A BRIEF HISTORY A BRIEF HISTORY OF STATISTICSOF STATISTICS

Miss Donna Marie B. Miss Donna Marie B. de Mesade Mesa

Early Civilization HistoryEarly Civilization History

Simple forms of statistics have been used since the beginning of civilization, when pictorial representations or other symbols were used to record numbers of people, animals, and inanimate objects on skins, slabs, or sticks of wood and the walls of caves.

Early Civilization HistoryEarly Civilization History

Before 3000 bc the Babylonians used Babylonians used small clay tablets to record small clay tablets to record tabulations of agricultural yields and tabulations of agricultural yields and of commodities bartered or soldof commodities bartered or sold.

The Egyptians analyzed the Egyptians analyzed the population and material wealth of their population and material wealth of their countrycountry before beginning to build the pyramids in the 31st century bc.

Early Civilization HistoryEarly Civilization HistoryThe biblical books are primarily biblical books are primarily

statistical worksstatistical worksNumbers - Numbers - containing two separate

censuses of the Israelites Chronicles -Chronicles - describing the

material wealth of various Jewish tribes.

Early Civilization HistoryEarly Civilization HistorySimilar numerical records

existed in China before 2000 bc.

The ancient Greeks held ancient Greeks held censuses to be used as bases censuses to be used as bases for taxationfor taxation as early as 594 bc594 bc.

Early Civilization HistoryEarly Civilization History

Roman Empire - first government Roman Empire - first government to gather extensive data about to gather extensive data about the population, area, and wealth the population, area, and wealth of the territories that it controlledof the territories that it controlled.

Europe few comprehensive Europe few comprehensive censuses were made (censuses were made (Middle Ages).

Early Civilization HistoryEarly Civilization History

The Carolingian kings Carolingian kings ordered surveys of ordered surveys of ecclesiastical holdings: ecclesiastical holdings: Pepin the Short - Pepin the Short - 758Charlemagne Charlemagne - 762

Early Civilization HistoryEarly Civilization History

Following the Norman Conquest of England in 1066, William I, king of England, ordered a census to be taken; the information gathered in this census, conducted in 1086, was recorded in the Domesday BookDomesday Book.

Early Civilization HistoryEarly Civilization History

Registration of deaths and Registration of deaths and births was begun in England in births was begun in England in the early 16th centurythe early 16th century

1662 the first noteworthy 1662 the first noteworthy statistical study of populationstatistical study of population, Observations on the London Bills of MortalityBills of Mortality was written.

Early Civilization HistoryEarly Civilization History

A similar study of mortalitystudy of mortality made in Breslau, Germany, in 1691 was used by the English astronomer Edmond English astronomer Edmond HalleyHalley as a basis for the earliest mortality table.

HistoryHistoryA systematic collection of

data on the population and the economy was begun in the Italian city states of Venice and Florence during the Renaissance.

HistoryHistoryThe term statistics, derived from the word state, was used to refer to a collection of facts of interest to the state.

HistoryHistoryThe idea of collecting data

spread from Italy to the other countries of Western Europe.

by the first half of the 16th century it was common for European governments to require parishes to register births, marriages, and deaths.

HistoryHistoryBecause of poor public health

conditions this last statistic was of particular interest

high mortality rate in Europe before the 19th century was due mainly to epidemic diseases, wars, and famines.

HistoryHistoryAmong epidemics, the worst

were the plagues.

Starting with the Black Plague in 1348, plagues recurred frequently for nearly 400 years.

PlaguePlagueepidemic diseasea disease that spreads

rapidly through a population, killing a great many people, or an outbreak of such a disease

HistoryHistoryIn 1562, as a way to alert the King’s

court to consider moving to the countryside, the City of London began to publish weekly bills of mortality.

Initially these mortality bills listed the places of death and whether a death had resulted from plague. Beginning in 1625 the bills were expanded to include all causes of death.

HistoryHistoryIn 1662 the English tradesman John

Graunt published a book entitled Natural and Political Observations Made upon the Bills of Mortality.

Table 1.1, which notes the total number of deaths in England and the number due to the plague for five different plague, is taken from this book.

HistoryHistoryGraunt used London bills of mortality Graunt used London bills of mortality

to estimate the city’s populationto estimate the city’s population.

For instance, to estimate the population of London in 1660, Graunt surveyed households in certain London parishes (or neighborhoods) and discovered that, on average, there were approx. 3 deaths for every 88 people.

HistoryHistoryDividing by 3 shows that, on average,

there was roughly 1 death for every 88/3 people. Because the London bills cited 13,200 deaths in London for that year

Graunt estimated the London population to be about

13,200 × 88/3 = 387,200

HistoryHistoryGraunt used this estimate to

project a figure for all England. In his book he noted that these

figures would be of interest to the rulers of the country, as indicators of both the number of men who could be drafted into an armydrafted into an army and the number who could be taxedcould be taxed.

HistoryHistoryGraunt also used the London bills

of mortality—and some intelligent guesswork as to what diseases killed whom and at what age — to infer ages at death.

(Recall that the bills of mortality listed only causes and places at death, not the ages of those dying.)

HistoryHistoryGraunt then used this information to

compute tables giving the proportion of the population that dies at various ages. Table 1.2 is one of Graunt’s mortality tables.

It states, for instance, that of 100 births, 36 people will die before reaching age 6, 24 will die between the age of 6 and 15, and so on.

HistoryHistoryGraunt’s estimates of the ages at

which people were dying were of people were dying were of great interest to those in the business great interest to those in the business of selling annuitiesof selling annuities.

Annuities Annuities -- opposite of life insuranceopposite of life insurance in that one pays in a lump sum as an investment and then receives regular payments for as long as one lives.

HistoryHistoryGraunt’s work on mortality tables

inspired further work by Edmund Edmund Halley in 1693Halley in 1693.

HalleyHalley, the discoverer of the comet bearing his name (and also the man who was most responsible, by both his encouragement and his financial support,

HistoryHistory for the publication of Isaac Newton’s

famous Principia Mathematica), used used tables of mortality to compute the odds tables of mortality to compute the odds that a person of any age would live to that a person of any age would live to any other particular ageany other particular age.

Halley was influential in convincing the insurers of the time that an annual life insurance premium should depend on the age of the person being insured.

HistoryHistoryFollowing Graunt and Halley, the

collection of data steadily increased collection of data steadily increased throughout the remainder of the 17th throughout the remainder of the 17th and on into the 18th centuryand on into the 18th century.

the city of Paris began collecting bills of mortality in 1667

1730 it had become common practice throughout Europe to record ages at death

HistoryHistoryThe term statisticsstatistics, which was used

until the 18th century as a shorthand for the descriptive science of states

19th century statisticsstatistics increasingly identified with numbers.

By the 1830s the term was almost universally regarded in Britain and France as being synonymous with the “numerical science” of society.

HistoryHistoryThis change in meaning was change in meaning was

caused by the large availability of caused by the large availability of census records and other census records and other tabulations that began to be tabulations that began to be systematically collected and systematically collected and published by the governmentspublished by the governments of Western Europe and the United States beginning around 1800.

HistoryHistoryThroughout the 19th century,

although probability theory had been developed by such mathematicians: Jacob BernoulliKarl Friedrich GaussPierre-Simon Laplace

- its use in studying statistical findings was its use in studying statistical findings was almost nonexistent, because most social almost nonexistent, because most social statisticians at the time were content to let the statisticians at the time were content to let the data speak for themselves.data speak for themselves.

HistoryHistorystatisticians of that time were not statisticians of that time were not

interested in drawing inferences interested in drawing inferences about individualsabout individuals, - concerned with the society as a whole.

they were not concerned with sampling but rather tried to obtain censuses of the entire population.

HistoryHistoryprobabilistic inference from samples to a population was almost unknown in 19th century social statistics.

HistoryHistoryuntil the late 1800s that statistics became concerned with inferring conclusions from numerical data.

The movement began with Francis Galton’s work on analyzing hereditary analyzing hereditary genius through the uses of what we genius through the uses of what we would now call regression and would now call regression and correlation analysiscorrelation analysis and obtained much of its impetus from the work of Karl Pearson.

HistoryHistoryPearsonPearson, who developed the chi-

square goodness of fit tests , was the first director of the Galton Laboratory, endowed by Francis Galton in 1904.

Pearson Pearson originated a research program aimed at developing new methods of using statistics in inference.

HistoryHistoryHis laboratory invited advanced

students from science and industry to learn statistical methods that could then be applied in their fields.

One of his earliest visiting researchers was W. S. Gosset, a chemist by training, who showed his devotion to Pearson by publishing his own works under the name “Student.”

Story behind…Story behind…A famous story has it that Gosset was A famous story has it that Gosset was

afraid to publish under his own name afraid to publish under his own name for fear that his employers, the for fear that his employers, the Guinness brewery, would be unhappy Guinness brewery, would be unhappy to discover that one of its chemists to discover that one of its chemists was doing research in statistics.was doing research in statistics.

Gosset is famous for his Gosset is famous for his development of the t-testdevelopment of the t-test

HistoryHistoryTwo of the most important areas of

applied statistics in the early 20th: population biology agriculture.

This was due to the interest of Pearson and others at his laboratory and also to the remarkable accomplishments of the English scientist Ronald A. Fisher.

HistoryHistoryThe theory of inference developed by

these pioneers, including among others: Karl Pearson’s son Egon Polish born mathematical

statistician Jerzy Neyman- was general enough to deal with a wide range of quantitative and practical problems.

HistoryHistoryafter the early years of the 20th

century a rapidly increasing number of people in science, business, and government began to regard statistics as a tool that was able to provide quantitative solutions to scientific and practical problems

HistoryHistoryNowadays the ideas of

statistics are everywhere.

Descriptive statisticsDescriptive statistics

are featured in every newspaper and magazine.

HistoryHistoryStatistical inference has become

indispensable to: public health and medical researchengineering and scientific studiesmarketing and quality controlEducationaccountingEconomics

HistoryHistoryStatistical inference has become

indispensable to:meteorological forecastingpolling and surveysSportsInsuranceGamblingresearch that makes any claim to being

scientific.

HistoryHistoryStatistics has indeed become ingrained in our intellectual heritage.

The Changing Definition The Changing Definition of Statisticsof StatisticsStatistics has then for its object that of presenting a faithful representation of a state at a determined epoch. (Quetelet, 1849)

The Changing Definition The Changing Definition of Statisticsof StatisticsStatistics are the only tools

by which an opening can be cut through the formidable thicket of difficulties that bars the path of those who pursue the Science of man. (Galton, 1889)

The Changing Definition The Changing Definition of Statisticsof StatisticsStatistics may be regarded (i)

as the study of populations, (ii) as the study of variation, and (iii) as the study of methods of the reduction of data. (Fisher, 1925)

The Changing Definition The Changing Definition of Statisticsof Statistics

Statistics is a scientific discipline concerned with collection, analysis, and interpretation of data obtained from observation or experiment.

The subject has a coherent structure based on the theory of Probability and includes many different procedures which contribute to research and development throughout the whole of Science and Technology. (E. Pearson, 1936)

The Changing Definition The Changing Definition of Statisticsof StatisticsStatistics is the name for that

science and art which deals with uncertain inferences — which uses

numbers to find out something about nature and experience. (Weaver, 1952)

The Changing Definition The Changing Definition of Statisticsof StatisticsStatistics has become

known in the 20th century as the mathematical tool for analyzing experimental and observational data. (Porter, 1986)

The Changing Definition The Changing Definition of Statisticsof StatisticsStatistics is the art of learning from data. (Ross, “Intro. to Probability & Statistics, 2004)

Persons behind StatisticsPersons behind StatisticsThomas BayesThomas Bayes

- formulated a theorem that relates the probability of particular events taking place to the probability that events conditional upon them have occurred.

For example, the probability of picking an ace at random out of a pack of cards is 4/52.

Persons behind StatisticsPersons behind StatisticsPierre Simon de LaplacePierre Simon de Laplace - He also worked on the theory of

probabilities in his Théorie analytique des probabilités (Analytical Theory of Probabilities, 1812) and Philosophical Essay on Probabilities (1814; trans. 1905).

Persons behind StatisticsPersons behind Statistics Carl Friedrich GaussCarl Friedrich Gauss

- In probability theory, he developed the important method of least squares and the fundamental laws of probability distribution

- The normal probability graph is still called the Gaussian curve.

Persons behind StatisticsPersons behind StatisticsAdolphe QuételetAdolphe Quételet - (1830s) Belgian statistician attempted to

make racial classification into a mathematical science.

- He suggested that within human populations, many traits, when plotted on a graph, could be shown to fall into what is known as a bell curve or normal distributionbell curve or normal distribution

Persons behind StatisticsPersons behind StatisticsRonald FisherRonald Fisher (1890-1962)

- British statistician and geneticist, whose statistical theories made scientific experimentation far more precise.

- Fisher showed that by partitioning the variations of a body of data, one can accurately assess how they influence one another and the outcome of the experiment.

Persons behind StatisticsPersons behind StatisticsChristian HuygensChristian Huygens - An unpublished piece by

Pascal on gambling stimulated Dutch scientist Christiaan Huygens to publish a small work in 1657 on probabilities in dice games

Persons behind StatisticsPersons behind Statistics Blaise Pascal & Blaise Pascal & Pierre Pierre de Fermatde Fermat

French Mathematicians Propose the Theory of Probability (1654)

becomes important in theoretical physics and in such fields as actuarial, mathematical, and social statistics.

Persons behind StatisticsPersons behind StatisticsBlaise PascalBlaise Pascal - in conjunction with the French

mathematician Pierre de Fermat, Pascal formulated the mathematical theory of probability, which has become important in such fields as actuarial, mathematical, and social statistics and as a fundamental element in the calculations of modern theoretical physics.