Advertisements
Advertisements
Question
State the two normal equations used in fitting a straight line
Advertisements
Solution
The constants ‘a’ and ‘b’ are estimated by solving the following two normal Equations
`sum"Y"` = na + `"b"sum"X"` .........(2)
`sum"XY" = "a"sum"X" + "b"sum"X"^2` .........(3)
Where ‘n’ = Number of years given in the data.
APPEARS IN
RELATED QUESTIONS
Define secular trend
Write a brief note on seasonal variations
Explain cyclic variations
The sales of a commodity in tones varied from January 2010 to December 2010 as follows:
| In Year 2010 | Sales (in tones) |
| Jan | 280 |
| Feb | 240 |
| Mar | 270 |
| Apr | 300 |
| May | 280 |
| Jun | 290 |
| Jul | 210 |
| Aug | 200 |
| Sep | 230 |
| Oct | 200 |
| Nov | 230 |
| Dec | 210 |
Fit a trend line by the method of semi-average
Choose the correct alternative:
Factors responsible for seasonal variations are
Choose the correct alternative:
The additive model of the time series with the components T, S, C and I is
Choose the correct alternative:
Least square method of fitting a trend is
Choose the correct alternative:
The value of ‘b’ in the trend line y = a + bx is
A bullet of mass m and velocity a is fired into a large block of wood of mass M The final velocity of the system is
Sum of n terms of series 1.3 + 3.5 + 5.7 + ______ is
