How Watson Glaser inference questions work
Each set opens with a short passage of facts, followed by several statements someone might infer from it. You rate each statement on its own, using what the passage says rather than what you happen to know.
True means the facts prove the statement. Probably True means they make it more likely true than false. Insufficient Data means they point neither way. Probably False and False are the mirror images of the first two.
Inference is the only section with five answers rather than two, and your raw score counts only correct answers, so Probably True for a True statement earns nothing.
How to answer an inference question
Take each statement through these steps in order:
- Decide the direction first. Does the passage push the statement towards true, towards false, or nowhere?
- If it points nowhere, the answer is Insufficient Data. Stop there.
- If it points one way, ask whether the facts settle it. Settled means True or False; anything short of that means Probably.
- Before choosing True or False, find the sentence that proves it. If you cannot point to one, drop to Probably.
- Check you have not filled a gap with your own knowledge or opinion. If you have, the answer is usually Insufficient Data.
Worked example
Passage: A railway station replaced its staffed ticket office with ticket machines in March. Over the next six months, the average queue time fell by a third. Over the same period, the number of passengers aged over 70 using the station fell by 15 per cent. Train times and fares have not changed in the past two years.
- “Fares did not change when the ticket office closed.” True. Fares have not changed for two years, which covers March.
- “Some older passengers found the machines harder to use than the ticket office.” Probably True. Fewer over-70s travelled straight after the change while times and fares stayed the same, which points this way without proving it.
- “The ticket office staff were moved to other jobs at the station.” Insufficient Data. The passage says nothing about the staff.
- “Passengers over 70 were happier with the station after the change.” Probably False. Fewer of them used it, which suggests the opposite, though it is not certain.
- “Queues got longer after the machines arrived.” False. The passage says the average queue time fell by a third.
Tips for the real inference questions
- Save True and False for statements the passage settles outright.
- Do not let a plausible statement pull you to Probably True. Sounding likely is not evidence.
- Watch the scope words: all, some, only, usually. A statement that says “all” where the passage says “most” cannot be True.
- Go back to the exact line each statement relies on rather than answering from memory of the passage.
- Pace yourself across the whole test. At 30 minutes for 40 questions you have 45 seconds a question.
Practise Inference on CogniPrep
Our Inference game gives you 12 statements a run, drawn from a pool of 24, with 50 seconds on each and no going back. A statement left unanswered when time runs out counts as wrong. Your score out of 100 is mostly accuracy, with smaller parts for pace, for avoiding answers two or more steps out and for getting Insufficient Data right. It gives half credit for a rating one step away, which the real test does not, and the 50-second clock is ours: Pearson only times the test as a whole.