Gamma distributionIn probability theory and statistics, the gamma distribution is a two-parameter family of continuous probability distributions. The exponential distribution, Erlang distribution, and chi-squared distribution are special cases of the gamma distribution. There are two equivalent parameterizations in common use: With a shape parameter and a scale parameter . With a shape parameter and an inverse scale parameter , called a rate parameter. In each of these forms, both parameters are positive real numbers.
Exponential distributionIn probability theory and statistics, the exponential distribution or negative exponential distribution is the probability distribution of the time between events in a Poisson point process, i.e., a process in which events occur continuously and independently at a constant average rate. It is a particular case of the gamma distribution. It is the continuous analogue of the geometric distribution, and it has the key property of being memoryless. In addition to being used for the analysis of Poisson point processes it is found in various other contexts.
April 1974The following events occurred in April 1974: Born: Håkan Hellström, Swedish musician Died: Douglass Dumbrille, Canadian actor (b. 1889) Georges Pompidou, 100th Prime Minister of France and 19th President of France, Co-Prince of Andorra An enormous tornado outbreak strikes the central parts of the United States, killing around 319 and injuring about 5,484. Born: Died: Carrie, the debut novel by Stephen King, is published. Born: Died: A. Y. Jackson, Canadian painter and a founding member of the Group of Seven (b.
January 9681 – Twelfth Council of Toledo: King Erwig of the Visigoths initiates a council in which he implements diverse measures against the Jews in Spain. 1127 – Jin–Song Wars: Invading Jurchen soldiers from the Jin dynasty besiege and sack Bianjing (Kaifeng), the capital of the Song dynasty of China, and abduct Emperor Qinzong of Song and others, ending the Northern Song dynasty. 1349 – The Jewish population of Basel, believed by the residents to be the cause of the ongoing Black Death, is rounded up and incinerated.
Chi-squared testA 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 variables (two dimensions of the contingency table) are independent in influencing the test statistic (values within the table). The test is valid when the test statistic is chi-squared distributed under the null hypothesis, specifically Pearson's chi-squared test and variants thereof.
Romanian alphabetThe Romanian alphabet is a variant of the Latin alphabet used for writing the Romanian language. It is a modification of the classical Latin alphabet and consists of 31 letters, five of which (Ă, Â, Î, Ș, and Ț) have been modified from their Latin originals for the phonetic requirements of the language: The letters Q (chiu), W (dublu v), and Y (igrec or i grec, meaning "Greek i") were formally introduced in the Romanian alphabet in 1982, although they had been used earlier.
1 − 2 + 3 − 4 + ⋯In mathematics, 1 − 2 + 3 − 4 + ··· is an infinite series whose terms are the successive positive integers, given alternating signs. Using sigma summation notation the sum of the first m terms of the series can be expressed as The infinite series diverges, meaning that its sequence of partial sums, (1, −1, 2, −2, 3, ...), does not tend towards any finite limit. Nonetheless, in the mid-18th century, Leonhard Euler wrote what he admitted to be a paradoxical equation: A rigorous explanation of this equation would not arrive until much later.
Poisson distributionIn probability theory and statistics, the Poisson distribution is a discrete probability distribution that expresses the probability of a given number of events occurring in a fixed interval of time or space if these events occur with a known constant mean rate and independently of the time since the last event. It is named after French mathematician Siméon Denis Poisson ('pwɑːsɒn; pwasɔ̃). The Poisson distribution can also be used for the number of events in other specified interval types such as distance, area, or volume.
Probability distributionIn probability theory and statistics, a probability distribution is the mathematical function that gives the probabilities of occurrence of different possible outcomes for an experiment. It is a mathematical description of a random phenomenon in terms of its sample space and the probabilities of events (subsets of the sample space). For instance, if X is used to denote the outcome of a coin toss ("the experiment"), then the probability distribution of X would take the value 0.5 (1 in 2 or 1/2) for X = heads, and 0.
CircumflexThe circumflex () is a diacritic in the Latin and Greek scripts that is also used in the written forms of many languages and in various romanization and transcription schemes. It received its English name from circumflexus "bent around"a translation of the περισπωμένη (perispōménē). The circumflex in the Latin script is chevron-shaped (), while the Greek circumflex may be displayed either like a tilde () or like an inverted breve (). For the most commonly encountered uses of the accent in the Latin alphabet, precomposed characters are available.
