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

Setup the mass balance equation - linear system method, Two tanks initially...

Two tanks initially contain 100 liter liquid each. Their initial concentration are listed in the Figure below. At time zero, the input and output valves are opened simultaneously w

Graphing sets of numbers, Q. Graphing Sets of Numbers? Ans. To  gr...

Q. Graphing Sets of Numbers? Ans. To  graph  a set of numbers on a number line means to plot, or locate, those positions on the line. The number that corresponds to a poin

Solve 5x tan (8x ) =3x trig function, Solve 5x tan (8x ) =3x . Solution...

Solve 5x tan (8x ) =3x . Solution : Firstly, before we even begin solving we have to make one thing clear.  DO NOT CANCEL AN x FROM BOTH SIDES!!! Whereas this may appear like

Properties of integer exponents, Note that there are two possible forms for...

Note that there are two possible forms for the third property. Usually which form you use is based upon the form you want the answer to be in. Note as well that several of these

Determine randomly generated bit string, Assume E is the event that a rando...

Assume E is the event that a randomly generated bit string of length 4 starts with a 1 and F is the event that this bit string consists of an even number of 1's. Are E and F indepe

Integral calculus, how to change order and variable in multiple integral

how to change order and variable in multiple integral

1234 Mathematics, use only the digits 1,2,3 and 4 in any order to write an ...

use only the digits 1,2,3 and 4 in any order to write an expression for the numbers 1 to 100. you may only use each digit once. You may use exponents of 1,2,3 and 4 in some of th

probability that the card is a 8 or an ace, A standard deck of cards conta...

A standard deck of cards contains 52 cards. One card is selected at random. Determine a)    The probability that the card is a 8 or an Ace? b)    The probability that the card is

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