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 8^th 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 8^th year sales = 12 + 1.86 (8)

=26.88 that is 26,888 units.

Related Discussions:- Forecasting by using least squares

Solution by quadratic formula, Help me how to solve equation by Quadratic F...

Help me how to solve equation by Quadratic Formula.

Ineqaulites, how to work out inequalities with negative signs?

how to work out inequalities with negative signs?

Objective functions, For schedule consistency, you decide to require each o...

For schedule consistency, you decide to require each officer to report for their eight-hour shift at 12 AM, 4 AM, 8 AM, 12 PM, 4 PM, or 8 PM. As the Director of Public Safety, you

The point which divides a gven line - segment externally, The point which d...

The point which divides a gven line - segment externally: Construction : i )Draw BX making an actue angle at B. ii) Starting from B mark three equal points on BX as sh

Logarithm., What is log3(x+1)

What is log3(x+1)

Trigonometry, Prove: 1/cos2A+sin2A/cos2A=sinA+cosA/cosA-sinA

Prove: 1/cos2A+sin2A/cos2A=sinA+cosA/cosA-sinA

Boeing Company and Ingredient Branding Strategies, . The Boeing Company ma...

. The Boeing Company makes a number of different types of aircraft for the commercial airline industry, e.g., the 727, 747, 757, 767, and 777 jet models. Is there any way for Boei

Derivatives of hyperbolic functions , Derivatives of Hyperbolic Functions ...

Derivatives of Hyperbolic Functions : The last set of functions which we're going to be looking at is the hyperbolic functions. In several physical situations combinations of e

How to calculate arithmetic average or mean, Q. How to calculate arithmetic...

Q. How to calculate arithmetic average or mean? Ans. When people collect information, or data, they can easily be overwhelmed with information. Just imagine listing the b

Geometry, geometry fbw = 128 saf= 104 what is rfd

geometry fbw = 128 saf= 104 what is rfd

Write Your Message!

Name

Email id

Message

Verfication Code

User Account

All Pages