SOFTWARE/STATA

 

Model testing and post-estimation support

Hypothesis testing

  • Wald test for linear constraints
  • Wald test (delta method) for nonlinear constraints
  • Likelihood-ratio test after any ML estimation
  • Bonferroni, Holm, and Šidák adjustments for multiple comparisons*

Generalized testing

  • ability to combine seperate estimates into single combined estimates
  • robust covariance matrix of combined estimates
  • tests of linear and nonlinear combinations of estimates across estimated models
  • point estimates and confidence intervals of linear and nonlinear combinations of estimates across estimated models

Predictions

  • ability to obtain predicted values after all estimation commands
  • predictor types are tightly coupled to the estimation command

Generalized Predictions

  • linear and nonlinear combinations of
    • standard predictions
    • equation index values
    • estimated coefficients
    • data
  • Inferential statistics for generalized predictions
    • point estimates
    • standard errors
    • variance
    • Wald test statistic
    • significance levels
    • point-wise confidence intervals

Postestimation statistics

  • estimation sample summary statistics*
  • Akaike and Bayesian information criteria*
  • covariance matrix analysis
 

Adjusted predictions

  • predicted values or probabilities
  • predictions adjusted to set levels of regressors
  • predictions adjusted to set levels of covariates
  • predictions adjusted to set levels of terms

Hausman test

  • test the independence of irrelevant alternative (IIA) after
    • multinomial logit
    • conditional logistic regression
  • tests exogeneity or over-identifying restrictions for
    • two-stage least squares (2SLS)
    • three-stage least squares (3SLS)

Point estimates for combinations of coefficients

  • odds ratios
  • standard errors
  • test statistics

Marginal effects

  • marginal effects and elasticities
  • standard errors and confidence intervals
  • computation of effects at means or specified covariate values
  • computation of effects for any predicted statistic

Save and restore estimation results

Nonlinear combinations of coefficients

  • point estimates
  • standard errors
  • t and Z statistics
  • p-values
  • confidence intervals
  • covariances between combinations
  • supports survey and clustered data

* New in Stata 9

© Copyright StataCorp LP 2005.


 
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