The text, statistics, and graphics in a source must help satisfy your assignment's requirements.

Usually, more than 1 source is necessary and every source should be evaluated.

When evaluating a source, figure out:

Does this contain
well supported arguments and
valid research?

• deciding if you're looking at the full text (complete) document or only an abstract (summary)

full text is usually required for your assignment

• deciding if you're looking at a primary source (raw data or original account of an event) or a secondary source (analysis or interpretation of data and events)

either type may be acceptable for an assignment

• deciding if a particular bias or a balanced point of view is given

either type may be acceptable for an assignment

• making sure opinions and conclusions are supported by sufficient research, statistics, or other valid evidence

there should be no gaps in the author's logic

• checking how quotations, statistics, and facts were collected and to whom they were credited

all sources should be cited so they can be checked, if necessary

• scanning the bibliography to see what types of sources the author used

decide if the source is primarily fact or opinion - either may be acceptable for an assignment