A Regression Coeffi cient and Estimated Value Calculation
Formula Table
The following table shows the calculation formulas used by the regression coeffi cient and
estimated value commands for each regression calculation type.
Linear Regression
Command
Regression Formula
Constant Term a
Regression Coeffi cient b
Correlation Coeffi cient r
Estimated Value
Estimated Value
Quadratic Regression
Command
Regression Formula
Constant Term a
Regression Coeffi cient b
Regression Coeffi cient c
However,
Sxx
Sxx
Sxy
Sxy
Command
Estimated Value
Estimated Value
Estimated Value
a =
b
r
a =
b =
c =
Σx
Σx
2
2
(
(
)
)
Σx
Σx
i
i
2
2
=
=
–
–
i
i
n
n
. Σy
. Σy
Σx
Σx
(
(
Σx
Σx
i
i
i
i
y
y
=
=
–
–
i
i
i
i
n
n
1
1
2
2
Calculation Formula
Σy
– b . Σx
i
i
n
n . Σx
– Σx
. Σy
y
i
i
i
=
n . Σx
Σx
2
2
–
(
)
i
i
n . Σx
y
i
i
=
n . Σx
Σx
2
–
(
)
{
i
i
y – a
=
b
=
+
x
a
b
Calculation Formula
Σy
Σx
( )
i
i
– b
– c
n
n
xy .
2
2
2
x
x
x
S
S
– S
xx .
2
2
x
x
S
S
– (S
y .
2
x
xx
S
S
– S
xx .
2
2
x
x
S
S
– (S
Σx
Σx
2
2
3
3
Sxx
Sxx
=
=
i
i
Σx
Σx
2
2
2
2
Sx
Sx
x
x
=
=
i
i
)
)
Σx
Σx
2
2
2
2
Sx
Sx
y
y
=
=
i
i
Calculation Formula
2
– b + b
– 4c
=
2c
– b – b
2
– 4c
=
2c
= a + bx + cx
2
E-47
i
. Σy
– Σx
i
i
n . Σy
Σy
2
2
–
2
(
)
}{
}
i
i
Σx
2
( )
i
n
y .
2
xx
S
2
2
xx
)
xy .
2
xx
S
2
2
xx
)
Σx
Σx
Σx
Σx
.
.
2
2
(
(
)
)
i
i
i
i
–
–
n
n
Σx
Σx
2
2
2
2
(
(
)
)
i
i
4
4
–
–
n
n
. Σy
. Σy
Σx
Σx
2
2
(
(
)
)
i
i
i
i
y
y
–
–
i
i
n
n
a – y
(
)
a – y
(
)