NTA UGC NET - Commerce: UNIT 05: Business Statistics and Research Methods - PART 04

 NTA UGC NET - Commerce

UNIT 05

Business Statistics and Research Methods

PART 04

 

Data - Collection and Classification

 

> Usually, the terms “data” and “information” are used interchangeably. However, there is a subtle difference between the two.
> Data is a collection of raw, unorganised facts and details like text, observations, figures, symbols and description of things etc
> Information is the processed, organised and structured data

> Information is sufficient for decision making
 

Data collection is a process of gathering information from all the relevant sources to find a solution to the research problem.
 

Data can be classified into two types, namely primary data and secondary data.
 

Primary Data Collection Methods
 

Primary data or raw data is a type of information that is obtained directly from the first-hand source through experiments, surveys or observations. 

 

The primary data collection method is further classified into two types. They are
 

Quantitative Data Collection Methods (Objectivist)
Qualitative Data Collection Methods (Subjectivist)
 

Quantitative Data Collection Methods 

 

It is based on mathematical calculations using various formats like close-ended questions, correlation and regression methods, mean, median or mode measures. This method is cheaper than qualitative data collection methods and it can be applied in a short duration of time.

Qualitative Data Collection Methods

 
It does not involve any mathematical calculations. This method is closely associated with elements that are not quantifiable. This qualitative data collection method includes interviews, questionnaires, surveys, observations, case studies, etc.
 

Secondary Data Collection Methods
 

Secondary data is data collected by someone other than the actual user. It means that the information is already available, and someone analyses it. The secondary data includes magazines, newspapers, books, journals, etc. It may be either published data or unpublished data.
 

Published data are available in various resources including
_ Government publications
_ Public records
_ Historical and statistical documents
_ Business documents
_ Technical and trade journals
 

Unpublished data includes
_ Diaries
_ Letters
_ Unpublished biographies, etc.
 

All the original data collected by analyst themselves fall in the category of primary data. Secondary data are those which are available for use from other sources.
 

Classification of data

 
The method of arranging data into similar groups according to the common features present in the data is known as classification.

BASIS OF CLASSIFICATION:

 

(1) Geographical classification

 

● When data are classified with reference to geographical locations such as countries, states, cities, districts, etc., it is known as geographical classification. 

● It is also known as ‘spatial classification’.

(2) Chronological classification

 

● A classification where data are grouped according to time is known as a chronological classification. 

● In such a classification, data are classified either in ascending or in descending order with reference to time such as years, quarters, months, weeks, etc. 

● It is also known as temporal classification’.

(3) Qualitative classification

 

● Under this classification, data are classified on the basis of some attributes or qualities like honesty, beauty, intelligence, literacy, marital status, etc. 

● For example, the population can be divided on the basis of marital status (as married or unmarried)

(4) Quantitative classification

 

● This type of classification is made on the basis of some measurable characteristics like height, weight, age, income, marks of students, etc.

 

Statistical series
 

Statistical series is a systematic arrangement of statistical data in some logical order.
On the basis of general characteristics, statistical series are of three kinds:
 

(i) Time series (Chronological series)
 

If the different values that a variable has taken in a period of time are arranged in a chronological order, the series so obtained is known as a time series.
 

(ii) Spatial series (Geographical series)

 
The data arranged according to location or geographical considerations form a spatial series.
 

(iii) Condition series

 

In this series, data are classified according to the changes occurring in variables according to a condition, such as height, weight, age, marks, income, etc.

According to construction, statistical series can be categorised as :

Types of continuous series

 
Class’ means a group of numbers, in which items are placed, such as 0–-10, 10–-20, 20–-30, etc

The two extreme values of each class are known as the class limits.

● The lowest value is termed as the ‘lower limit’ (l1), and the highest value is known as the upper limit’ (l2) of the class.
 

● For example, in the class “5–-10”, 5 is the lower limit (l1) and 10 is the upper limit (l2).
 

● The difference between the upper limit (l2) and the lower limit (l1) of a class is known as the magnitude of the class or class size.
 

● For example, in the class -interval 20–-50, the magnitude of class -interval is (l2– l1), i.e., 50 – 20 = 30.
Frequency refers to a number of times a given value appears in a distribution
 

A table, in which the frequencies and the associated values of a variable are written side by side, is known as a frequency distribution.
 

(A) Exclusive series –
 

● Frequency distribution having classes wherein:
 

● The upper limit of one class becomes the lower limit of the next class.
 

(B) Inclusive series
 

● Frequency distribution having classes wherein:
 

● The upper limit of one class is not equal to the lower limit of the next class.
 

(C) Mid- value series
 

● Mid- value = (l1 + l2) ÷ 2
 

● Mid-value or mid-point is the central value of a class -interval.
(D) Open- ended series (Distribution)
 

● In a frequency distribution, if the lower limit (l1) of the first class and the upper limit (l2) of last class are not given, then it is known as “open-ended distribution”.
 

(E) Continuous series with unequal intervals
 

● When the class size, i.e., the gap between (l2) and (l1), is not equal in all the classes, it is known as unequal class interval series.

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