CNTSELECT Procedure

PROC CNTSELECT Features

The CNTSELECT procedure estimates the parameters of a count regression model by using maximum likelihood or Bayesian techniques.

The CNTSELECT procedure supports the following models for count data:

  • Poisson regression

  • Conway-Maxwell-Poisson regression

  • negative binomial regression with quadratic and linear variance functions (Cameron and Trivedi 1986)

  • zero-inflated Poisson (ZIP) model (Lambert 1992)

  • zero-inflated Conway-Maxwell-Poisson (ZICMP) model

  • zero-inflated negative binomial (ZINB) model

  • fixed-effects and random-effects Poisson models for panel data

  • fixed-effects and random-effects negative binomial models for panel data

The following list summarizes some basic features of the CNTSELECT procedure:

  • has model-building syntax that uses CLASS and effect-based MODEL statements familiar from SAS/Econometrics analytic procedures

  • performs maximum likelihood estimation

  • supports multiple link functions

  • uses the WEIGHT statement for weighted analysis

  • uses the FREQ statement for grouped analysis

  • uses the OUTPUT statement to produce a data table that contains predicted probabilities and other observationwise statistics

  • uses the BAYES statement to perform Bayesian estimation for all models except Conway-Maxwell-Poisson models and panel models

  • uses the PRIOR statement to set prior distributions for Bayesian estimation

  • supports effect-selection methods

Last updated: November 24, 2025