METODE LEAST SQUARE (1)

METODE LEAST SQUARE

TAHUN ( n ) PENJUALAN ( y )

X XY X²

1996 17500 -9 -157500 81

1997 21500 -7 -150500 49

1998 24000 -5 -120000 25

1999 _{27500 -3 -82500 9}

2000 30000 -1 -30000 1

2001 32000 1 32000 1

2002 35000 3 105000 9

2003 37500 5 187500 25

2004 39000 7 273000 49

2005 41200 9 370800 81

305200 Σ=0 427800 330

LEAST SQUARE

Yt = a + bx ----> a : konstanta bx : Variabel x

a = Σy = 305.200 = 30.500 n 10

b = Σxy = 427.800 =1296,36

Σx² 330

Jadi,,

Y06 = a + bx

= 30.520 + 1296,36 ( 11 ) = 44.779,96

SEMI AVERAGE

TAHUN PENJUALAN

X

SEMI

TOTAL

SEMI AVERAGE

1996 17500 0

1997 21500 1

1998 24000 2

----> ₁₂₀₅₀₀

120500 = 24100 (Y1) 5

1999 27500 3

2000 30000 4

2001 32000 5

2002 35000 6

---> ₁₈₄₇₀₀

184700 = 36940 ( Y

2) 5

2003 37500 7

2004 39000 8

2005 41200 9

Y1 = a + bx1

Y2 = a + bx2

JADI,,

24.100 = a + 2b 36.940 = a + 7b b = 2568 a = 18964

Y06 = a + bx