Page 104 - Ganit Kaushal

Advantages of Primary Data

• It is accurate and reliable because it comes directly from the source.
• It is collected with a specific purpose in mind, making it relevant to your needs.

Disadvantages of Primary Data

• It can be time-consuming and expensive to collect.
• It may require a lot of effort to gather information from many sources.

Secondary Data

Secondary data is the information that is obtained from an already published source. It was originally collected
and recorded by someone else. It is second-hand data, which means you use information that already exists,
usually found in books, reports, websites, or other published sources.
Examples:
• Data from a newspaper report on the results of a city’s election.

• A graph from a website showing the population of India over the past decade.
Advantages of Secondary Data

• It is easier and faster to obtain because it is already collected.
• It is often less expensive than gathering primary data.

Disadvantages of Secondary Data

• It may not be exactly what you need because it was collected for a different purpose.
• It can sometimes be outdated or less reliable, depending on the source.

Organising Data

The data as given in the above table by Navya, which has been collected but not organised and summarised,
is referred to as Raw or Ungrouped Data.
Raw or ungrouped data is huge and confusing. As such, it may not be easily understood by persons and is not
fit for further analysis and interpretation. So, after collecting the data, the next important step is to organise it
systematically.

Sometimes the data can be organised and analysed by putting it in ascending or descending order. The difference
between the highest and the lowest values of the observations in a data set is called the Range of the data.

To make data understandable, we have to present the raw or ungrouped data in the form of tables and graphs. Data
are tabulated to bring out clearly the points of similarity and dissimilarity and to facilitate easy interpretation.
In order to do that, we will learn here three methods of organising and analysing the data:

(1) Tally-Mark Tables, (2) Bar Graphs and (3) Pictographs

4.3 TALLY MARK TABLES (Frequency Distribution Table)

Consider the above table of raw data collected by Navya by asking each of her classmates about their favourite
game. Now, to put the given raw data in tabular form, we make three columns in a table. One for the ‘name of

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