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

Distance and Section Formulae, find the coordinates of points of tri-sectio...

find the coordinates of points of tri-section of the line joining the points (-3,0) and (6,6).

Find out the greater of two consecutive positive is 143, Find out the great...

Find out the greater of two consecutive positive odd integers whose product is 143. Let x = the lesser odd integer and let x + 2 = the greater odd integer. Because product is a

John and charlie have a whole of 80 dollars he has x dollar, John and Charl...

John and Charlie have a whole of 80 dollars. John has x dollars. How much money does Charlie have? This problem translates to the expression 42 + (11 - 9) ÷ 2. Using order of o

Decomposing polygons to find area, find the area of this figure in square m...

find the area of this figure in square millimeter measure each segment to the nearest millmeter

One-to-one correspondence in learning maths, How does your answer to this q...

How does your answer to this question compare with mine, which follows? i) To begin with, 1 laid the beads out in a row for counting, so that I wouldn't leave any out or count a

Learning and formulating maths teaching strategies, Before going further, l...

Before going further, let us repeat an aspect of learning which is useful to keep in mind while formulating teaching strategies. A child who can add or subtract in the context of s

Calculus, What is the slope of the line tangent to f(x)=3-2 ln(2x^2+4) at t...

What is the slope of the line tangent to f(x)=3-2 ln(2x^2+4) at the point (4, f(4))

Operation reserach, advantages oh north west corner rule

advantages oh north west corner rule

Prepare a bar diagram, Question Write a short note on the following: ...

Question Write a short note on the following: 1 The weekly salaries of a group of employees are given in the following table. Find the mean and standard deviation of the

Sketch the direction field for the differential equation, Sketch the direct...

Sketch the direction field for the subsequent differential equation. Draw the set of integral curves for this differential equation. Find out how the solutions behave as t → ∞ and

Write Your Message!

Name

Email id

Message

Verfication Code

User Account

All Pages