COLLECTION, CLASSIFICATION AND TABULATION OF DATADIAGRAMMATIC AND GRAPHIC REPRESENTATION OF DATAINTRODUCTION

COLLECTION, CLASSIFICATION AND TABULATION OF DATA

DIAGRAMMATIC AND GRAPHIC REPRESENTATION OF DATA

INTRODUCTION

Statistics deals with the collection, classification, presentation, analysis and interpretation of numerical data. Raw data in its original form is difficult to understand. Therefore, it must be systematically collected, classified, tabulated and presented through diagrams and graphs for better understanding and decision-making.

1. COLLECTION OF DATA

Collection of data refers to the process of gathering information for a specific purpose.

Objectives of Data Collection

To obtain relevant and reliable information

To facilitate analysis and interpretation

To help in decision-making and planning

Types of Data

(a) Primary Data

Primary data are collected by the investigator for the first time.

Methods of collecting primary data:

Direct Personal Investigation – Investigator personally collects data

Indirect Oral Investigation – Data collected through witnesses

Questionnaire Method – Respondents fill in questionnaires

Schedule Method – Enumerators fill schedules

Merits:

Original and reliable

Collected for a specific purpose

Demerits:

Time-consuming

Costly

(b) Secondary Data

Secondary data are already collected by someone else.

Sources:

Government publications

Census reports

Journals, books, newspapers

Websites and research reports

Merits:

Economical

Easily available

Demerits:

May be outdated

Not always suitable

2. CLASSIFICATION OF DATA

Classification means arranging data into homogeneous groups or classes based on common characteristics.

Objectives of Classification

To simplify large data

To bring out similarities and differences

To make data suitable for analysis

Types of Classification

Chronological Classification

Data arranged according to time (years, months)

Geographical Classification

Data arranged according to place (state, country)

Qualitative Classification

Based on attributes like gender, literacy, religion

Quantitative Classification

Based on numerical values such as age, income

3. TABULATION OF DATA

Tabulation is the systematic presentation of data in rows and columns.

Objectives of Tabulation

To present data in a concise form

To facilitate comparison

To aid statistical analysis

Parts of a Statistical Table

Table number

Title

Column headings

Row headings

Body

Footnote

Source

Types of Tables

Simple Table

Double Table

Complex Table

Diagrammatic representation presents data in a visual form, making it attractive and easy to understand.

(a) Line Diagram

Data points plotted and joined by straight lines

Used to show changes over time

Merits:

Simple and effective

Shows trend clearly

(b) Bar Diagraml

Bars of equal width with heights proportional to values.

Types of Bar Diagrams:

Simple Bar Diagram – One variable

Multiple Bar Diagram – Two or more variables

Sub-divided Bar Diagram – Components of a total

Uses:

Comparison between different categories

(c) Pie Diagram

A circular diagram divided into sectors showing proportions.

Formula:

Merits:

Attractive

Shows percentage distribution

Demerits:

Not suitable for large data

5. GRAPHIC REPRESENTATION OF DATA

(a) Histogram

Graph of continuous frequency distribution

Rectangles touch each other

Class intervals on X-axis, frequency on Y-axis

Uses:

Shows shape of distribution

Helps in drawing frequency polygon

(b) Frequency Polygon

Constructed by joining midpoints of class intervals

Can be drawn with or without histogram

Uses:

Comparison of distributions

(c) Frequency Curve

Smooth freehand curve passing through frequency polygon points

Represents the general trend of data

(d) Ogives (Cumulative Frequency Curves)

Types:

Less Than Ogive – Cumulative frequencies less than upper limits

More Than Ogive – Cumulative frequencies more than lower limits

Uses of Ogives:

To find Median

To determine Quartiles and Percentiles

CONCLUSION

Collection, classification, tabulation and presentation of data are essential steps in statistics. Diagrammatic and graphic representations simplify complex numerical data and make interpretation easy, meaningful and effective.

1. Collection of Data

1. Primary data are those which are

A) Already published

B) Collected by the investigator for the first time

C) Collected by government agencies

D) Taken from journals

✅ Answer: B

2. Which of the following is a source of secondary data?

A) Questionnaire

B) Schedule

C) Census report

D) Personal interview

✅ Answer: C

3. Data collected through indirect oral investigation are obtained from

A) Respondents

B) Investigators

C) Witnesses

D) Enumerators

✅ Answer: C

2. Classification of Data

4. Arrangement of data according to time is called

A) Qualitative classification

B) Quantitative classification

C) Geographical classification

D) Chronological classification

✅ Answer: D

5. Classification based on attributes like literacy or gender is

A) Quantitative

B) Qualitative

C) Chronological

D) Geographical

✅ Answer: B

6. Income classification belongs to

A) Qualitative classification

B) Geographical classification

C) Quantitative classification

D) Chronological classification

✅ Answer: C

3. Tabulation of Data

7. Systematic presentation of data in rows and columns is called

A) Classification

B) Collection

C) Tabulation

D) Diagram

✅ Answer: C

8. The main objective of tabulation is to

A) Increase data

B) Simplify data

C) Distort data

D) Hide data

✅ Answer: B

9. Which of the following is NOT a part of a statistical table?

A) Title

B) Footnote

C) Graph

D) Source

✅ Answer: C

4. Diagrammatic Representation

10. Which diagram is best for showing changes over time?

A) Pie diagram

B) Bar diagram

C) Line diagram

D) Histogram

✅ Answer: C

11. Bars in a bar diagram are

A) Of unequal width

B) Of equal width

C) Touching each other

D) Circular

✅ Answer: B

12. Pie diagram represents data in terms of

A) Angles

B) Lines

C) Bars

D) Rectangles

✅ Answer: A

5. Graphic Representation

13. Histogram is used for

A) Discrete data

B) Qualitative data

C) Continuous data

D) Percentage data

✅ Answer: C

14. In a histogram, rectangles

A) Do not touch each other

B) Touch each other

C) Are circular

D) Are triangular

✅ Answer: B

15. Frequency polygon is constructed by joining

A) Lower limits of classes

B) Upper limits of classes

C) Midpoints of class intervals

D) Frequencies

✅ Answer: C

16. A smooth curve drawn through the points of a frequency polygon is called

A) Ogive

B) Histogram

C) Frequency curve

D) Bar diagram

✅ Answer: C

6. Ogives

17. Ogive is also known as

A) Frequency curve

B) Cumulative frequency curve

C) Line graph

D) Histogram

✅ Answer: B

18. How many types of ogives are there?

A) One

B) Two

C) Three

D) Four

✅ Answer: B

19. Ogives are used to find

A) Mean

B) Mode

C) Median

D) Range

✅ Answer: C

20. More than ogive is drawn using

A) Upper class limits

B) Lower class limits

C) Class midpoints

D) Frequencies only

✅ Answer: B