Smartphone ban panel: correlation, causation, and hedged stance
You are listening to a three-minute panel discussion from a Japanese high school. Three students discuss a proposed ban on smartphones during lunch break. Speaker A cites a survey: 「先生の78%が、スマホが問題の原因だと言っています。」 Speaker B replies, 「その数字は問題の原因を証明していません。昼休みにスマホを使う生徒が増えたからトラブルが増えたのか、トラブルが多い学校ほどスマホを禁止したのか、わかりません。」 Speaker C says, 「でも、私は個人的には、なくしたほうがいいかなと思います。ただ、全員が同じとは限らないし……」 The chair then asks for a show of hands: two support a ban, one is undecided. You may replay the audio once. The recording includes background noise and overlapping speech; the key challenge is Speaker B's second sentence.
1. Identify Speaker B's main point and explain why the 78% statistic does not settle the debate.
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Speaker B is not denying that problems exist; she is challenging the inference from a correlation. The phrase 「証明していません」 is precise: a survey of teachers' beliefs shows what teachers think, not what causes trouble. She then offers two rival explanations: (1) more phone use during lunch caused more incidents; (2) schools with more incidents were more likely to ban phones. Both would produce the same 78% figure, so the statistic is compatible with different causal stories. A strong answer notes that Speaker A has committed a causal fallacy, while Speaker B has introduced a selection/feedback problem. The debate therefore needs evidence about timing, school policy changes, or incident records - not another opinion poll.
2. What is Speaker C's stance, and how does her language show it? Explain the effect of 個人的には and とは限らない.
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Speaker C leans toward supporting the ban but does not commit fully. 「個人的には」 frames the view as personal rather than evidence-based, which lowers the force of the claim; 「かなと思います」 adds further softening. 「全員が同じとは限らないし……」 introduces a reservation: she recognises that other students may not share her preference, and the trailing し leaves the list of reasons open. In the show of hands she is the undecided vote, which matches the hedging. Her language is not evasive for its own sake: it signals that she has a preference but sees the policy as one where reasonable people disagree. An answer that calls her 'strongly in favour' misreads the modality.