N=1 designs are also known as designs

In terms of "left-right" orientations, the bulk of the voters in the United States are

A. left and tend to be Democratic. B. far-left. C. center-right. D. center-left.

Which of the following conditions, if true, would eliminate the free rider/collective action problem?

a. if participation in an interest group were mandatory b. if members were allowed to vote on matters of concern to the interest group c. if participation in an interest group were voluntary d. if the leaders of an interest group were able to set the group's priorities e. if an interest group focused on providing benefits to society as a whole