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

How many square centimeters are in one square meter, How many square centim...

How many square centimeters are in one square meter? There are 100 cm in a meter. A square meter is 100 cm through 100 cm. The area of this is 10,000 sq cm (100 × 100 = 10,000)

Matrices, find inverse of [1 2 3 2 4 5 3 5 6]

find inverse of [1 2 3 2 4 5 3 5 6]

What is the limit of sin (1/x) when x tends to zero?, As x tends to zero th...

As x tends to zero the value of 1/x tends to either ∞ or -∞. In this situation we will not be sure about the exact value of 1/x. As a result we will not be sure about the exact/app

Negative Numbers, -3+4 #Minimum 100 words accepted#

-3+4 #Minimum 100 words accepted#

Describe real numbers, Q. Describe Real numbers? Ans. There are a ...

Q. Describe Real numbers? Ans. There are a few different ways to describe real numbers. Without going into any of the very technical definitions used by mathematicians, I'

Profit, A wholesaler allows a discount of 20% on the list price to a retail...

A wholesaler allows a discount of 20% on the list price to a retailer. The retailer sells at 5% discount on the list price.If a customer paid Rs 114 for an article,what profit is m

Find homeomorphisms - complex root, All numbers refer to exercises (and not...

All numbers refer to exercises (and not "computer exercises") in Gallian. §22: 8, 16, 22, 24, 28, 36. In addition: Problem 1: Let a be a complex root of the polynomial x 6 +

Queuing Theory, A telephone exchange has two long distance operators.The te...

A telephone exchange has two long distance operators.The telephone company find that during the peak load,long distance calls arrive in a poisson fashion at an average rate of 15 p

Sum, i want to trick to know how can i fastest calculate more than compute...

i want to trick to know how can i fastest calculate more than computer

Integers, Whats some negative integers that equal 36

Whats some negative integers that equal 36

Write Your Message!

Name

Email id

Message

Verfication Code

User Account

All Pages