Several writers have claimed that Gilens and Page show that America is an oligarchy. But thats not quite what their study actually found.
For starters, they show that policy preferences are widely shared between middle-class and upper-income Americans. The correlation between the two across nearly 1,800 polling questions is 0.78; it would be 1.00 if the two groups had the same preferences and 0.00 if their preferences were completely unrelated to each other. (It would be negative if middle class and rich preferences were opposed.)
Gilens and Page also found that policy preferences have little relation to changes in policies. The correlation between the policy preferences of the middle or rich, on the one hand, and whether or not a policy changes, on the other, is around 0.20.The policy preferences of interest groups are no more important for policy outcomes.
Policy change may be driven by things other than policy preferences. More likely, policy preferences are too complicated to be summarized by favor/oppose responses in polling questions.
Finally, Gilens and Page examine the correlations between policy change and the policy preferences of the middle class, upper-income Americans, and interest groups. In a statistical model that restricts how the preferences of these groups relate to each other and to policy outcomes, the policy preferences of the middle class bear no relationship with policy outcomes once the preferences of the rich and of interest groups are taken into account. The preferences of mass-based interest groups appear less influential than those of upper-income Americans and business groups.
It is difficult to know what to make of these results, however, since middle class and upper-income Americans hold similar preferences on most of the 1,800 polling questions, and that interest-group preference measures are not directly comparable to the measures for individuals.
There are also possible explanations that do not correspond with simple theories of unjust political responsiveness. One is that upper-income Americans vote at higher rates than middle-class Americans. Or perhaps wealthier Americans and business groups are better informed about policy, particularly the costs and benefits of those that affect them, or prefer policies that may, by some measure, actually be better.
Original Source: http://www.nytimes.com/roomfordebate/2014/04/21/do-the-rich-call-the-shots-13/policy-differences-between-classes-are-actually-few