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

Daily Math, Six times as many people voted in the 2012 election as in the 2...

Six times as many people voted in the 2012 election as in the 2008 election.If 162 people voted in 2008,how many people voted in both elections?

Determine the function notation, Given f (x) = - x 2 + 6 x -11 determine e...

Given f (x) = - x 2 + 6 x -11 determine each of the following. (a)    f ( 2) (b)   f ( -10) (c)    f (t ) Solution (a)    f ( 2) = - ( 2) 2   + 6(2) -11 = -3 (

Division, Why do we start dividion operation from left to right?

Why do we start dividion operation from left to right?

In how many years is the population expected to be 42, The population of a ...

The population of a particular city is increasing at a rate proportional to its size. It follows the function P(t) = 1 + ke 0.1t where k is a constant and t is the time in years.

Properties of triangle, In triangle ABC, cosecA(sinB.sinC+cosB.sinC) is equ...

In triangle ABC, cosecA(sinB.sinC+cosB.sinC) is equal to..?

Equivalent Fractions and Decimals, write each fraction as a decimal .round ...

write each fraction as a decimal .round to the nearest hundredth if necessary (1-4) (14-21)

Times tables, how can you memorise you times facts

how can you memorise you times facts

Properties of relations in a set, Reflexive Relations: R is a reflexive...

Reflexive Relations: R is a reflexive relation if (a, a) € R,  a € A. It could be noticed if there is at least one member a € A like (a, a) € R, then R is not reflexive. Sy

How to left shifts and right shifts a graph, Q. How to Left shifts and righ...

Q. How to Left shifts and right shifts a graph? Ans. When you're translating (shifting) a graph, it's easy to get subtracting and adding mixed up. It seems counter-intuiti

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