Overview of statistics

Pre - Induction Programme

By
Prof. Manisha Phate

In our day to day life statistics conveys a variety
of meanings to people. We find statistics in
newspapers, journals, books, various reports,
speeches, classroom lectures etc.
Example:
There are 940 females per 1000 males in india.
 For population UP in India stands at rank first.
Maharashtra stands at second position
having 9.29% of total population.

INTRODUCTION
 Density of population in Maharashtra is 365
per km square. And the sex ratio is 925
females per 1000 males.
 The literacy rate in Maharashtra is 82.91%.
 Most literate state in india is Kerala with
93.9%.
 Percentage of students whose name is
starting with letter A, B, D, Y,
 The students who scored in
between 50 to 70.

ORIGIN AND GROWTH
ORIGIN
 It is not a new discipline but as old as human society
itself. It has been in use since the existence of life on
earth.
 The word statistics comes from the Italian word statista
(meaning statesman) or the German word statistik
which means a political state.
 It was first used by Prof.Gottfried Achenwall (1719-
1772)
 Achenwall first defined the statistics as the political
science of several countries.
 The word statistics appeared first time in a famous book
– Elements of Universal Erudiction Science of statistics
is originated from two main sources
1. Government Records
2. Mathemetics

Govt. Records
 During good old days it is regarded as the science of
statecraft. Because it was byproduct of the
administrative activity of the state.
 This is earliest foundation because all cultures with a
recorded history had recorded statistics and the
recording as far as is known was done by govt. agents
for governmental purpose.
 It has been in traditional function of govt. to keep
records of population, births, deaths, taxes, crop yields
etc.
 As the data was collected for governmental purposes
statistics was then described as the science of kings or
the science of statecraft.

Statistics is said to be a branch of applied
mathematics.
The present body of statistical methods
particularly those concerned with drawing
inferences about population from sample is based
on the mathematic theories.
Numbers play an important role in statistics and
here the study of statistics involves methods of
refining numerical and non numerical information
in to useful forms.

There has been a phenomenal development
in the use of statistics in several fields.
Now a days it is a most important tool for
taking decisions in case of uncertainty.
Two main factors which are responsible
the development of statistics
1. Increased demand for statistics
2. Decreasing cost of statistics

In present, considerable development has taken place in
the field of business, commerce, governmental activities
and science. Statistics helps in formulating suitable
policies and as such its need is increasingly being felt in
all the spheres. Such as……….
a) Government: As there is enlargement in Govt.
functions
b) Sciences: Tremendous advancement in the existing
sciences & also development of new branches.
c) Research: Extensive research work is now being
undertaken by many people.
d) Time & Cost: Less time & cost to collect and process
the data with the help of electronic machines such as
calculators, computers etc.

Decreasing Cost of Statistics

Following factors helps to decrease the
cost
 Development of statistical theories: eg.
Sampling Techniques
 Use of electronic machines: eg.
Computer calculator
 Tools for Analysis: eg. SPSS

STATISTICS - DEFINITION

There have been many definitions of the term
statistics:
1. Webster: The classified facts representing the
conditions of the people in a state. Especially
those facts which can be stated in numbers
or in tables of numbers or in any tabular
classified arrangement.
2. Yule & Kendall: By statistics we mean
quantitative data affected to a marked extent
by multiplicity of causes.

3 . Horace secrist: Statistics means
aggregates of facts affected to a
marked extent by multiplicity of
causes ,numerically
expressed, estimated according to
reasonable standards of
accuracy, collected in a systematic
manner for a predetermined purpose
and placed in relation to each other.

;

Above definition states certain charactristics which
numerical data must possess in order that they may
be called statistics.
Aggregates of facts:
Affected to a marked extent by multiplicity of
causes
Numerically expressed
Enumerated or estimated according to resonable
standards of accuracy
Collected in a systematic manner
Collected for pre-detemined purpose
Should be placed in Relation to each other.

Croxton and cowden : Statistics may be
defined as the collection, presentation
analysis and interpretation of numerical
data.
Very simple and precise definition and talks
about four stages of Statistics.
 Collection
 Presentation
 Analysis
 Interpretation

Frequently used statistical terms

Data

Statistical
Sample Variable
Terms

Population

Data
 Data: This is simply a group of results of any
scientific measurement.
Eg. Collection of numbers representing height of
students in a class, Marks in a class.

Variable
 This is a characteristic that can assume different
values and is usually represented by x.
 Eg. Age of students, sales figure of a commodity.
Etc.

Population
 A population or universe is the totality
of items or things under consideration.
It is the collection of all values of the
variable under study.
OR
 The complete collection of all elements
(scores, people, measurements, and so
on) to be studied. The collection is
complete in the sense that it includes all
subjects to be studied.

Sample
 It is the portion of population or
universe under consideration. And
sampling is the process of selecting
sample.
OR
 A sub-collection of elements drawn
from a population

STATISTICS: SCIENCE & ART
Its a subject of Debate.
Science: systematized body of knowledge. It studies
cause and effect relationship and attempts to
make generalizations in the form of scientific
principles or laws. It describes objectivity and
avoids vague judgments. Science is Knowledge.
Art: refers to the skill of handling facts so as to
achieve a given objective. Having concern with
ways & means of presenting and handling data
making inferences logically and drawing relevant
conclusions. Art is Action.
Statistics: not a body of knowledge but a body of
methods for obtaining knowledge.

Functions of Statistics

 Presents facts in a definite form
 Simplifies mass of figures
 Facilitates comparison
 Helps in formulating & testing
hypothesis
 Helps in prediction
 Helps in formulation of suitable
policies.

Definiteness
 To present general statements in a precise and
definite form. As numerical statements are
more convincing.

 Example: The production of wheat in India in
2006-07 was higher than that in 2005-06.

 “The production of wheat for the year 2006-07
was 72.5 million tonnes compared to 69.4
million tonnes for 2005-06.”

Condensation
 Helps in condensing mass of data in to
few significant figures. Statistical
methods present a meaningful overall
information from mass of data.

 Example: Income position of people of
India from a record of individual
incomes of the entire population. (Per
capita Income)

Comparison
 Unless figures are compared with
others of same kind they are often
devoid of any meaning.
 Example: The production of rice in
2009-10 is likely to be 100 million
tonnes as compared to 96 million
tonnes in 2008-09.

Formulation & Testing
Hypothesis
 Statistical methods are helpful in
formulating and testing hypothesis & to
develop new theories.
 Example: Hypothesis like whether
chloromycetin is effective in curing typhoid.
Whether students have benefitted from the
extra coaching.etc.
 Technique: Chi-square Test

Prediction
 Plans & policies of organisations are
invaribly formulated well in advance of
the time of their implementation.
Statistical methods provide helpful
means for forecasting future events.
 Example: How much cement should be
produced by a cement company in
coming year.
 Technique: Simulation

Formulation of Policies
 Statistics provide the basic material for
framing suitable policies.
 Example: Data about population- its
distribution by age & sex, rate &
growth of it. Migration, area etc. helps
in determining the future needs such
as
food, clothing, housing, education, recr
eational
facilities, water, electricity, transportati
on, system etc.

Statistics & the State
 Since ancient times the ruling kings chiefs
have relied on statistics in framing suitable
military and fiscal policies. Eg. crimes,
military strength, population, taxes etc.

 Today all ministers and departments of
govt. (Finance, Transport, Defence,
Railway, Food Commerce, Post &
Telegraph, or Agriculture, etc.) depend
heavily on factual data for their efficient
functioning.

Statistics & Business
 With growing size & ever increasing
competition the problems of the business
are becoming complex & they are using
more & more statistics in decision making.
 Business activities can broadly grouped in
to
Production, Purchase, Finance, Personnel,
Accounting, Market & Product
Research, Quality Control.
 Each & every area is rely on statistics for
their effective functioning.

Statistics & Economics
 In the year 1890 Prof.Alfred Marshall the
renowned economist observed that “ Statistics are
the straw out of which I, Like every other
economist, have to make bricks.’’
 Economics is concerned with Production,
Distribution, Consumption, saving & investment
of income.
 Example: What to produce, how to produce, and
for whom to produce – to answer these questions
we need a lot of statistical data in absence of
which it is not possible to arrive at correct
decision.
 Statistics of production help in adjusting the
supply to demand.

Statistics & Economics
 Statistics of consumption enable us to find out the
way in which people of different strata spend there
income.
 To solve the problems of rising prices, growing
population, unemployment, poverty etc. one has to
rely on statistics.
 It plays role not only in formulating of economic
policies but also evaluating their effects.
 We use statistics in Measurement of Gross national
product, Input output analysis, money &
banking, Consumer finance, Public Finance, business
cycles,Competition, oligopoly &
monopoly, comparison of market prices, cost & profit
of individual firms, prices & Population etc.

Statistics & Physical Sciences

Astronomy

Metrology Geology

Physical
Sciences

Engineering Physics

Chemistry

Statistics & Natural Sciences
 Statistical techniques are proved very useful in
the study of natural sciences. Like: Biology,
medicine, zoology, botany etc.
 Example: In diagnosing the correct disease the
doctor has to rely on data like body
temperature, pulse rate, BP etc.
 Similarly in judging the efficacy of a particular
drug for curing a disease experiments have to
be conducted and the success or failure would
depend upon the number of people who are
cured after using a drug.

Statistics And Research
 Most of the advancement in knowledge has taken
place because of experiments conducted with the
help of Statistical methods.
 Example: Experiments about crop yields &
different types of fertilizers and different types of
soils or the growth of animals under different diets
and environments are designed and analysed with
the help of statistical methods.
 Statistics affect research medicine & public health.
 We can not complete our research work without
statistics.

Limitations of Statistics
 Statistics does not deal with individual
measurements.
 Statistics only deals with Quantitative
Characteristics.
 Statistical results are true only on an
average.
 Statistics is only one of the methods of
studying a problem.
 Statistics can be misused.

Overview of statistics

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