LogitModelFit
LogitModelFit[{y1,y2,…},{f1,f2,…},x]
constructs a binomial logistic regression model of the form that fits the yi for successive x values 1, 2, ….
LogitModelFit[{{x11,x12,…,y1},{x21,x22,…,y2},…},{f1,…},{x1,x2,…}]
constructs a binomial logistic regression model of the form where the fi depend on the variables xk.
LogitModelFit[{m,v}]
constructs a binomial logistic regression model from the design matrix m and response vector v.
Details and Options

- LogitModelFit returns a symbolic FittedModel object to represent the logistic model it constructs. The properties and diagnostics of the model can be obtained from model["property"].
- The value of the best-fit function from LogitModelFit at a particular point x1, … can be found from model[x1,…].
- With data in the form {{x11,x12,…,y1},{x21,x22,…,y2},…}, the number of coordinates xi1, xi2, … should correspond to the number of variables xi.
- The yi are probabilities between 0 and 1.
- Data in the form {y1,y2,…} is equivalent to data in the form {{1,y1},{2,y2},…}.
- LogitModelFit produces a logistic model of the form
under the assumption that the original
are independent observations following binomial distributions with mean
.
- In LogitModelFit[{m,v}], the design matrix m is formed from the values of basis functions fi at data points in the form {{f1,f2,…},{f1,f2,…},…}. The response vector v is the list of responses {y1,y2,…}.
- For a design matrix m and response vector v, the model is
, where
is the vector of parameters to be estimated.
- When a design matrix is used, the basis functions fi can be specified using the form LogitModelFit[{m,v},{f1,f2,…}].
- LogitModelFit is equivalent to GeneralizedLinearModelFit with ExponentialFamily->"Binomial" and LinkFunction->Automatic.
- LogitModelFit takes the same options as GeneralizedLinearModelFit, with the exception of ExponentialFamily and LinkFunction.
Examples
open allclose allBasic Examples (1)
Scope (10)
Fit data with success probability responses:
Weight by the number of observations for each predictor value:
This gives the same best-fit function as success-failure data:
Fit a model given a design matrix and response vector:
Fit the model referring to the basis functions as x and y:
Obtain a list of available properties:
Properties (7)
Data & Fitted Functions (1)
Residuals (1)
Dispersion and Deviances (1)
Fit a logit model to some data:
The estimated dispersion is 1 by default:
Use Pearson's as the dispersion estimator instead:
Plot the deviances for each point:
Obtain the analysis of deviance table:
Get the residual deviances from the table:
Extract the numeric entries from the table:
Use Grid to add formatting:
Parameter Estimation Diagnostics (1)
Influence Measures (1)
Generalizations & Extensions (1)
Options (8)
ConfidenceLevel (1)
The default gives 95% confidence intervals:
Set the level to 90% within FittedModel:
CovarianceEstimatorFunction (1)
DispersionEstimatorFunction (1)
LinearOffsetFunction (1)
Fit data to a model with a known Sqrt[x] term:
NominalVariables (1)
WorkingPrecision (1)
Use WorkingPrecision to get higher precision in parameter estimates:
Reduce the precision in property computations after the fitting:
Properties & Relations (4)
A default "Binomial" model from GeneralizedLinearModelFit is equivalent to the model for LogitModelFit:
ProbitModelFit is equivalent to a "Binomial" model with "ProbitLink":
LogitModelFit assumes binomially distributed responses:
NonlinearModelFit assumes normally distributed responses:
LogitModelFit will use the time stamps of a TimeSeries as variables:
Rescale the time stamps and fit again:
LogitModelFit acts pathwise on a multipath TemporalData:
Text
Wolfram Research (2008), LogitModelFit, Wolfram Language function, https://reference.wolfram.com/language/ref/LogitModelFit.html.
CMS
Wolfram Language. 2008. "LogitModelFit." Wolfram Language & System Documentation Center. Wolfram Research. https://reference.wolfram.com/language/ref/LogitModelFit.html.
APA
Wolfram Language. (2008). LogitModelFit. Wolfram Language & System Documentation Center. Retrieved from https://reference.wolfram.com/language/ref/LogitModelFit.html