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  OPERATION RESEARCH FUNDAMENTALS FOR BUSINESS OPERATION RESEARCH Operation Research  Operation Research is a discipline that helps to make better decisions in complex scenarios by the application of a set of advanced analytical methods.  It couples theories, results and theorems of mathematics , statistics and probability with its own theories and algorithms for problem solving Operation Research is also known as  • Decision Science • Management Science • Operation management • Quantitative Techniques

The values of a time series may be affected by the number of movements or fluctuations, which are its characteristics. The types of movements characterizing a time series are called components of time series or elements of a time series. These are four types Secular Trend  Seasonal Variations  Cyclical Variations  Irregular Variations  Secular Trend  Secular Trend is also called long term trend or simply trend. The secular trend refers to the general tendency of data to grow or decline over a long period of time. For example the population of India over years shows a definite rising tendency. The death rate in the country after independence shows a falling tendency because of advancement of literacy and medical facilities. Here long period of time does not mean as several years. Whether a particular period can be regarded as long period or not in the study of secular trend depends upon the nature of data. For example if we are studying the figures of sales of cloth ...

  The essential requirements of a time series are:  The time gap, between various values must be as far as possible, equal. It must consist of a homogeneous set of values.  Data must be available for a long period.  Symbolically if „t‟ stands for time and 'yt' represents the value at time t then the paired values (t, yt) represents a time series data.

 

  CENSUS VS SAMPLE SURVEY Census Census method is the method of statistical enumeration where  all members of the population  are studied. A population refers to the set of all observations under concern. For example, if you want to carry out a survey to find out student’s feedback about the facilities of your  school , all the students of your school would form a part of the ‘population’ for your study. In our country, the Government conducts the  Census of India  every ten years. The Census appropriates information from households regarding their incomes, the earning members, the total number of children, members of the family, etc. This method must take into account all the units. It cannot leave out anyone in collecting  data. Once collected, the Census of India reveals  demographic information  such as birth rates, death rates, total population,  population growth rate of our country , etc. The last census was conducted in th...

COLLECTION OF SECONDARY DATA Sources of secondary data We know that secondary data are those which have already been collected and analysed by someone else, and as such the problems associated with the original collection of data do not arise here. Secondary data may be either published or unpublished. The sources of published data are usually:- (a) Official publications of the central, state and the local governments. (b) Official publications of the foreign government or international bodies like the United Nations Organization and its subsidiary bodies. (c) Reports and publications of trade associations, chambers of commerce, banks, co-operative societies, stock exchanges, and trade unions, etc. (d) Technical trade journals like the Economics, Indian Journal of Economics, Commerce, Capital, etc., and books and newspapers. (e) Reports submitted by economists, research scholars, university bureaus and various other educational associations, etc.    

  There are two sources of collecting the data 1.       Primary data 2.       Secondary data   Primary data are those which are collected for the first time and are thus original in character, whereas Secondary data are those that have already been collected by others and which ate usually available in journals, magazines or research publications . Primary data are in the shape of raw materials to which statistical methods are applied for the purpose of analysis and interpretation. Secondary data are usually in the shape of finished products since they have been treated statistically in some form or the other. Factors affecting choice of method. It is obvious that the methods of the collection of primary data and secondary data would not be exactly identical because in one case the data have to be originally collected while in the other the work is of the nature of compilation. There are various methods of the collect...