IB Psychology 2027 · Concepts
PsychExcel concept resources
The six course concepts are bias, causality, change, measurement, perspective and responsibility.
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Learn the six concepts as ways of thinking.
Bias in IB Psychology: How to Use the Concept in Exam Answers
Bias pushes rather than scatters, which is why more data will not fix it. The six places it enters a study, how to name a direction, and why choosing one bias beats listing six.
Read guideCausality in IB Psychology: How to Use the Concept in Exam Answers
Causal claims come in six strengths. Which rung a design reaches, the seven alternatives worth having ready, mediator versus moderator, and why "correlation is not causation" is a retreat.
Read guideChange in IB Psychology: How to Use the Concept in Exam Answers
Change is four questions, not one. Did it change, did it last, did it matter, and would it have happened anyway. Plus why "effective" can mean five different things.
Read guideMeasurement in IB Psychology: How to Use the Concept in Exam Answers
Measurement is a bridge, not a window, and the number is not the thing. The comparison that catches most overclaiming, why reliable is not valid, and what changes when a measure is used on people.
Read guidePerspective in IB Psychology: How to Use the Concept in Exam Answers
Perspective is the lens most often missed because it hides inside evaluative words. How to spot it, how it differs from bias, and the point at which a standpoint crosses into one.
Read guideResponsibility in IB Psychology: How to Use the Concept in Exam Answers
Responsibility is about how psychological knowledge is produced and used, not about whether someone deserves blame. The four links in the chain, the evidential bar, and the question that lifts an answer.
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