HP (Hewlett-Packard) 50g ユーザーズマニュアル

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Page 18-57
Multiple linear fitting
Consider a data set of the form
Suppose that we search for a data fitting of the form y = b
0
 + b
1
⋅x
1
 + b
2
⋅x
2
 + 
b
3
⋅x
3
 + … + b
n
⋅x
n
.  You can obtain the least-square approximation to the 
values of the coefficients b = [b
0
   b
1
  b
2
  b
3
 … b
n
], by putting together the 
matrix X:
 
_
_
 
_
_
Then, the vector of coefficients is obtained from b = (X
T
X)
-1
X
T
y, where y is 
the vector y = [y
1
y
2
 … y
m
]
T
.
For example, use the following data to obtain the multiple linear fitting
y = b
0
 + b
1
⋅x
1
 + b
2
⋅x
2
 + b
3
⋅x
3,
x
1
x
2
x
3
x
n
y
x
11
x
21
x
31
x
n1
y
1
x
12
x
22
x
32
x
n2
y
2
x
13
x
32
x
33
x
n3
y
3
.
.
.
.
.
.
.
.
.
.
.
x
1,m-1
x
2,m-1
x
3,m-1
n,m-1
y
m-1
x
1,m
x
2,m
x
3,m
n,m
y
m
1
x
11
x
21
x
31
x
n1
1
x
12
x
22
x
32
x
n2
1
x
13
x
32
x
33
x
n3
.
.
.
.
.
.
.
.
.
.
1
x
1,m
x
2,m
x
3,m
n,m