Political ideology has been hypothesized to be associated with cooperation and national parochialism (i.e., greater cooperation with members of one's nation), with liberals thought to have more cooperation with strangers and less national parochialism, compared to conservatives. However,...

Political ideology has been hypothesized to be associated with cooperation and national parochialism (i.e., greater cooperation with members of one’s nation), with liberals thought to have more cooperation with strangers and less national parochialism, compared to conservatives. However,...

Some policy problems pit the interests of one group against those of another group. One group may, for example, determine the provision of a project (such as a power plant or a dam) that benefits group members but has downstream externalities that hurt people outside the group. We introduce a...