Dear all, Could anyone let me know what order of approximation (first, second or higher order) is used in glmmPQL in the MASS library please? I have read the section on this wrapper command in Venables and Ripley but am not sure if the relevant information is there. Many thanks in advance. Best wishes, Edmond *************************** Edmond Ng Research Fellow Graduate School of Education 35 Berkeley Square Bristol BS8 1JA United Kingdom