Perform a likelihood ratio chi-squared test for nu = 1 of a COM-Poisson model. The test statistics is calculated as 2*(llik- llik_0) where llik and llik_0 are the log-likelihood of a COM-Poisson and Poisson model respectively. The test statistic has 1 degrees of freedom.
LRTnu(object, digits = 3)an object class 'cmp', obtained from a call to glm.cmp
numeric; minimum number of significant digits to be used for most numbers.
Huang, A. (2017). Mean-parametrized Conway-Maxwell-Poisson regression models for dispersed counts. Statistical Modelling 17, 359--380.
data(takeoverbids)
M.bids <- glm.cmp(numbids ~ leglrest + rearest + finrest + whtknght
+ bidprem + insthold + size + sizesq + regulatn, data = takeoverbids)
LRTnu(M.bids)
#>
#> Likelihood ratio test for testing nu=1:
#>
#> Log-Likelihood for Mean-CMP(1.75214): -180
#> Log-Likelihood for Poisson: -185
#> LRT-statistic: 9.72
#> Chi-sq degrees of freedom: 1
#> P-value: 0.00182