Cliometrics
Cliometrics (, also ), sometimes called new economic history, or econometric history, is the systematic application of economic theory, econometric techniques, and other formal or mathematical methods to the study of history (especially social and economic history). It is a quantitative (as opposed to qualitative or ethnographic) approach to economic history. The term cliometrics comes from Clio, who was the muse of history, and was originally coined by the mathematical economist Stanley Reiter in 1960. There has been a revival in 'new economic history' since the late 1990s.

History of the discipline
The new economic history originated in 1958 with The Economics of Slavery in the Antebellum South by American economists Alfred H. Conrad and John R. Meyer, which caused a firestorm of controversy with its claim, based on statistical data, that slavery, being economically efficient and highly profitable for slaves owners, would not have ended in the absence of the U.S. Civil War. The new economic history revolution actually began in the mid-1960s and was resisted because many incumbent economic historians were either historians or economists who had very little connection to economic modeling or statistical techniques. Areas of key interest included transportation history, slavery, and agriculture. Cliometrics became better known when Douglass North and William Parker became the editors of the Journal of Economic History in 1960. The Cliometrics Meetings began to be held around this time at Purdue University and are still held annually in different locations. Today, cliometric approaches are standard in several journals, including the Journal of Economic History, Explorations in Economic History, the European Review of Economic History, and Cliometrica.

According to cliometric economist Claudia Goldin, the success of the cliometric revolution had as an unintended consequence the disappearance of economic historians from history departments. As economic historians started using the same tools as economists, they started to seem more like other economists. In Goldin's words, "the new economic historians extinguished the other side". The other side nearly disappeared altogether, with only a few remaining in history departments and business schools.  However, some new economic historians did, in fact, begin research around this time, among them were Kemmerer and Larry Neal (a student of Albert Fishlow, a leader of the cliometric revolution) from Illinois, Paul Uselding from Johns Hopkins, Jeremy Atack from Indiana, and Thomas Ulen from Stanford.

A group to encourage and further the study of cliometrics, The Cliometric Society, was founded in 1983.

Cliometrics was introduced to Germany by American-born and -educated Richard H. Tilly in the 1970s.

There has been a revival in 'new economic history' since the late 1990s. The number of papers on economic history published in the top economics journals has increased in the last decades, comprising 6.6% of articles in the American Economic Review and 10.8% of articles in the Quarterly Journal of Economics for the period 2004-2014.

Nobel Prize in Economics
In October 1993, the Swedish National Bank awarded the Nobel Memorial Prize in Economic Sciences to Robert William Fogel and Douglass Cecil North "for having renewed research in economic history".  The Academy noted that "they were pioneers in the branch of economic history that has been called the 'new economic history,' or cliometrics". Fogel and North received the prize for turning the theoretical and statistical tools of modern economics on the historical past: on subjects ranging from slavery and railroads to ocean shipping and property rights.

Fogel is often described as the father of modern econometric history and Neohistoricals. He's especially noted for using careful empirical work to overturn conventional wisdom.  North, a professor at Washington University in St. Louis, was honored as a pioneer in the "new" institutional history. In the Nobel announcement, specific mention was made of a 1968 paper on ocean shipping, in which North showed that organizational changes played a greater role in increasing productivity than did technological change.

Critics
Cliometrics has had sharp critics. Boldizzoni summarized a common critique by arguing that cliometrics is based on the false assumption that the laws of neo-classical economics always apply to human activity. Those laws, he says, are based on rational choice and maximization as they operate in well-developed markets, and do not apply to economies other than those of the capitalist West in the modern era. Instead, Boldizzoni argues that the workings of economies are determined by social, political and cultural conditions specific to each society and time period.

On the other hand, Diebolt argued that cliometrics is mature and well accepted by scholars as an "indispensable tool" in economic history. He says most scholars agree that economic theory, combined with new data as well as historical and statistical methods are necessary to formulate problems precisely, to draw conclusions from postulates and to gain insight into complicated processes. At the applied level, cliometrics is accepted as the way to measure variables and estimate parameters.

A criticism of Cliometrics by Joseph T. Salerno, based on the perspective of the Austrian School of economics, especially that of Ludwig von Mises, can be found in his Introduction to Murray N. Rothbard's A History of Money and Banking in the United States: The Colonial Era to World War II.

Distinguishing cliometrics and cliodynamics
Cliometrics and cliodynamics share the scientific ambition of using quantitative tools and historical data to test general historical principles. Both fields endeavor to gather large amounts of historical data across big samples. However, the two fields also differ in several important ways. Cliodynamics, unlike cliometrics, maintains a close relationship with the natural sciences, often employing dominant methods from the natural sciences such as differential-equation models, power-law relations, and agent-based models. Evolutionary game theory and social network analysis are also frequently employed by cliodynamicists, but not cliometricians. Cliodynamicists also tend to include factors associated with ecological context and biological determinants in their models.