Two Sources, One Claim
A student is writing a short argument that a city should add more bike lanes. She has two sources. Source A is a city transportation department report stating that after bike lanes were installed on three streets, reported cyclist injuries on those streets fell 30% over two years. Source B is a newspaper opinion column arguing bike lanes are unpopular, citing a single neighborhood meeting where several residents complained about lost parking. The student writes: "Bike lanes reduce injuries and residents support them." Her teacher flags the second half of the sentence as unsupported by her evidence.
1. Explain precisely why the claim "residents support them" is not supported by these two sources, and rewrite the sentence so it matches the evidence.
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Why it fails: Source A addresses injuries only; it says nothing about resident opinion. Source B is an opinion column reporting complaints from one neighborhood meeting - a single, self-selected group, not a representative sample of residents. Neither source measures support across the city, so "residents support them" overreaches.
Rewrite: "Bike lanes were associated with a 30% drop in reported cyclist injuries on three streets, though some residents at one neighborhood meeting objected to lost parking."
The judgment being tested: matching the strength and scope of a claim to what the evidence actually shows, and distinguishing a representative finding from an anecdote.
2. Source B is labeled an opinion column. How should that affect how the student uses it, even if the complaints it reports are factually accurate?
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An opinion column's genre signals that its purpose is to persuade, not to report neutrally. Even if the individual complaints are accurate, the column selects and frames them to support a viewpoint, and it generalizes from one meeting.
The student can use Source B as evidence that some residents objected (a real, attributable event), but should not treat it as evidence of overall public opinion. She should attribute it ("an opinion column reported...") rather than present its framing as established fact, and she should look for a representative survey before making any claim about citywide support.