Policy debate is a form of debate competition in which teams of two advocate for and against a resolution that typically calls for policy change by the United States federal government. It is also referred to as cross-examination debate (sometimes shortened to Cross-X, CX, Cross-ex, or C-X) because of the 3-minute questioning period following each constructive speech. Evidence presentation is a crucial part of Policy Debate; however, ethical arguments also play a major role in deciding the outcome of the round. The main argument being debated during a round of Cross Examination is which team has a greater impact. This factor alone can decide the winner of a round. Whichever team can prove the greater impact is likely to win the round. When a team explains why their impacts are "greater" than the opposition's impacts, they utilize the concept of "impact calculus." One team’s job is to argue that the resolution— the statement that we should make some specific change to address a national or international problem —is a good idea. Affirmative teams generally present a "plan" as a proposal for implementation of the resolution. On the other hand, the Negative teams present arguments against the implementation of the resolution. In a single round of debate competition, each person gives two speeches. The first speech each person gives is called a “constructive” speech, because it is the speech where each person constructs the basic arguments they will make throughout the debate. The second speech is called a “rebuttal”, because this is the speech were each person tries to rebut (or answer) the arguments made by the other team, while using their own arguments to try to convince the judge to vote for their team. The Affirmative has to convince the judge to vote for a change, while the Negative has to convince the judge that the status quo is better than the hypothetical world in which the Affirmative's plan is implemented.