9bf83e98_ing_Many_Additional_Resources___3
[0] observation [1] to gather accurate information about how a program actually operates, particularly about processes [2] -view operations of a program as they are actually occurring -can adapt to events as they occur [3] 
-can be difficult to interpret seen behaviors -can be complex to categorize observations -can influence behaviors of program participants -can be expensive
Basic Guide to Program Evaluation (Including Many Additional Resources)
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