STATISTICS
HIGHER SECONDARY – FIRST YEAR
Untouchability is a sin
Untouchability is a crime
Untouchability is inhuman
TAMILNADU
TEXTBOOK CORPORATION
College Road , Chennai- 600 006
i
,©Government of Tamilnadu
First Edition – 2004
Reprinit - 2005
Chairperson
Dr. J. Jothikumar
Reader in Statistics
Presidency College
Chennai – 600 005.
Reviewers
Thiru K.Nagabushanam Thiru R.Ravanan
S.G.Lecturer in Statistics S.G.Lecturer in Statistics
Presidency College Presidency College
Chennai – 600 005. Chennai – 600 005.
Authors
Tmt. V.Varalakshmi Tmt. N.Suseela
S.G.Lecturer in Statistics P.G.Teacher
S.D.N.B. Vaishnav College Anna Adarsh Matric
for women Hr. Sec. School
Chrompet, Annanagar,
Chennai – 600 044. Chennai–600 040.
Thiru G.Gnana Sundaram Tmt.S.Ezhilarasi
P.G.Teacher P.G.Teacher
S.S.V. Hr. Sec. School P.K.G.G. Hr. Sec. School
Parktown, Chennai – 600 003. Ambattur, Chennai–600 053.
Tmt. B.Indrani
P.G.Teacher
P.K.G.G. Hr. Sec. School
Ambattur, Chennai – 600 053.
Price: Rs.
This book has been prepared by the Directorate of School
Education on behalf of the Government of Tamilnadu.
This book has been printed on 60 G.S.M paper
Printed by offset at:
ii
, CONTENTS Page
1. Definitions, Scope and Limitations 1
2. Introduction to sampling methods 11
3. Collection of data,
Classification and Tabulation 28
4. Frequency distribution 49
5. Diagramatic and graphical
representation 68
6. Measures of Central Tendency 94
7. Measures of Dispersion,
Skewness and Kurtosis 141
8. Correlation 191
9. Regression 218
10. Index numbers 241
iii
, 1. DEFINITIONS, SCOPE AND
LIMITATIONS
1.1 Introduction:
In the modern world of computers and information
technology, the importance of statistics is very well recogonised by
all the disciplines. Statistics has originated as a science of statehood
and found applications slowly and steadily in Agriculture,
Economics, Commerce, Biology, Medicine, Industry, planning,
education and so on. As on date there is no other human walk of
life, where statistics cannot be applied.
1.2 Origin and Growth of Statistics:
The word ‘ Statistics’ and ‘ Statistical’ are all derived from
the Latin word Status, means a political state. The theory of
statistics as a distinct branch of scientific method is of
comparatively recent growth. Research particularly into the
mathematical theory of statistics is rapidly proceeding and fresh
discoveries are being made all over the world.
1.3 Meaning of Statistics:
Statistics is concerned with scientific methods for
collecting, organising, summarising, presenting and analysing data
as well as deriving valid conclusions and making reasonable
decisions on the basis of this analysis. Statistics is concerned with
the systematic collection of numerical data and its interpretation.
The word ‘ statistic’ is used to refer to
1. Numerical facts, such as the number of people living in
particular area.
2. The study of ways of collecting, analysing and interpreting
the facts.
1.4 Definitions:
Statistics is defined differently by different authors over a
period of time. In the olden days statistics was confined to only
state affairs but in modern days it embraces almost every sphere of
1
HIGHER SECONDARY – FIRST YEAR
Untouchability is a sin
Untouchability is a crime
Untouchability is inhuman
TAMILNADU
TEXTBOOK CORPORATION
College Road , Chennai- 600 006
i
,©Government of Tamilnadu
First Edition – 2004
Reprinit - 2005
Chairperson
Dr. J. Jothikumar
Reader in Statistics
Presidency College
Chennai – 600 005.
Reviewers
Thiru K.Nagabushanam Thiru R.Ravanan
S.G.Lecturer in Statistics S.G.Lecturer in Statistics
Presidency College Presidency College
Chennai – 600 005. Chennai – 600 005.
Authors
Tmt. V.Varalakshmi Tmt. N.Suseela
S.G.Lecturer in Statistics P.G.Teacher
S.D.N.B. Vaishnav College Anna Adarsh Matric
for women Hr. Sec. School
Chrompet, Annanagar,
Chennai – 600 044. Chennai–600 040.
Thiru G.Gnana Sundaram Tmt.S.Ezhilarasi
P.G.Teacher P.G.Teacher
S.S.V. Hr. Sec. School P.K.G.G. Hr. Sec. School
Parktown, Chennai – 600 003. Ambattur, Chennai–600 053.
Tmt. B.Indrani
P.G.Teacher
P.K.G.G. Hr. Sec. School
Ambattur, Chennai – 600 053.
Price: Rs.
This book has been prepared by the Directorate of School
Education on behalf of the Government of Tamilnadu.
This book has been printed on 60 G.S.M paper
Printed by offset at:
ii
, CONTENTS Page
1. Definitions, Scope and Limitations 1
2. Introduction to sampling methods 11
3. Collection of data,
Classification and Tabulation 28
4. Frequency distribution 49
5. Diagramatic and graphical
representation 68
6. Measures of Central Tendency 94
7. Measures of Dispersion,
Skewness and Kurtosis 141
8. Correlation 191
9. Regression 218
10. Index numbers 241
iii
, 1. DEFINITIONS, SCOPE AND
LIMITATIONS
1.1 Introduction:
In the modern world of computers and information
technology, the importance of statistics is very well recogonised by
all the disciplines. Statistics has originated as a science of statehood
and found applications slowly and steadily in Agriculture,
Economics, Commerce, Biology, Medicine, Industry, planning,
education and so on. As on date there is no other human walk of
life, where statistics cannot be applied.
1.2 Origin and Growth of Statistics:
The word ‘ Statistics’ and ‘ Statistical’ are all derived from
the Latin word Status, means a political state. The theory of
statistics as a distinct branch of scientific method is of
comparatively recent growth. Research particularly into the
mathematical theory of statistics is rapidly proceeding and fresh
discoveries are being made all over the world.
1.3 Meaning of Statistics:
Statistics is concerned with scientific methods for
collecting, organising, summarising, presenting and analysing data
as well as deriving valid conclusions and making reasonable
decisions on the basis of this analysis. Statistics is concerned with
the systematic collection of numerical data and its interpretation.
The word ‘ statistic’ is used to refer to
1. Numerical facts, such as the number of people living in
particular area.
2. The study of ways of collecting, analysing and interpreting
the facts.
1.4 Definitions:
Statistics is defined differently by different authors over a
period of time. In the olden days statistics was confined to only
state affairs but in modern days it embraces almost every sphere of
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