Applied Maths 2 Marks Questions

The effect of long term causes is reflected in the tendency of a behaviour, to move in an upward or downward direction, termed as Trend or Secular Trend.
The secular trends could reflect environmental improvements, specifically changes in health practice and living conditions leading to improvements in mortality rates and life expectancy. These factors are interrelated with those concerning family size.

Secular Trend: It is a general tendency, of time series to increase or decrease or stagnates during a long period of time. An upward tendency is usually observed in the population of a country, production, sales, prices in industries, the income of individuals etc., A downward tendency is observed in deaths, epidemics, prices of electronic gadgets, water sources, mortality rate etc.
Seasonal Variations: Seasonal variations refer to the changes that take place due to the rhythmic forces which operate in a regular and periodic manner. These forces usually have the same or most similar pattern year after year. When we record data weekly, monthly or quarterly, we can see and calculate seasonal variations. Thus, when a time series consists of data only based on annual figures, there will be seen no seasonal variations. These variations may be due to seasons, weather conditions, habits, customs or traditions. For example, selling of umbrellas and raincoats in the rainy season, sales of cold drinks in the summer season, crackers in Deepawali season, purchase of dresses in a festival season, sugarcane in Pongal season.

We should study time series for the following reasons:
(i) It helps in the analysis of past behaviour.
(ii) It helps in forecasting and for future plans.
(iii) It helps in the evaluation of current achievements.
(iv) It helps in making comparative studies between one time period and others.
Therefore time series helps us to study and analyse the time-related data which involves in business fields, economics, industries, etc.

Time series analysis is used for many applications such as: Economic Forecasting, sales forecasting, Budgetary Analysis etc.

Business forecasting refers to the tool and techniques used to predict developments in business, such as sales, expenditures and profits. The purpose of business forecasting is to develop better strategies based on these informed predictions.

There are four types of components in a time series.
(i) Secular Trend
(ii) Seasonal variations
(iii) Cyclic variations
(iv) Irregular variations

A time-series carries profound importance in business and policy planning. It is used to compare the current trends with that in the past or the expected trends. Thus it gives a clear picture of growth or downfall. Most of the time series data related to fields like Economics, Business, Commerce etc. For example the production of a product, cost of a product, sales of a product, national income, salary of an individual etc. By close observation of time series data, one can predict and plan for future operations in industries and other fields.

A Time Series consists of data arranged chronologically - Croxton Cowden.
When quantitative data are arranged in the order of their occurrence, the resulting series is called the Time Series. - Wessel Wallet