Necessary AssumptionDiff: Medium
Logic Breakdown
Passage Summary: Pollsters use census data to make sure their surveys represent the whole country. Even though the census is required now, some people skip it. If it weren't required, even fewer would do it, making the data pollsters use less accurate.
Conclusion: Making census participation voluntary would result in less accurate polling data for national opinions.
Reasoning: Researchers rely on census data for demographic accuracy; if participation drops (which it would if voluntary), the data set used to build these samples becomes less reliable.
Analysis: The argument assumes that a lower participation rate automatically leads to less accurate demographic representation. It is possible that even with fewer people, the type of people who respond still accurately reflects the national demographics. We need to assume that those who would stop participating are demographically different from those who would continue, or that the sheer volume loss makes the data unrepresentative.
Conclusion: Making census participation voluntary would result in less accurate polling data for national opinions.
Reasoning: Researchers rely on census data for demographic accuracy; if participation drops (which it would if voluntary), the data set used to build these samples becomes less reliable.
Analysis: The argument assumes that a lower participation rate automatically leads to less accurate demographic representation. It is possible that even with fewer people, the type of people who respond still accurately reflects the national demographics. We need to assume that those who would stop participating are demographically different from those who would continue, or that the sheer volume loss makes the data unrepresentative.
Passage Stimulus
Passage Redacted
Unlock Full Passage7.Which one of the following is an assumption on which the pollster's argument depends?
Correct Answer
C
C is necessary. It states that the voluntary-participant group would differ demographically from the mandatory-participant group—exactly what’s needed to make census-based sampling less representative. Negation test: if the voluntary group did not differ demographically from the mandatory group, then even with fewer participants, census data would still reflect the population’s demographics closely enough, and poll accuracy would not necessarily decline. That directly undermines the conclusion, confirming C is required.
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