Minimum coalitions. Political parties in parliament tend to form minimum–size winning coalitions and prefer partners located on contiguous positions along the policy–ideology space. The distribution of cabinet portfolios among coalition parties tends to be proportional to the number of seats controlled by each party.
Cabinet duration. Single–party majority cabinets tend to last longer than multiparty coalition or minority cabinets.
Two–party stalemate.In a system with division of powers between the presidency and the congress, the "deadlock interval" or range of stable policies is relatively short with multiple parties and with individual members of congress' freedom to vote. In contrast, a two–party system with strong party discipline favors confrontation and interinstitutional stalemate.