Forecasting by using least squares, Mathematics

Assignment Help:

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.


Related Discussions:- Forecasting by using least squares

Find the equation of circle concentric – coordinate geometry, 1. A point P(...

1. A point P(a,b) becomes (3,c) after reflection in x - axis, and (d,6) after reflection in the origin. Show that a = 3, b = - 6, c = 6, d = 2 2. If the pair of lines ax² + 2pxy

Find out height of the box which will give maximum volume, We contain a pie...

We contain a piece of cardboard i.e. 14 inches by 10 inches & we're going to cut out the corners as illustrates below and fold up the sides to form a box, also illustrated below. F

Elps in maths, 25 cookies have to be divided equally among 4 children.hw ca...

25 cookies have to be divided equally among 4 children.hw can we use elps to answer this question?

Binimial, theory behind the greatest term in the binomial expansion

theory behind the greatest term in the binomial expansion

Strategy for series - sequences and series, Strategy for Series Now t...

Strategy for Series Now that we have got all of our tests out of the way it's time to think regarding to the organizing all of them into a general set of strategy to help us

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd