68–95–99.7 rule

In statistics, the so-called 68–95–99.7 rule is a shorthand used to remember the percentage of values that lie within a band around the mean in a normal distribution with a width of one, two and three standard deviations, respectively; more accurately, 68.27%, 95.45% and 99.73% of the values lie within one, two and three standard deviations of the mean, respectively. In mathematical notation, these facts can be expressed as follows, where x is an observation from a normally distributed random variable, μ is the mean of the distribution, and σ is its standard deviation:

In the empirical sciences the so-called three-sigma rule of thumb expresses a conventional heuristic that "nearly all" values are taken to lie within three standard deviations of the mean, i.e. that it is empirically useful to treat 99.7% probability as "near certainty". The usefulness of this heuristic of course depends significantly on the question under consideration, and there are other conventions, e.g. in the social sciences a result may be considered "significant" if its confidence level is of the order of a two-sigma effect (95%), while in particle physics, there is a convention of a five-sigma effect (99.99994% confidence) being required to qualify as a "discovery".

Sigma Seven

Sigma Seven Co., Ltd. (株式会社シグマ・セブン, Kabushiki-gaisha Shiguma Sebun) is a Japanese talent management firm representing a fair number of voice actors and entertainers. Founded on March 3, 1988, Sigma Seven is headquartered on the third floor of the Haga Building in Minato, Tokyo, Japan.

Notable voice actors

Female

Male

References

External links

Sigma factor

A sigma factor (σ factor) is a protein needed only for initiation of RNA synthesis. It is a bacterial transcription initiation factor that enables specific binding of RNA polymerase to gene promoters. The specific sigma factor used to initiate transcription of a given gene will vary, depending on the gene and on the environmental signals needed to initiate transcription of that gene.

Every molecule of RNA polymerase holoenzyme contains exactly one sigma factor subunit, which in the model bacterium Escherichia coli is one of those listed below. The number of sigma factors varies between bacterial species.E. coli has seven sigma factors. Sigma factors are distinguished by their characteristic molecular weights. For example, σ⁷⁰ refers to the sigma factor with a molecular weight of 70 kDa.

RNA polymerase holoenzyme complex consisting of core RNA polymerase and a sigma factor executes transcription of a DNA template strand. Once initiation of RNA transcription is complete, the sigma factor can leave the complex.

Sign

A sign is an object, quality, event, or entity whose presence or occurrence indicates the probable presence or occurrence of something else. A natural sign bears a causal relation to its object—for instance, thunder is a sign of storm, or medical symptoms signify a disease. A conventional sign signifies by agreement, as a full stop signifies the end of a sentence; similarly the words and expressions of a language, as well as bodily gestures, can be regarded as signs, expressing particular meanings. The physical objects most commonly referred to as signs (notices, road signs, etc., collectively known as signage) generally inform or instruct using written text, symbols, pictures or a combination of these.

The philosophical study of signs and symbols is called semiotics; this includes the study of semiosis, which is the way in which signs (in the semiotic sense) operate.

Nature

Ampersand

The ampersand is the logogram "&", representing the conjunction word "and". It originated as a ligature of the letters et, Latin for "and".

Etymology

The word ampersand is a corruption of the phrase "and per se & (and)", meaning "and intrinsically the word and (represented by the symbol &)".

Traditionally, when reciting the alphabet in English-speaking schools, any letter that could also be used as a word in itself ("A", "I", and, at one point, "O") was repeated with the Latin expression per se ("by itself"). This habit was useful in spelling where a word or syllable was repeated after spelling; e.g. "d, o, g—dog" would be clear but simply saying "a—a" would be confusing without the clarifying "per se" added. It was also common practice to add the "&" sign at the end of the alphabet as if it were the 27th letter, pronounced as the Latin et or later in English as and. As a result, the recitation of the alphabet would end in "X, Y, Z, and per se and". This last phrase was routinely slurred to "ampersand" and the term had entered common English usage by 1837. However, in contrast to the 26 letters, the ampersand does not represent a speech sound—although other characters that were dropped from the English alphabet did, such as the Old English thorn, wynn, and eth.

Sign (album)

Sign is the seventh album by Clock DVA, released on August 3, 1993 through Contempo Records.

Track listing

All songs written and composed by Robert Baker and Adi Newton. 

Personnel

References

External links