The Components of Time Series
The factors that are responsible for bringing about changes in a time series, also called the components of time series,… Click here to read more
The factors that are responsible for bringing about changes in a time series, also called the components of time series,… Click here to read more
The objective of the time series analysis is to identify the magnitude and direction of trends, to estimate the effect… Click here to read more
A number of different methods are available to estimate the trend; however, the suitability of these methods largely depends on… Click here to read more
This is a familiar concept, and is briefly described for drawing frequency curves. In case of a time series a… Click here to read more
Advantages This method is very simple and easy to understand. It is applicable to linear and non-linear trends. It gives… Click here to read more
This method is as simple and relatively objective as the free hand method. The data is divided in two equal… Click here to read more
Advantages This method is very simple and easy to understand, and also it does not require many calculations. Disadvantages The… Click here to read more
Suppose that there are $$n$$ time periods denoted by $${t_1},{t_2},{t_3}, \ldots ,{t_n}$$ and the corresponding values of the $$Y$$ variable… Click here to read more
Advantages Moving averages can be used for measuring the trend of any series. This method is applicable to linear as… Click here to read more
Using the multiplicative model, i.e.$$Y = T \times S \times R$$, the ratio detrended series may be obtained by dividing… Click here to read more
Using the additive model, i.e. $$Y = T + S + R$$, the de-trended series may be obtained by subtracting… Click here to read more
The long term cyclical movements in a time series can be studied more or less in the same way as… Click here to read more
Mathematical curve fitting is probably the most objective method of isolating trends. This method enables us to obtain precise estimates… Click here to read more
The time series data which is recorded after a regular or irregular interval of time consists of values of a… Click here to read more
Lagrange’s formula is applicable to problems where the independent variable occurs at equal and unequal intervals, but preferably this formula… Click here to read more
Example No 1: Interpolate the value of the function corresponding to $$X = 4$$ using Lagrange’s interpolation formula from the… Click here to read more
A number of different formulae were given by Newton, however two of these formulae are more common. One of these… Click here to read more
Example No 1: The following supply schedule gives the quantities supplied $$\left( S \right)$$ in hundreds of a product at… Click here to read more
When the values of the independent variable occur with unequal spacing, the formula discussed earlier is no longer applicable. In… Click here to read more