- noun a fixed limit
- noun a set of measurable values such as temperature which define a system and determine its behaviour
- noun an item of information which defines the limits or actions of something, e.g. a variable, routine or program
- For a given system, one of multiple factors or variables, such as temperature or current, which help determine and quantify its behavior.
- A specific value for a circuit component, such as the resistance of a resistor, or the capacitance of a capacitor, in a given circuit configuration. Also called circuit parameter.
- A quantity which can be assigned an arbitrary value for one set of specific conditions, and another for others.
- A value or expression that is passed between functions or programs for processing. This information is used to carry out operations. For instance, in the logarithmic function log (x), the argument is x. Also called argument.
- (written as Parameter)
Parameters do not relate to the actual measurements or attributes of a variable but are quantities that define a theoretical model. The coefficients on the input variables in a production function are parameters. The mean and standard deviation of a theoretical distribution that might be used to characterize an empirical distribution are likewise parameters, as are the height and slope of a regression line (the regression coefficients) parameters of the regression model.
Parameters can also be values that are altered to see what happens in a model or a system. For example, the construction of a partial equilibrium demand curve normally assumes constant real income but it is often interesting to ask what happens if real income changes. In doing this one is effectively treating real income as a parameter rather than a value in an observed dataset. The cost-effectiveness of a screening programme will depend, amongst other things, on the sensitivity ands pecificity of the screening test. In assuming different values for them in order to discover the consequences for cost-effectiveness, one is treating them parametrically. The term 'parameter' is often misused by, for example, being confused with variable, or, even more vulgarly, with 'perimeter', as in the degraded English phrase 'within these parameters'.
Information & Library Science
- noun a limit which affects how something is done or made
- noun a measurement of something such as blood pressure which may be an important consideration in treating the condition which the person has