Scientific Model Knowledge Base

Curve Fitting Models Library

Comprehensive mathematical formulations, initial guess heuristic algorithms, parameter bounds, and SciPy-verified parity benchmarks for 101 scientific regression models.

Scientific Disciplines

Model Directory

Showing 13 of 13 models
spectroscopy4 params

Gaussian Peak Profile

The fundamental symmetric bell-shaped peak model describing thermal Doppler broadening and instrumental slit resolution.

$y = y_0 + A \exp\left( -\frac{(x - \mu)^2}{2\sigma^2} \right)$
spectroscopy4 params

Lorentzian (Cauchy-Lorentz) Profile

The characteristic heavy-tailed peak profile describing natural radiative lifetime broadening and collisional damping.

$y = y_0 + \frac{2A}{\pi} \frac{\gamma}{4(x - \mu)^2 + \gamma^2}$
spectroscopy5 params

Pseudo-Voigt Profile

A linear combination of Gaussian and Lorentzian functions providing high-speed approximation of Voigt profile line shapes.

$y = y_0 + A \left[ \eta \frac{2}{\pi \gamma} \frac{1}{1 + 4\left(\frac{x - \mu}{\gamma}\right)^2} + (1 - \eta) \frac{2\sqrt{\ln 2}}{\sqrt{\pi} \gamma} \exp\left( -4\ln 2 \left(\frac{x - \mu}{\gamma}\right)^2 \right) \right]$
spectroscopy5 params

True Voigt Profile (Faddeeva Convolution)

The exact physical convolution of Gaussian Doppler broadening and Lorentzian lifetime broadening.

$V(x; \sigma, \gamma) = \int_{-\infty}^{\infty} G(x'; \sigma) L(x - x'; \gamma) \, dx' = \frac{\text{Re}[w(z)]}{\sigma \sqrt{2\pi}}$
spectroscopy5 params

Pearson VII Profile

A versatile continuous peak model bridging pure Gaussian and Lorentzian shapes via a variable exponential exponent (m).

$y = y_0 + A \left[ 1 + 4\left( 2^{1/m} - 1 \right) \left( \frac{x - \mu}{\gamma} \right)^2 \right]^{-m}$
biochemistry4 params

Hill Equation (Dose-Response)

The definitive non-linear model for sigmoidal cooperative binding and pharmacological dose-response relationships.

$y = y_{\min} + \frac{y_{\max} - y_{\min}}{1 + \left(\frac{K}{x}\right)^n} = y_{\min} + (y_{\max} - y_{\min})\frac{x^n}{K^n + x^n}$
biochemistry5 params

5-Parameter Logistic (5PL)

Asymmetric sigmoidal bioassay model incorporating an asymmetry factor (S) for non-symmetric dose-response curves.

$y = D + \frac{A - D}{\left(1 + \left(\frac{x}{C}\right)^B\right)^S}$
biochemistry2 params

Michaelis-Menten Kinetics

The cornerstone hyperbolic kinetic model describing single-substrate enzyme reaction rates.

$v = \frac{V_{\max} [S]}{K_m + [S]}$
kinetics2 params

Arrhenius Equation

The fundamental exponential model relating chemical reaction rate constants and diffusion rates to absolute temperature.

$k(T) = A \exp\left( -\frac{E_a}{R T} \right)$
materials-physics2 params

Weibull Distribution (Cumulative & Density)

The standard continuous probability distribution for brittle fracture strength and component failure lifetime analysis.

$P_f(\sigma) = 1 - \exp\left( -\left(\frac{\sigma}{\sigma_0}\right)^m \right)$
kinetics5 params

Bi-Exponential Decay

Two-phase exponential decay model resolving fast and slow relaxation lifetimes.

$y(t) = y_0 + A_1 \exp\left(-\frac{t}{\tau_1}\right) + A_2 \exp\left(-\frac{t}{\tau_2}\right)$
biochemistry4 params

4-Parameter Logistic (4PL)

The gold-standard symmetric sigmoidal bioassay model for quantitative ELISA and ligand binding calibration.

$y = D + \frac{A - D}{1 + \left(\frac{x}{C}\right)^B}$
engineering-math5 params

Damped Sine Wave (Harmonic Oscillator)

Exponentially decaying sinusoidal oscillation model for transient mechanical vibration and RLC circuit responses.

$y(t) = y_0 + A \exp(-\gamma t) \sin(\omega t + \phi)$

Complete A-Z Model Index

Model NameCategoryMathematical FormulationParametersValidation
Gaussian Peak Profilespectroscopyy = y0 + A * exp(-((x - mu)^2) / (2 * sigma^2))4 (y_0, A, \mu, \sigma)verified
Lorentzian (Cauchy-Lorentz) Profilespectroscopyy = y0 + (2 * A / pi) * (gamma / (4 * (x - mu)^2 + gamma^2))4 (y_0, A, \mu, \gamma)verified
Pseudo-Voigt Profilespectroscopyy = y0 + A * [eta * L(x, mu, gamma) + (1 - eta) * G(x, mu, gamma)]5 (y_0, A, \mu, \gamma, \eta)verified
True Voigt Profile (Faddeeva Convolution)spectroscopyV(x) = Re[wofz(z)] / (sigma * sqrt(2*pi)) where z = (x - mu + i*gamma) / (sigma * sqrt(2))5 (y_0, A, \mu, \sigma, \gamma)verified
Pearson VII Profilespectroscopyy = y0 + A * [1 + 4 * (2^(1/m) - 1) * ((x - mu) / gamma)^2]^(-m)5 (y_0, A, \mu, \gamma, m)verified
Hill Equation (Dose-Response)biochemistryy = ymin + (ymax - ymin) * (x^n) / (K^n + x^n)4 (y_{\min}, y_{\max}, K, n)verified
5-Parameter Logistic (5PL)biochemistryy = D + (A - D) / ((1 + (x / C)^B)^S)5 (A, B, C, D, S)verified
Michaelis-Menten Kineticsbiochemistryv = (Vmax * S) / (Km + S)2 (V_{\max}, K_m)verified
Arrhenius Equationkineticsk = A * exp(-Ea / (R * T))2 (A, E_a)verified
Weibull Distribution (Cumulative & Density)materials-physicsPf = 1 - exp(-(sigma / sigma0)^m)2 (\sigma_0, m)verified
Bi-Exponential Decaykineticsy = y0 + A1 * exp(-t / tau1) + A2 * exp(-t / tau2)5 (y_0, A_1, \tau_1, A_2, \tau_2)verified
4-Parameter Logistic (4PL)biochemistryy = D + (A - D) / (1 + (x / C)^B)4 (A, B, C, D)verified
Damped Sine Wave (Harmonic Oscillator)engineering-mathy = y0 + A * exp(-gamma * t) * sin(omega * t + phi)5 (y_0, A, \gamma, \omega, \phi)verified