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Anning, depicted with her dog. Mary Anning (21 May 1799 – 9 March 1847) was an English fossil collector and palaeontologist. She made discoveries of Jurassic marine fossil beds in the cliffs along the English Channel at Lyme Regis, which changed the scientific thinking about prehistoric life and the history of the Earth.
Chi-squared distribution, showing χ2 on the x -axis and p -value (right tail probability) on the y -axis. A chi-squared test (also chi-square or χ2 test) is a statistical hypothesis test used in the analysis of contingency tables when the sample sizes are large. In simpler terms, this test is primarily used to examine whether two categorical ...
For instance, consider a call center which receives, randomly, an average of λ = 3 calls per minute at all times of day. If the calls are independent, receiving one does not change the probability of when the next one will arrive. Under these assumptions, the number k of calls received during any minute has a Poisson probability distribution ...
Microcredit is the extension of very small loans ( microloans) to impoverished borrowers who typically lack collateral, steady employment, and a verifiable credit history. It is designed to support entrepreneurship and alleviate poverty. Many recipients are illiterate, and therefore unable to complete paperwork required to get conventional loans.
In medicine and statistics, sensitivity and specificity mathematically describe the accuracy of a test that reports the presence or absence of a medical condition. If individuals who have the condition are considered "positive" and those who do not are considered "negative", then sensitivity is a measure of how well a test can identify true ...
The Navier–Stokes equations ( / nævˈjeɪ stoʊks / nav-YAY STOHKS) are partial differential equations which describe the motion of viscous fluid substances. They were named after French engineer and physicist Claude-Louis Navier and the Irish physicist and mathematician George Gabriel Stokes. They were developed over several decades of ...
This form of the ideal gas law is very useful because it links pressure, density, and temperature in a unique formula independent of the quantity of the considered gas. Alternatively, the law may be written in terms of the specific volume v, the reciprocal of density, as. It is common, especially in engineering and meteorological applications ...
