20050501
Drawing a Power Regression Graph (
y
=
a
·
x
b
)
Power regression can be used when
y
is proportional to the power of
x
. The normal power
regression formula is
y
=
a
·
x
b
. If we obtain the logarithms of both sides, we get ln(
y
) = ln(
a
)
+
b
· ln(
x
). Next, if we say that X = ln(
x
), Y = ln(
y
), and A = ln(
a
), the formula corresponds to
the linear regression formula Y = A +
b·
X.
u
ClassPad Operation
Start the graphing operation from the Statistics application’s Graph window or List window.
From the Graph window
Tap [Calc] [Power Reg] [OK] [OK]
"
.
From the List window
Tap [SetGraph][Setting...], or
G
.
On the Set StatGraphs dialog box that appears, configure a StatGraph setup with the
setting shown below, and then tap [Set].
Type: PowerR
Tap
y
to draw the graph.
7-5-12
Graphing Paired-Variable Statistical Data
The following is the power regression model formula.
y
=
a
·
x
b
a
:
regression coefficient
b
:
regression power
r
:
correlation coefficient
r
2
:
coefficient of determination
MSe
: mean square error
• MSe
=
Σ
1
n
–
2
i
=1
n
(
ln
(
y
i
)
– (
ln
(
a
)
+
b·
ln
(
x
i
)))
2
Summary of Contents for ClassPad 300 PLUS
Page 11: ...20050501 ClassPad 300 PLUS ClassPad OS Version 2 20 ...
Page 197: ...20050501 2 10 7 Using Verify 4 Input x 2 1 and press E 5 Input x i x i and press E ...
Page 649: ...20050501 u Graph Line Clustered D u Graph Line Stacked F 13 8 2 Graphing ...
Page 650: ...20050501 u Graph Line 100 Stacked G u Graph Column Clustered H 13 8 3 Graphing ...
Page 651: ...20050501 u Graph Column Stacked J u Graph Column 100 Stacked K 13 8 4 Graphing ...
Page 652: ...20050501 u Graph Bar Clustered L u Graph Bar Stacked 13 8 5 Graphing ...
