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What is Statistics?Even though you may not have realized it, you probably have madesome statistical statements in your everyday conversation or thinking. Statements like "I sleep for about eight hours per night onaverage" and "You are more likely to pass the exam if you startpreparing earlier" are actually statistical in nature.

Statistics is a discipline which is concerned with:

• designing experiments and other data collection,

• summarizing information to aid understanding,

• drawing conclusions from data, and

• estimating the present or predicting the future.

The two statements at the beginning illustrate some of these points.

In making predictions, Statistics uses the companion subject of Probability, which models chance mathematically and enablescalculations of chance in complicated cases.

Today, statistics has become an important tool in the work of manyacademic disciplines such as medicine, psychology, education,

sociology, engineering and physics, just to name a few. Statistics isalso important in many aspects of society such as business, industryand government. Because of the increasing use of statistics in somany areas of our lives, it has become very desirable to understandand practice statistical thinking. This is important even if you do notuse statistical methods directly.

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Abraham de Moivre (26 May 1667 in Vitry-le-

François, Champagne, France – 27 November 

1754 in London, England; French

pronunciation: [abʁam də mwavʁ]) was

a French mathematician famous for de Moivre's 

formula, which links complex 

numbers and trigonometry, and for his work on

the normal distribution and probability theory. He

was a friend of Isaac Newton, Edmund Halley,

and James Stirling. Among his

fellow Huguenot exiles in England, he was a

colleague of the editor and translator Pierre des 

Maizeaux.De Moivre wrote a book on probability theory, The Doctrine of Chances, said to have

been prized by gamblers. De Moivre first discovered Binet's formula, the closed-

form expression for Fibonacci numbers linking the nth power of φ to the nth

Fibonacci number.

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William Sealy Gosset (June 13, 1876–October 16, 1937) is famous as

a statistician, best known by his pen name Student  and for his work on Student's t-

distribution.

Gosset had almost all of his papers including The probable error of a mean published in

Pearson's journal Biometrika using the pseudonym Student . However, it was R. A. 

Fisher who appreciated the importance of Gosset's small-sample work, after Gosset had

written to him to say I am sending you a copy of Student's Tables as you are the only 

man that's ever likely to use them! . Fisher believed that Gosset had effected a “logical

revolution”. Ironically the t -statistic for which Gosset is famous was actually Fisher's

creation. Gosset's statistic was . Fisher introduced the t -form because it

fit in with his theory of degrees of freedom. Fisher was also responsible for the

applications of the t -distribution to regression.

Although introduced by others, Studentized residuals are named in Student's honor 

because, like the problem that led to Student's t-distribution, the idea of adjusting for 

estimated standard deviations is central to that concept.

Gosset's interest in barley cultivation led him to speculate that design of  

experiments should aim, not only at improving the average yield, but also at breeding

varieties whose yield was insensitive (robust) to variation in soil and climate. This

principle only occurs in the later thought of Fisher and then in the work of Genichi 

Taguchi in the 1950s.

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Sir Francis Galton / fr ˈ  ɑːnsɪs gæltnˈ     ̩/ FRS (16 February 1822

 – 17 January 1911), cousin of Douglas Strutt Galton, half-

cousin of  Charles Darwin, was

an English Victorian polymath: anthropologist, eugenicist trop

ical explorer , geographer , inventor ,meteorologist, proto-

geneticist, psychometrician, and statistician. He was knighted

in 1909.

Galton had a prolific intellect, and produced over 340 papers

and books throughout his lifetime. He also created the

statistical concept of  correlation and widely

promoted regression toward the mean. He was the first to

apply statistical methods to the study of human differences

and inheritance of intelligence, and introduced the useof questionnaires and surveys for collecting data on human communities, which he needed for 

genealogical and biographical works and for his anthropometric studies.

He was a pioneer in eugenics, coining the term itself and the phrase "nature versus nurture".

His book, Hereditary Genius (1869), was the first social scientific attempt to

study genius and greatness.[As an investigator of the human mind, he

oundedpsychometrics (the science of measuring mental faculties) and differential psychology.

He devised a method for classifyingfingerprints that proved useful in forensic science. He also

conducted research on the power of prayer , concluding it had none by its null effects on theongevity of those prayed for.

As the initiator of scientific meteorology, he devised the first weather map, proposed a theory

of anticyclones, and was the first to establish a complete record of short-term climatic

phenomena on a European scale. He also invented the Galton Whistle for testing differential

hearing ability.

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Lambert Adolphe Jacques Quetelet (22

February 1796 – 17 February 1874) was

a Belgian astronomer , mathematician,statistician 

and sociologist. He founded and directed the

Brussels Observatory and was influential in

introducing statistical methods to the social 

sciences. His name is sometimes spelled with an

accent as Quételet .

His scientific research encompassed a wide

range of different scientific disciplines:

meteorology, astronomy, mathematics, statistics,

demography, sociology, criminology and history

of science. He made significant contributions toscientific development, but he also wrote several

monographs directed to the general public. He

founded the Royal Observatory of Belgium,

founded or co-founded several national and

nternational statistical societies and scientific journals, and presided over the first series of the

nternational Statistical Congresses. Quetelet was a liberal and an anticlerical, but not an

atheist or materialist nor a socialist.

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Sir Ronald Aylmer Fisher  FRS (17 February 1890

 – 29 July 1962) was an English statistician,

evolutionary biologist, eugenicist and geneticist.Among other things, Fisher is well known for his

contributions to statistics by creating Fisher's exact

test andFisher's equation. Anders Hald called him

"a genius who almost single-handedly created the

foundations for modern statistical

science"[1] while Richard Dawkins called him "the

greatest of Darwin's successors".[2] In 2010

Dawkins named him "the greatest biologist since

Darwin".

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