least-squares-method[1].pdf

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  • _______________________________________

    3 4 5 6 7 8 9

    1214

    1618

    20

    x

    y

  • 2

    2 (Independent variable) (Dependent variable)

    1.

    Y = a+bX Y X a Y b Y

    2. (Scatter Diagram) 2

    X Y X Y

    X Y Y Y

    X X

    1 2 1 2 X Y

  • 3

    Y Y

    X X 3 4

    3 4 X Y

    Y Y

    X X

    5 6

    5 6 X Y

    Y

    X 7

    7 X Y

  • 4

    3. (Least Squares Method) a b a b

    Y = a+bX (Least squares method)

    (Normal

    equations) n n

    i ii=1 i=1

    n n n2

    i i i ii=1 i=1 i=1

    y = an+b x (1)

    x y = a x +b x (2)

    i i =

    1,2,3,,n a, b i i(x ,y )

  • 5

    6

    (X) 1 2 3 2 1 3 (Y) () 4 7 10 8 3 10

    . . . 4

    .

    1.0 1.5 2.0 2.5 3.0

    34

    56

    78

    910

    x

    y

    ***************************

    . Y = a+bX

    n n

    i ii=1 i=1

    n n n2

    i i i ii=1 i=1 i=1

    y = an+b x (1)

    x y = a x +b x (2)

    (1) (2)

  • 6

    8

    ii 1

    x 12=

    = 8

    ii 1

    y 42=

    = 8

    i ii 1

    x y 97=

    = 8

    2i

    i 1x 2

    =8=

    42 = 6a+12b (1)97 = 12a+28b (2)

    a = 0.50 b = 3.25

    Y=0.50+3.25X

    *************************

    . 4 (x=4)

    Y=0 .50+3.25(4) = 13.5 () = 1,350

    *************************

  • 7

    2541- 2551

    1 1. x y

    x -3 -1 0 1 3 y 0 a a+3 a+4 a+6

    a x y 1.55 x = 4 y 1. 8.7 2. 10.8 3. 11.2 4. 12.8

    2. y = mx + c (y) (x) 5

    28 = 5c + 10m .......(1) 67 = 10c + 30m .......(2)

    . x = 5 y = 8.9 . x = 5.6 1.

    2. 3. 4.

    3. ( x) GPA ( y) 0.02 Y 2.7

  • 8

    . 10 0.2

    . 3 15

    1. 2. 3. 4.

    4. (y) () (x) () 130 2545

    y = 8-0.5x 1-4 2545 4, 2, 8, 10

    1. 2.5 2. 10 3. 17.5 4. 22.5 5. (y) ()

    (x) () 8

    8

    ii 1

    x 4=

    = 8 1 8

    ii 1

    y 4=

    = 8

    i ii 1

    x y 286=

    =8

    2i

    i 1x 34

    == 8

    . 6 51,250

    . 1 11,250

    1. 2.

  • 9

    3. 4.

    ****************************************************************** 2 1. (x) (y)

    y = 200 + 0.85x 1,000

    2.

    ( y) ( x) y = a + 0.75x x = 40 y = 60 x = 60

    3. () (y) ..2538-2545 x .. 2538 2539 2540 2541 2542 2543 2544 2545

    x -7 -5 -3 -1 1 3 5 7 ( 2 ) y = 0.54x + 38.85 ..2547

    4. ..2537 ..2546 (y) () (x) ..2541 2542 x = -1 1

    y = 192 + cx

  • 10

    .. 2547 316.3 .. 2548

    5. x y

    8

    ii 1

    x 3=

    = 2 8

    ii 1

    y 16=

    =8

    i ii 1

    x y 65=

    = 8

    2i

    i 1x 140

    ==

    82i

    i 1y 3

    == 4

    x = 8 y ()

    . (2552). ADMISSIONS52 . : .

    . (2551). .4-5-6. :

    .

    2 X Y X Y X Y Y Y Y