LEXIBOOK GC1000i, Инструкция по эксплуатации, Страница: 36 / 75

2.5.6 Power regression
●
The regression formula is y=A.x
B
(lny=lnA+Blnx). Enter both data x and y as logarithms (ln).
●
Estimated values x, and y based on the regression formula can be calculated using the following for-
mulas:
y = A e
Bx
x =
●
Correction is performed the same as in linear regression. Constant term A is obtained
by
, estimated value y is obtained by x
, and estimated value x is obtained by y
.
Σ
x
2
Σ
y,
Σ
y
2
and Sxy are obtained by
Σ
lnx,
Σ
(lnx)
2
,
Σ
lny,
Σ
(lny)
2
and Slnx.lny
respectively.
Example
xi yi
6.9 21.4
12.9 15.7
19.8 12.1
26.7 8.5
35.1 5.2
The data in the above can be
used to obtain the terms of
the regression formula and
the correlation coefficient.
Based on the regression
formula, estimated value y
can be obtained for xi=16,
and estimated value x can be
obtained for yi=20.
2.5.5 Exponential regression
●
The regression formula is y=A e
B.x
(lny=lnA+Bx). Enter the y date as the logarithm of y(ln), and the
x data the same as that for linear regression.
●
Estimated values x, and y based on the regression formula can be calculated using the following for-
mulas
y = A e
Bx
x =
●
Correction is performed the same as in linear regression. Constant term A is obtained
by
, estimated value y is obtained by x
, and estimated value x is obtained by y .
Σ
y,
Σ
y
2
and
Σ
xy are obtained by
Σ
lny,
Σ
(lny)
2
and Sx.lny respectively.
- 36 -
Copyright L
EXIBOOK
2002
GB
^ ^
^ ^
^ ^
^
Iny - InA
B
EXE
y
^
EXE
SHIFT
Ans
e
x
EXE A SHIFT SHIFT
e x SHIFT in
EXE
SHIFT x
Key Operation
6.9 21.4
12.9
15.7
19.8 12.1
26.7 8.5
35.1 5.2
16
20
^
^
In
÷
MODE
Display
6.9
12.9
19.8
26.7
35.1
30.15716545
-0.048870452
-0.997192153
13.79760894
8.403652083
Remark
Clear memory
Constant term A
Regression coefficient B
Correlation coefficient r
y when xi=16
x when yi=20
EXE SHIFT Scl
EXE
EXE
SHIFT B
EXE R SHIFT
DT
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In
DT SHIFT
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EXE SHIFT In
In
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