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

Solve simultaneous equations by graphical method, Solve the following pairs...

Solve the following pairs of simultaneous equations by elimination method i.2x+y=10 ii. 3x+y=6 3x-2y=1 5x+y=8 solve the following simult

Find the return period in years of the critical event, 1. A drainage system...

1. A drainage system overflows into a river causing pollution when the rainfall falling in an hour exceeds 50 mm. During any given year, the maximum hourly rainfall follows an expo

the bug should start to move in order to increase, The temperature at the ...

The temperature at the point (x, y) on a metal plate is given by the function f(x, y) = x 3 + 4xy + y 2 where f is in degrees Fahrenheit and x and y are in inches, with the origin

find the present age, 5 years however, a man's age will be 3times his son'...

5 years however, a man's age will be 3times his son's age and 5 years ago, he was 7 times as old as his son.    Find their present ages.

Example of cartesian coordinate graph, Example of Cartesian coordinate Grap...

Example of Cartesian coordinate Graph: Example:   The temperature of water flowing in a high pressure line was measured at regular intervals.  Plot the subsequent recorded da

Binomial probability distribution, Binomial Probability Distribution B...

Binomial Probability Distribution Binomial probability distribution is a set of probabilities for discrete events. Discrete events are those whose outcomes or results can be c

Maths, f all the permutations of the letters of the word chalk are written ...

f all the permutations of the letters of the word chalk are written in a dictionary the rank of this word will be?

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