What Color Is Your Aura?

What it takes for a questionnaire to count

Building a personality measure that psychologists will actually use is slow, unromantic work. It starts with a large pool of candidate items, which is then cut down by looking at how real respondents answer. Items that everybody agrees with, or that nobody understands the same way, get thrown out. Factor analysis shows which of the survivors cluster together, and those clusters become the scales.

Then the scale has to earn three separate kinds of trust. Internal consistency asks whether items meant to measure the same thing actually agree with each other; the familiar summary statistic is Cronbach's alpha. Test-retest reliability asks whether people score roughly the same when they answer again a few weeks later, because a trait score that lurches about is measuring mood or noise rather than a trait. Construct validity is the hardest: scores must correlate with things they ought to correlate with, such as ratings from people who know the respondent well, and conspicuously fail to correlate with things they should not.

Add norms drawn from thousands of respondents so a raw number can be interpreted, plus evidence that the scores predict something outside the questionnaire itself, and you are typically several years and several papers into the project. Translate it into another language and much of that work has to be repeated, because a question that works in one culture can land quite differently in the next.

Colour is a vocabulary, not a measurement

None of that applies to an aura quiz, and it would be strange to claim otherwise. Five colours have been given five appealing descriptions, options have been mapped to them by an author's judgement about which answer suits which mood, and nobody has checked whether you would land on the same colour next month. As the quiz itself cheerfully admits, this is a parlour game.

It is still a decent one. Colour words are a compact way of describing how a person tends to arrive in a room, and there is genuine pleasure in being described well, even by something with no claim to accuracy. The line worth keeping clear is the one between an entertaining description and a measurement, because the entertaining description asks nothing of you and the measurement has to earn its keep.