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

Testing the difference between two sample means-illustration, An observatio...

An observation was made concerning reading abilities of males and females. The observation leads to a conclusion that females are faster readers than males. The observation was bas

probability: complying with this treatment, A national study found that tr...

A national study found that treating people appropriately for high blood pressure decreased their overall mortality rate by 20%. Treating people adequately for hypertension has bee

Determination of the regression equation, Determination of the Regression E...

Determination of the Regression Equation The determination of the regression equation such given above is generally done by using a technique termed as "the method of least sq

Mean and standard deviation , A professor is interested in decisive if atte...

A professor is interested in decisive if attending college influences the level at which an individual cooperates with the police. The professor is not sure  if attending college w

Explain multiplying-dividing negative fractions, Explain Multiplying/Dividi...

Explain Multiplying/Dividing Negative Fractions? There are 3 steps to multiplying or dividing fractions. 1. If any negative signs are present, place them next to the numerator

Vector functions - three dimensional space, Vector Functions We very f...

Vector Functions We very firstly saw vector functions back while we were looking at the Equation of Lines. In that section we talked about them as we wrote down the equation o

Y=Theea[sin(inTheeta)+cos(inTheeta)], Y=θ[SIN(INθ)+COS(INθ)],THEN FIND dy÷d...

Y=θ[SIN(INθ)+COS(INθ)],THEN FIND dy÷dθ. Solution)  Y=θ[SIN(INθ)+COS(INθ)] applying u.v rule then dy÷dθ={[ SIN(INθ)+COS(INθ) ] dθ÷dθ }+ {θ[ d÷dθ{SIN(INθ)+COS(INθ) ] }    => SI

Statistics, do we calculate midpoints from classes or from class boundaries...

do we calculate midpoints from classes or from class boundaries

Area related to circle, If ABCD isaa square of side 6 cm find area of shad...

If ABCD isaa square of side 6 cm find area of shaded region

Please solve this question, The number of integral pairs (x,y) satisfying t...

The number of integral pairs (x,y) satisfying the equation x^2=y^2+1294 is a)2 b)3 c)4 d)None of these

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