Forecasting by using least squares, Mathematics

Forecasting By Using Least Squares

Data have been kept of sales over the last seven years

Year

1

2

3

4

5

6

7

Sales (in '000 units

14

17

15

23

18

22

27

It is required to forecast the sales for the 8th year

Solution

Years (x)

Sales (y)

xy

x2

1

14

14

1

2

17

34

4

3

15

45

9

4

23

92

16

5

18

90

25

6

22

132

36

7

27

189

49

       Σx=28

     Σy = 136

       Σxy=596

    Σx2= 140

136 = 7a + 28b

596 = 28a + 140b

∴b = 1.86

And substituting in one of the equations we acquire

a = 12

∴ Regression line = y = 12 + 1.86x

Or, Sales in ('000s of units) = 12.00 + 1.86 (no of years)

We utilize this expression for forecasting, for 8th year sales = 12 + 1.86 (8)

=26.88 that is 26,888 units.

Posted Date: 2/16/2013 7:49:36 AM | Location : United States







Related Discussions:- Forecasting by using least squares, Assignment Help, Ask Question on Forecasting by using least squares, Get Answer, Expert's Help, Forecasting by using least squares Discussions

Write discussion on Forecasting by using least squares
Your posts are moderated
Related Questions
how solve the inverse matrices using the matlab?

Consider the finite state machine whose state transition table is : Draw the graph for it.  Ans: The graph for the automata according to the transition table is drawn b

5645.356 turn into fraction

how to do fraction?

Patrick has a rectangular patio whose length is 5 m less than the diagonal and a width which is 7 m less than the diagonal. If the field of his patio is 195 m 2 , what is the lengt

Stuckeyburg is a very small town in rural America. Use the map to approximate the area of the town. a. 40 miles 2 b. 104 miles 2 c. 93.5 miles 2 d. 92 miles 2

sin^2alpha *sec^2beta +tan^2 beta *cos^2alpha=sin^2alpha+tan^2 beta

If the hight of pipe is 18 inches, what is the volume of the shaded region in terms of π? a. 31.5π in 3 b. 126π in 3 c. 157.5 in 3 d. 58.5 in 3


to difine trigonometric ratios of an angle,is it necessary that the initial ray of the angle must be positive x-axis?