help logistic dialogs: logistic svy: logistic
also see: logistic postestimation
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Title
[R] logistic -- Logistic regression, reporting odds ratios
Syntax
logistic depvar indepvars [if] [in] [weight] [, options]
options description
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Model
offset(varname) include varname in model with coefficient
constrained to 1
asis retain perfect predictor variables
constraints(constraints) apply specified linear constraints
collinear keep collinear variables
SE/Robust
vce(vcetype) vcetype may be oim, robust, cluster
clustvar, bootstrap, or jackknife
Reporting
level(#) set confidence level; default is level(95)
coef report estimated coefficients
nocnsreport do not display constraints
display_options control spacing and display of omitted
variables and base and empty cells
Maximization
maximize_options control the maximization process; seldom
used
+ coeflegend display coefficients' legend instead of
coefficient table
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+ coeflegend does not appear in the dialog box.
indepvars may contain factor variables; see fvvarlist.
depvar and indepvars may contain time-series operators; see tsvarlist.
bootstrap, by, fracpoly, jackknife, mfp, mi estimate, nestreg, rolling,
statsby, stepwise, and svy are allowed; see prefix.
vce(bootstrap) and vce(jackknife) are not allowed with the mi estimate
prefix.
Weights are not allowed with the bootstrap prefix.
vce() and weights are not allowed with the svy prefix.
fweights, iweights, and pweights are allowed; see weight.
See [R] logistic postestimation for features available after estimation.
Menu
Statistics > Binary outcomes > Logistic regression (reporting odds
ratios)
Description
logistic fits a logistic regression model of depvar on varlist, where
depvar is a 0/1 variable (or, more precisely, a 0/non-0 variable).
Without arguments, logistic redisplays the last logistic estimates.
logistic displays estimates as odds ratios; to view coefficients, type
logit after running logistic. To obtain odds ratios for any covariate
pattern relative to another, see [R] lincom.
See logistic estimation commands for a list of related estimation
commands.
Options
+-------+
----+ Model +------------------------------------------------------------
offset(varname), constraints(constraints), collinear; see [R] estimation
options.
asis forces retention of perfect predictor variables and their associated
perfectly predicted observations and may produce instabilities in
maximization; see [R] probit.
+-----------+
----+ SE/Robust +--------------------------------------------------------
vce(vcetype) specifies the type of standard error reported, which
includes types that are derived from asymptotic theory, that are
robust to some kinds of misspecification, that allow for intragroup
correlation, and that use bootstrap or jackknife methods; see [R]
vce_option.
+-----------+
----+ Reporting +--------------------------------------------------------
level(#); see [R] estimation options.
coef causes logistic to report the estimated coefficients rather than the
odds ratios (exponentiated coefficients). coef may be specified when
the model is fit or may be used later to redisplay results. coef
affects only how results are displayed and not how they are
estimated.
nocnsreport; see [R] estimation options.
display_options: noomitted, vsquish, noemptycells, baselevels,
allbaselevels; see [R] estimation options.
+--------------+
----+ Maximization +-----------------------------------------------------
maximize_options: difficult, technique(algorithm_spec), iterate(#),
[no]log, trace, gradient, showstep, hessian, showtolerance,
tolerance(#), ltolerance(#), nrtolerance(#), nonrtolerance,
from(init_specs); see [R] maximize. These options are seldom used.
The following option is available with logistic but is not shown in the
dialog box:
coeflegend; see [R] estimation options.
Examples
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Setup
. webuse lbw
Logistic regression
. logistic low age lwt i.race smoke ptl ht ui
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Setup
. webuse nhanes2d
. svyset
Logistic regression using survey data
. svy: logistic highbp height weight age female
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Saved results
logistic saves the following in e():
Scalars
e(N) number of observations
e(N_cds) number of completely determined successes
e(N_cdf) number of completely determined failures
e(k) number of parameters
e(k_eq) number of equations in e(b)
e(k_eq_model) number of equations in model Wald test
e(k_dv) number of dependent variables
e(k_autoCns) number of base, empty, and omitted constraints
e(df_m) model degrees of freedom
e(r2_p) pseudo-R-squared
e(ll) log likelihood
e(ll_0) log likelihood, constant-only model
e(N_clust) number of clusters
e(chi2) chi-squared
e(p) significance
e(rank) rank of e(V)
e(ic) number of iterations
e(rc) return code
e(converged) 1 if converged, 0 otherwise
Macros
e(cmd) logit
e(cmdline) command as typed
e(depvar) name of dependent variable
e(wtype) weight type
e(wexp) weight expression
e(title) title in estimation output
e(clustvar) name of cluster variable
e(offset) offset
e(chi2type) Wald or LR; type of model chi-squared test
e(vce) vcetype specified in vce()
e(vcetype) title used to label Std. Err.
e(opt) type of optimization
e(which) max or min; whether optimizer is to perform
maximization or minimization
e(ml_method) type of ml method
e(user) name of likelihood-evaluator program
e(technique) maximization technique
e(singularHmethod) m-marquardt or hybrid; method used when Hessian is
singular
e(crittype) optimization criterion
e(properties) b V
e(estat_cmd) program used to implement estat
e(predict) program used to implement predict
e(marginsnotok) predictions disallowed by margins
e(asbalanced) factor variables fvset as asbalanced
e(asobserved) factor variables fvset as asobserved
Matrices
e(b) coefficient vector
e(Cns) constraints matrix
e(ilog) iteration log (up to 20 iterations)
e(gradient) gradient vector
e(mns) vector of means of the independent variables
e(rules) information about perfect predictors
e(V) variance-covariance matrix of the estimators
e(V_modelbased) model-based variance
Functions
e(sample) marks estimation sample
Also see
Manual: [R] logistic
Help: [R] logistic postestimation;
[R] brier, [R] exlogistic, [R] logit, [R] roctab, [SVY] svy
estimation, [XT] xtlogit
