Am 05.01.2017 um 12:59 schrieb Nik Pouranis: Hi, have you read chapter 19 of the manual? ("Dynamic panel models") If not, please do. If anything remains unclear, you're welcome to ask. (As per the second part of the question, I can already tell you there is no universal answer. Which IMHO is often a big problem of these methods, but that's a general property of instrumental-variable based approaches.) cheers, sven