Studies have suggested that some special interest groups lobby for less immigration for their own group and more immigration for other groups since they see effects of immigration, such as increased labor competition, as detrimental when affecting their own group but beneficial when impacting other groups. A 2010 European study suggested that "employers are more likely to be pro-immigration than employees, provided that immigrants are thought to compete with employees who are already in the country. Or else, when immigrants are thought to compete with employers rather than employees, employers are more likely to be anti-immigration than employees." A 2011 study examining the voting of US representatives on migration policy suggests that "representatives from more skilled labor abundant districts are more likely to support an open immigration policy towards the unskilled, whereas the opposite is true for representatives from more unskilled labor abundant districts."