parameter

parameter
—parametric /par'euh me"trik/, parametrical, adj.
/peuh ram"i teuhr/, n.
1. Math.
a. a constant or variable term in a function that determines the specific form of the function but not its general nature, as a in f(x) = ax, where a determines only the slope of the line described by f(x).
b. one of the independent variables in a set of parametric equations.
2. Statistics. a variable entering into the mathematical form of any distribution such that the possible values of the variable correspond to different distributions.
3. Computers. a variable that must be given a specific value during the execution of a program or of a procedure within a program.
4. Usually, parameters. limits or boundaries; guidelines: the basic parameters of our foreign policy.
5. characteristic or factor; aspect; element: a useful parameter for judging long-term success.
[1650-60; < NL parametrum. See PARA-1, -METER]
Usage. 4, 5. Some object strongly to the use of PARAMETER in these newer senses. Nevertheless, the criticized uses are now well established both in educated speech and in edited writing.

* * *

▪ mathematics and statistics
      in mathematics, a variable for which the range of possible values identifies a collection of distinct cases in a problem. Any equation expressed in terms of parameters is a parametric equation. The general equation of a straight line in slope-intercept form, y = mx + b, in which m and b are parameters, is an example of a parametric equation. When values are assigned to the parameters, such as the slope m = 2 and the y-intercept b = 3, and substitution is made, the resulting equation, y = 2x + 3, is that of a specific straight line and is no longer parametric.

      In the set of equations x = 2t + 1 and y = t2 + 2, t is called the parameter. As the parameter varies over a given domain of values, the set of solutions, or points (x, y), describes a curve in the plane. The use of parameters often enables descriptions of very simple curves for which it is difficult to write down a single equation in x and y.

      In statistics, the parameter in a function is a variable whose value is sought by means of evidence from samples. The resulting assigned value is the estimate, or statistic.

* * *


Universalium. 2010.

Игры ⚽ Нужен реферат?

Look at other dictionaries:

  • Parameter — Parameter, im allgemeinen jede Größe, die in einer Funktion neben den. Veränderlichen enthalten ist. Bei einem Kegelschnitt (s.d.) ist der Parameter die Länge der im Brennpunkt auf der Hauptachse senkrechten Sehne. Der Halbparameter ist der… …   Lexikon der gesamten Technik

  • parameter — In technical use, a parameter is a measurable factor that contributes to determining a system or event. In the 20c it developed rapidly into the kind of word that Fowler (1926) described as a ‘popularized technicality’, many instances of which he …   Modern English usage

  • Parameter — Pa*ram e*ter, n. [Pref. para + meter: cf. F. param[ e]tre.] 1. A constant number which is part of a theory, function, or calculation, whose value is not determined by the form of the theory or equation itself, and may in some cases be arbitrary… …   The Collaborative International Dictionary of English

  • parameter — (n.) 1650s, from Mod.L. parameter (1630s), from Gk. para beside, subsidiary + metron measure (see METER (Cf. meter) (n.2)). A geometry term until 1920s when it yielded sense of measurable factor which helps to define a particular system (1927).… …   Etymology dictionary

  • Paramĕter — (gr.), jede Constante, welche in der Gleichung einer geraden Linie vorkommt. P. einer Parabel, die durch den Brennpunkt der Parabel gelegte, auf der Achse senkrecht stehende Sehne. Ist also y2 = px die Scheitelgleichung der Parabel für… …   Pierer's Universal-Lexikon

  • Parameter — (griech., Nebenmaß) einer Funktion, Gleichung, Kurve oder Fläche heißt jede unbestimmte Konstante, von der die Funktion etc. abhängt und durch deren verschiedene Wahl sich die Gestalt der Funktion etc. ändert. Über P. bei den Kegelschnitten s. d …   Meyers Großes Konversations-Lexikon

  • Parameter — Paramĕter (grch.), jede in der Gleichung einer Kurve vorkommende Konstante; bei einem Kegelschnitt die durch den Brennpunkt gehende, auf der Hauptachse senkrechte Sehne …   Kleines Konversations-Lexikon

  • Parameter — Parameter, in der Geometrie doppelte Ordinate, die durch den Brennpunkt eines Kegelschnitts geht. Vergl. Ellipse, Hyperbel, Parabel …   Herders Conversations-Lexikon

  • parameter — index guideline Burton s Legal Thesaurus. William C. Burton. 2006 …   Law dictionary

  • Parameter — (matematik), når man i analytisk geometri lader nogle af konstanterne i ligningen for en kurve eller flade efterhånden antager alle mulige værider, vil ligningen komme til at fremstille uendelig mange kurver eller flader med visse fælles… …   Danske encyklopædi

  • parameter — [n] limit constant, criterion, framework, guideline, limitation, restriction, specification; concept 688 …   New thesaurus

Share the article and excerpts

Direct link
… Do a right-click on the link above
and select “Copy Link”