It helps them determine whether an assertion made by one source is likely to be true.
FOR FARTHER EXPLANATION
Corroboration is the skill of comparing multiple sources regarding an event to find the most consistent and valid version of the event.
Political scientists would use corroboration to determine political results, polling, campaign progress, as well as bill development. A study on the passage of the Affordable Care Act for example would pull together versions of the bill as well as party opinions on the bill. In writing an assessment on the bill, the political scientists would look at all of the information and come to a conclusion.
With respect to global connections, association with "the European Union" offers the brightest immediate future for many African countries, since this union is comprised of a variety of countries with economic ties to Africa.
In the U.S. Constitution the states are subordinate to the federal government, and in the Texas Constitution the counties are subordinate to the state government.
