In statistics, mean has two related meanings:

There are other statistical measures that should not be confused with averages - including 'median' and 'mode'. Other simple statistical analyses use measures of spread, such as range, interquartile range, or standard deviation. For a real-valued random variable X, the mean is the expectation of X. Note that not every probability distribution has a defined mean (or variance); see the Cauchy distribution for an example.

For a data set, the mean is the sum of the values divided by the number of values. The mean of a set of numbers x₁, x₂, ..., x_n is typically denoted by Failed to parse (Missing texvc executable; please see math/README to configure.): \bar{x} , pronounced "x bar". This mean is a type of arithmetic mean. If the data set were based on a series of observations obtained by sampling a statistical population, this mean is termed the "sample mean" (Failed to parse (Missing texvc executable; please see math/README to configure.): \bar{x} ) to distinguish it from the "population mean" (Failed to parse (Missing texvc executable; please see math/README to configure.): \mu or Failed to parse (Missing texvc executable; please see math/README to configure.): \mu _x). The mean is often quoted along with the standard deviation: the mean describes the central location of the data, and the standard deviation describes the spread. An alternative measure of dispersion is the mean deviation, equivalent to the average absolute deviation from the mean. It is less sensitive to outliers, but less mathematically tractable.

Seth Rogen (pronounced /ˈroʊɡɪn/; born April 15, 1982) is a Canadian stand-up comedian, actor, producer, screenwriter, and voice artist. Rogen began his career doing stand-up comedy during his teen years, winning the Vancouver Amateur Comedy Contest in 1998. While still living in his native Vancouver, he landed a small part in Freaks and Geeks. Shortly after Rogen moved to Los Angeles for his role, Freaks and Geeks was canceled after one season due to poor ratings. He then got a part on the equally short-lived Undeclared, which also hired him as a staff writer.

After landing a job as a staff writer on the final season of Da Ali G Show, for which Rogen and the other writers received an Emmy nomination, he was guided by film producer Judd Apatow toward a film career. Rogen was cast in a major supporting role and credited as a co-producer in Apatow's directorial debut, The 40-Year-Old Virgin. After Rogen received critical praise for that performance, Universal Pictures agreed to cast him as the lead in Apatow's directorial feature films Knocked Up and Funny People. Rogen and his comedy partner Evan Goldberg co-wrote the films Superbad, Pineapple Express, and The Green Hornet. Rogen has done voice work for the films Horton Hears a Who!, Kung Fu Panda, Monsters vs. Aliens, and Paul. He married fellow screenwriter Lauren Miller in October 2011.

George Timothy Clooney (born May 6, 1961) is an American actor, film director, producer, and screenwriter. For his work as an actor, he has received three Golden Globe Awards and an Academy Award. Clooney is also noted for his political activism, and has served as one of the United Nations Messengers of Peace since January 31, 2008.

Though he made his acting debut on television in 1978, Clooney gained fame and recognition by portraying Dr. Douglas "Doug" Ross on the long-running medical drama ER from 1994 to 1999. While working on ER, he started attracting a variety of leading roles in films including Batman & Robin (1997) and Out of Sight (1998), in which he first teamed with long-term collaborator Steven Soderbergh. 1999 saw the release of Three Kings, a well-received war satire set during the Gulf War featuring Clooney in another lead role. In 2001, Clooney's fame widened with the release of his biggest commercial success, Ocean's Eleven, the first of a profitable film trilogy, a remake of the film from 1960 with the members of The Rat Pack with Frank Sinatra as Danny Ocean. He made his directorial debut a year later with the 2002 biographical thriller Confessions of a Dangerous Mind, and has since directed Good Night, and Good Luck (2005), Leatherheads (2008), and The Ides of March (2011). He won an Academy Award for Best Supporting Actor for his work in the Middle East thriller Syriana (2005) and subsequently fetched Best Actor nominations for such films as Michael Clayton (2007), Up in the Air (2009) and The Descendants (2011).