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 curve on the surface - shortest arc lenght, (a) Find the curve on ...

(a) Find the curve on the surface z=x 3/2 joining the points(x,y,z)=(0,0,0) and (1,1,1) has the shortest arc lenght? (b) Use a computer to produce a plot showing the surface an

Detremine the rectilinear distance, Rectilinear Distance (Total Travel Dist...

Rectilinear Distance (Total Travel Distance per Day Using Rectilinear Distance): It can be computed through using following formula: d(X, Pi) = |x - ai| + |y - bi| (Source: T

Power regression, how can i solve a multi variable power regression equatio...

how can i solve a multi variable power regression equation..? EX: y=a*(x1^b)*(x2^c).... i need to solve with 4 variable....

Explain the counting principle in maths, Explain the Counting Principle in ...

Explain the Counting Principle in maths? The fundamental counting principle is used when you want to calculate the total number of possible outcomes (or combinations) of an exp

First and second order derivative, Solution : We'll require the first and s...

Solution : We'll require the first and second derivative to do that. y'(x) = -3/2x -5/2                                     y''(x) = 15/4x -7/2 Plug these and also the funct

Example on abels theorem, Without solving, find out the Wronskian of two so...

Without solving, find out the Wronskian of two solutions to the subsequent differential equation. t 4 y'' - 2t 3 y' - t 8 y = 0 Solution : First thing that we want to d

A fire in a building b is reported on telephone, A fire in a building B is ...

A fire in a building B is reported on telephone to two fire stations P and Q, 10km apart from each other on a straight road.  P observes that the fire is at an angle of 60 o to th

Geometry, how do you find the length of a parallel line connecting two exte...

how do you find the length of a parallel line connecting two external circles of different sizes from the outside, given the value of both radius and one parallel line.

What percent the girls surveyed said that area hockey sport, 450 girls were...

450 girls were surveyed about their favorite sport, 24% said in which basketball is their favorite sport, 13% said in which ice hockey is their favorite sport, and 41% said which s

Determine matrix of transformation for orthogonal projection, Determine the...

Determine the matrix of transformation for the orthogonal projection onto the line L that passes through the origin and is in the direction Û=(3/13 , 4/13 , 12/13). Determine the r

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