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
Given So calculate AB. Solution The new matrix will contain size 2 x 4. The entry in row 1 and column 1 of the new matrix will be determined by multiplying row 1 of


1. Find the slope and the y-intercept of the line whose equation is 5x + 6y = 7. 2. Find the equation of the line that is parallel to 2x + 5y = 7 and passes through the mid poin

Give an example of each of the following given below . You do not require to give any justi cation. (a) A nonempty, bounded subset of Q with no in mum in Q. (b) A subspace of

Differentiate following functions.                   g ( x ) = 3sec ( x ) -10 cot ( x ) Solution : There actually isn't a whole lot to this problem.  We'll just differentia

In the earlier section we introduced the Wronskian to assist us find out whether two solutions were a fundamental set of solutions. Under this section we will look at the other app

What is Angles? An angle is made up of two rays with a common endpoint, which is called the vertex. The sides of the angle are rays. An angle is denoted by "θ". When two li

Leslie ordered a slice of pizza for $1.95, a salad for $2.25, and a soda for $1.05. What was the total cost of her order? The cost of every item must be added together; $1.95 +

Before proceeding along with in fact solving systems of differential equations there's one topic which we require to take a look at. It is a topic that's not at all times taught in

calcula el área de la región sombreada de un rectángulo cuya base es 12.6 cm y su altura es 8.4