Survey Evidence and a Phone Ban
A school council debates a proposal to ban mobile phones during the 20-minute break. The proposal cites a survey sent to 40 teachers and 300 students; 18 teachers and 90 students responded. Of the 18 teachers, 12 (66.7%) said phones distract students; of the 90 students, 43 (47.8%) said they use phones to contact family about pickup changes. The survey was conducted online, and the council did not report how the sample was chosen. A council member writes: 'The data prove that phones are a problem, because most teachers say so, and students who disagree only want to play games.' Another member says the survey cannot support a general rule.
1. In the quoted sentence, identify one factual claim and one opinion. Explain the difference using the survey numbers.
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Factual claim: 'most teachers say so' can be checked against the survey. Of the 18 teachers who responded, 12 said phones distract students, which is 66.7% of respondents. Opinion: 'students who disagree only want to play games' is a judgment about motives; the survey did not ask why students disagreed, and 47.8% of responding students gave a practical reason (pickup messages). Facts can be verified; opinions evaluate or speculate and need evidence.
2. Calculate the response rates for teachers and students. Explain why the statement 'most teachers say so' cannot be used to claim that most of the 40 teachers support the ban.
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Teacher response rate = 18/40 = 45%. Student response rate = 90/300 = 30%. Among responding teachers, 12/18 = 66.7% said phones distract. But that is only 12/40 = 30% of all teachers in the survey pool. The 22 teachers who did not respond could be more supportive, more opposed, or indifferent. Similarly, 43/90 = 47.8% of responding students, but only 43/300 = 14.3% of all students. With low response rates and an online, self-selected sample, 'most teachers' is an overgeneralization.
3. Rewrite the quoted sentence so it is precise and fair. Use at least one number, avoid 'prove', and do not guess students’ motives.
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Precise rewrite: 'In an online survey, 12 of the 18 teachers who responded (66.7%) said phones distract students, and 43 of the 90 responding students (47.8%) said they use phones for pickup messages. Because only 45% of teachers and 30% of students responded, these results describe the respondents but do not prove a rule for the whole school.' This uses numbers, avoids 'prove', and does not guess students' motives.