
bx , so if we take the
logarithms of both sides we get In
y
= In
a
+
bx
. Next, if we say Y = In
y
, and A = In
a
,
the formula corresponds to linear regression formula Y = A +
bx
.
6
(
g
)
2
(Exp)
1 2 3 4 5
6
6
(DRAW)
a ......
regression coefficient
b ......
regression constant term
r ......
correlation coefficient
r
2
..... coefficient of determination