Table 4.

Hypotheses Tested in Study 1 and Support (or not) for the Hypotheses.

No.	Hypotheses	Support
1	People with liberal, compared to conservative, ideologies will show greater concern for others’ outcomes.	+
2	People with liberal, compared to conservative, ideologies will cooperate more in social dilemmas.	−
3a	The relation between political ideology and concern for others’ outcomes is mediated by an egalitarian motive.	+
3b	The relation between political ideology and cooperation is mediated by an egalitarian motive.	−
4a	Conservatives, compared to liberals, will trust others less in social dilemmas (i.e., expected cooperation).	−
4b	The relation between political ideology and cooperation is mediated by trust in others (i.e., expected cooperation).	−
5a	Democrats are more cooperative with Democrats than with Republicans; and Republicans are more cooperative with Republicans than with Democrats (i.e., in-group favoritism).	+
5b	People will show greater trust in in-group, than out-group, members.	+
5c	Trust in in-group members will mediate in-group favoritism in cooperation.	+
6	People high in SDO will cooperate more with in-group, than out-group, members.	−
7	People high in RWA will cooperate more with in-group, than out-group, members.	−

Note: SDO = social dominance orientation; RWA = right-wing authoritarianism.

+indicates rejecting the null hypothesis in support of the hypothesis.

− indicates failure to reject the null hypothesis and no support for this hypothesis.