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A researcher wants to know whether an educational video about genetics is effective. This researcher created a quiz assessing knowledge about genetics. She recruited 6 undergraduates and gave them the quiz as a pre-test. Then they watched the educational video, and took the test a second time.
Student Pre-test Post-test
Anne 2 7
Bob 4 5
Cathy 5 7
Dave 7 8
Emma 2 9
Fred 4 6
Compute the average difference score
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