N . σ x, N . σ, Ln y – ln – Casio fx-50F PLUS User Manual
Page 49

E-48
Logarithmic Regression
Command
Calculation Formula
Regression Formula
Constant Term a
a
=
n
Σy
i
–
b.
Σ
ln
x
i
Regression Coeffi cient b
b =
n.
Σ
(ln
x
i
)
2
–
(
Σ
ln
x
i
)
2
n.
Σ
(ln
x
i
)
y
i
–
Σ
ln
x
i
.Σy
i
Correlation Coeffi cient r
r
=
{
n.
Σ
(ln
x
i
)
2
–
(
Σ
ln
x
i
)
2
}{
n.
Σy
i
2
–
(
Σy
i
)
2
}
n.
Σ
(ln
x
i
)
y
i
–
Σ
ln
x
i
.Σy
i
Estimated Value
m
m = e
y
– a
b
Estimated Value
n
n =
a
+
b
lnx
e
Exponential Regression
Command
Calculation Formula
Regression Formula
Constant Term a
a
= exp
(
)
n
Σ
ln
y
i
–
b
.Σx
i
Regression Coeffi cient b
b =
n.
Σx
i
2
–
(
Σx
i
)
2
n.
Σx
i
ln
y
i
–
Σx
i
.Σ
ln
y
i
Correlation Coeffi cient r
r
=
{
n.
Σx
i
2
–
(
Σx
i
)
2
}{
n.
Σ
(ln
y
i
)
2
–
(
Σ
ln
y
i
)
2
}
n.
Σx
i
ln
y
i
–
Σx
i
.Σ
ln
y
i
Estimated Value
m
m
=
b
lny – ln
a
Estimated Value
n
n
=
a
e
b
x
ab
Exponential Regression
Command
Calculation Formula
Regression Formula
Constant Term a
a
= exp
(
)
n
Σ
ln
y
i
–
ln
b
.Σx
i
Regression Coeffi cient b
b = exp
(
)
n.
Σx
i
2
–
(
Σx
i
)
2
n.
Σx
i
ln
y
i
–
Σx
i
.Σ
ln
y
i
Correlation Coeffi cient r
r
=
{
n.
Σx
i
2
–
(
Σx
i
)
2
}{
n.
Σ
(ln
y
i
)
2
–
(
Σ
ln
y
i
)
2
}
n.
Σx
i
ln
y
i
–
Σx
i
.Σ
ln
y
i