Two sources that disagree

Two credible pieces reaching opposite conclusions.

These two sources disagree. Work out whether it is a real disagreement or two people answering different questions. Tell me what each would need to be true, where the evidence is thinner, and which I should believe today. If neither is well supported, say that rather than splitting the difference.

Source A:


Source B:

Reading and synthesis. Getting the substance out of a document, and reconciling sources that do not quite agree.