Imagine a hypothetical study using a nonequivalent comparison group designed to assess the effectiveness of an anti-drug, "Just Say No," campaign. In this study students at school X receive a semester-long series of "Just Say No" lectures
Students at school Y across town do not receive the intervention. Unfortunately, during the semester a student at school Y died after an accidental drug overdose. This incident may have influenced drug use at school Y (but not school X) and consequently make it impossible to interpret our research findings. Which of the following threats to internal validity is present in this study?
a. selection-instrumentation
b. selection-maturation
c. selection-history
d. selection-testing
C
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If the goal is to have candidates who represent as broad a section of society as possible, it would be best to use a(n) __________
a. closed primary b. open primary c. open caucus d. proportional primary e. modified closed primary
Which of the following plans proposed proportional representation for the U.S. Congress?
A. New Jersey B. Ohio C. Pennsylvania D. Virginia