E-31
xi
yi
29
1.6
50
23.5
74
38.0
103
46.4
118
48.0
u
Quadratic Regression
• The regression formula for quadratic regression is:
y
= A + B
x
+ C
x
2
.
•
Example:
Perform quadratic regression to determine the regression
formula terms for the data nearby. Next, use the
regression formula to estimate the values for
n
(estimated value of
y
) for
xi
= 16 and
m
(estimated value
of
x
) for
yi
= 20.
In the REG Mode:
r
3
(Quad)
A
B
1
(Scl)
<
(Stat clear)
29
P
1.6
S
50
P
23.5
S
74
P
38.0
S
103
P
46.4
S
118
P
48.0
S
Regression Coefficient A =
–35.59856934
A
X
r
r
1
<
Regression Coefficient B =
1.495939413
A
X
r
r
2
<
Regression Coefficient C =
– 6.71629667
×
10
–3
A
X
r
r
3
<
n
when
xi
is 16 =
–13.38291067
16
A
X
r
r
r
3
<
m
1
when
yi
is 20 =
47.14556728
20
A
X
r
r
r
1
<
m
2
when
yi
is 20 =
175.5872105
20
A
X
r
r
r
2
<
• After inputting data, you can perform the key operations that calcutate
statistical results (regression coefficients,
n
,
m
1
, etc.) in any order. You do
not need to follow the order shown above.
Data Input Precautions
• To input the same data twice: <
x
-data>
P
<
y
-data>
S
S
• To input multiple entries of the same data by specifying the “frequency”:
<
x
-data>
P
<
y
-data>
A
G
<frequency>
S
Example:
To input the data X = 20, Y = 30 five times
20
P
30
A
G
5
S
• Precautions when editing data input for standard deviation also apply for
regression calculations.
