[Air-L] Effectiveness of Online Petitions

Hi folks These days I am receiving as many as 5 online petitions for various causes, all important and just in my view. I am curious if any one here could point me to  articles or book chapters, preferably based on empirical research, that address the issue of effectiveness.  Best, Rhiannon Rhiannon Bury Associate Professor Women's and Gender Studies Athabasca University, Canada's Open University rbury@athabascau.ca