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Criticism of research lays a significant foundation for future investigative work, but when students begin their own projects, they are likely to find that the standards of validity in field work considerably more rigorous than the standards for most library research. When students are faced with the concrete problem of proof by field demonstration, they usually discover that many of the "important relationships" they may have criticized other researchers for failing to demonstrate are very elusive indeed. They will find, if they submit an outline or questionnaire to their classmates for criticism, that other students make comments similar to some they themselves any have made in discussing previously published research. For example, student researchers are likely to begin with a general question but find themselves forced to narrow its focus. They may learn that questions whose meanings seem perfectly obvious to them are not clearly understood by others, or that questions which seemed entirely objective to them appear to be highly biased to someone else. They usually find that those who have not actually attempted it generally believe the formulation of good research questions is a much more subtle and frustrating task.
According to the passage, what do student researchers often learn when they discuss their work in class