Reading a score
How to read an IPIP-NEO score
A score is a position on a scale, and what it means depends on the scale. Six steps, in the order that avoids the usual mistakes.
A 70 does not mean you beat 70% of people. It means your answers were worth 70% of the maximum.
- Start with the five domains. They are the most dependable numbers in the report, because each one pools many questions. Look at them first and treat the facets as detail.
- Know which number you are looking at. A domain score is usually a percent of the maximum: total points divided by the highest possible total. A percentile is a rank among other people. They are different things, and a report should say which one it gives.
- Do not compare domains with each other. Scales sit at different heights. In a sample of JobCannon test-takers the average Openness score was about 65 and the average Neuroticism score about 46, so a 60 on each does not mean the same thing.
- Turn a score into a position only with a reference sample. A percentile needs the scores of a group to compare against, and it describes that group. A score that is high among university students can be average in another population.
- Read a score as a range. Every score carries measurement error. In 3,079 completed IPIP-NEO-120 results, a domain score on the 0–100 scale had a standard error of measurement of 5.1 to 5.5 points (technical manual), so a difference of a few points between two domains, or between two testings, is within noise.
- Then look inside a domain. The facets show where a domain score comes from. Two people with the same Conscientiousness can get there through Orderliness or through Achievement-Striving. Facets in the 120-item version rest on four questions each, so read them as pointers.
High is not good, low is not bad
Each end of a trait has strengths and costs, and which one fits depends on the setting. The facet and domain names borrow everyday words, but a score describes a trait, which is a different thing from a clinical condition.
Mood and context
People answer in a particular mood, on a particular day. A retake will rarely return identical numbers, and the differences you see are mostly measurement error and mood, not a change of personality.