Parameter Significance (Wald Test)
For each estimated parameter
, the Wald chi-square statistic is the quantity:
where
is the estimated variance of
as defined in Parameter Variances and Covariances.
p-Values
The p-value for each parameter estimate
is the probability of seeing the value of the calculated parameter using the above formula, or something more extreme, if the hypothesis bj = 0 is true. Note that in general the sample size must be large in order for the p-value to be accurate.
Critical Values
The critical values, vj , for the parameter estimates are the levels at which, if the absolute value of the Wald chi-square statistic calculated for a given
is greater than vj, we reject the hypothesis bj = 0 at the specified significance level.