3.A Source Reliability, Bias, and Limitations (CLE-1.Q, CLE-1.S, CLE-1.T)

Every source has a position: who funded it, who collected its data, what it was trying to prove. That position doesn't disqualify the source, but it tells you how much weight to put on its numbers. A study funded by the company whose product it tests can still report true data, but a reader has to ask whether the questions asked, or the population sampled, were shaped by that interest. The clearest sign of bias isn't a scary funder name — it's whether the source engages rival positions. A source that raises the strongest objections to its own claim and answers them is doing honest work even if it has a stake in the outcome. A source that pretends no counterargument exists is the one to worry about.

Limitations are different from bias. A limitation is a structural gap — an old sample, a narrow population, a method that can't capture what the claim is about. The move is not to throw the source out, but to name the gap and reason around it: cite the number, say plainly what it can't show, and use another source or your own logic to cover the distance. A 2003 phone survey of landline owners can't describe today's teenagers, because landline households back then skewed older and wealthier — no amount of additional respondents fixes a frame that excluded the right population from the start.

This is why synthesis is a conversation, not a pile of citations. When you place your thesis as a node among sources, you're drawing edges that show where sources agree, disagree, or share a blind spot. A set of sources that all stand in the same place — same funding, same institution, same angle — can each be individually careful and still leave a hole in the argument exactly where someone unlike them would object.