logistic curve


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logistic curve

[lə′jis·tik ′kərv]
(statistics)
A type of growth curve, representing the size of a population y as a function of time t : y = k/ (1 + e -kbt ), where k and b are positive constants. Also known as Pearl-Reed curve.
More generally, a curve representing a function of the form y = k/ (1 + e cf (t)), where c is a constant and ƒ(t) is some function of time.
References in periodicals archive ?
The dose-response curve of the calibrator hepcidin-25 was approximated by a 4-parameter logistic curve and showed a dynamic range (SD) of 21 (8) pmol/L to 3.
The logistic curve developed for the relationship followed the actual proportions of individuals that were mature in 13 data bins based on the OL:OW ratio (Fig.
Fitting the logistic curve to data is presented through judicious selection of K (2).
m]))) as a general logistic curve such that the analytical solution for T(t) is given by
The logistic curve in its simplest form is given by the relation:
Logistic regression, used for the prediction of the probability of occurrence of an event by fitting data to a logistic curve, has become one of the most used statistical procedures employed by statisticians and researchers for the analysis of binary and proportional response data, according to Hilbe (emeritus, U.
Logistic regression is the term used to describe the process of fitting a logistic curve to a dataset.
This software solution, which runs on all microplate readers offered by MDS Analytical Technologies, offers significant enhancements over previous releases, including five parameter (5PL) logistic curve fitting; parallel line analysis (PLA) with observation weighting; more than 120 ready-to-run assay protocols for instant results generation; native support for Mac OS X; XML export and multiple-destination AutoSave with new options; enhanced Windows Interprocess Messaging for better robotics/LIMS/SDMS integration; more detailed printed headers and footers; and full backwards-compatibility.
In States which had shown a declining trend, a double logistic curve was fitted and for the remaining States a single logistic curve was fitted.
Using statistical methods to choose the logistic curve that best fits the oil data yields 2014 as the year of peak oil production.
The model parameters are as follows: K is the carrying capacity or total case number, r is the per capita growth rate of the infected population, and a is the exponent of deviation from the standard logistic curve.
For example, it can approximate the logistic curve that has been suggested as a plausible shape for the particulate air pollution concentration-response function (Schwartz and Zanobetti 2000).