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Quetelet received a doctorate in mathematics in 1819 from the University of Ghent. Shortly thereafter, the young man set out to convince government officials and private donors to build an astronomical observatory in Brussels; he succeeded in 1828.
The new science of probability and statistics was mainly used in astronomy at the time, to get a handle on measurement errors with the method of least squaresLeast squares is a mathematical optimization technique that attempts to find a "best fit" to a set of data by attempting to minimize the sum of the squares of the differences (called residuals between the fitted function and the data. It is commonly used. Quetelet was among the first who attempted to apply it to social science, planning what he called a "social physics". He was keenly aware of the overwhelming complexity of social phenomena, and the many variables that needed measurement. His goal was to understand the statistical laws underlying such phenomena as crime rates, marriage rates or suicide rates. He wanted to explain the values of these variables by other social factors. These ideas were rather controversial among other scientists at the time who held that it contradicted a concept of freedom of choice.
His most influential book was Sur l'homme et le développement de se facultés, ou Essai de physique sociale, published in 1835Events January 1 Ole Pedersen Hoiland breaks into the Bank of Norway and steals 64. 000 dalers January 7 HMS Beagle anchors off the Chonos Archipelago. January 30 Unsuccessful assassination attempt against President Andrew Jackson in the United States Cap (In English translation, entitled Treatise on Man). In it, he outlines the project of a social physics and describes his concept of the "average man" (l'homme moyen) who is characterized by the mean values of measured variables that follow a normal distributionProbability density function of Gaussian distribution (bell curve). The normal distribution is an extremely important probability distribution in many fields. It is also called the Gaussian distribution especially in physics and engineering. It is actuall. He collected data about many such variables.
Principal among these, in terms of influence over later public healthPublic Health is an aspect of Health Services concerned with threats to the overall health of the population of a community based on population health analysis. It generally includes infectious disease surveillance and infectious disease control and promo agendas, was Quetelet's establishment of a simple measure for classifying people's weight relative to an ideal weight for their height. His proposal, the Body Mass Index, has endured with minor variations to the present day. It remains the only widely-recognised raw material for obesityObesity is a condition in which the natural energy reserve of a mammal (such as a human), which is stored in fat, is expanded far beyond usual levels to the point where it causes health stress. Obesity in wild animals is relatively rare, but it is common statistics and the policyObesity is a condition in which the natural energy reserve of a mammal (such as a human), which is stored in fat, is expanded far beyond usual levels to the point where it causes health stress. Obesity in wild animals is relatively rare, but it is common discussions related to them.
Quetelet also founded several statistical journals and societies, and was especially interested in creating international cooperation among statisticians.