User`s guide

– 29 –
Sample Covariance = 35 E A U r 3 ,
A U 3 - A X 1 -
A X r 1 F \
E A U 3 , 1 F =
uLogarithmic, Exponential, Power, and Inverse
Regression
• Use the same key operations as linear regression to
recall results for these types of regression.
• The following shows the regression formulas for each
type of regression.
uQuadratic Regression
• The regression formula for quadratic regression is:
y = A + Bx + Cx
2
.
• Example:
Perform quadratic regression to de-
termine the regression formula terms
for the data nearby. Next, use the re-
gression 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
P1.6 S 50 P 23.5 S
74 P38.0 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 =
x
i
y
i
29 1.6
50 23.5
74 38.0
103 46.4
118 48.0
Logarithmic Regression y  A  B ⴢ In x
Exponential Regression y  A ⴢ e
B
·
x
(In y  In A + Bx)
Power Regression y  A ⴢ x
B
(In y  In A + BIn x)
Inverse Regression y  A  B
ⴢ
1
/x