Practice question · Sort into groups
Sort each real-world variable by its likely skew.
Groups: Right (positive) skew · Left (negative) skew
- Age at death in a country with good healthcare
- Reaction times (cannot go below zero, occasionally very slow)
- Personal wealth across a country
- Scores on a very easy quiz
Hints
- Decide which end has the long, thin tail of rare extreme values.
- Rare very-high values (wealth, slow reaction times) skew right; rare very-low values (failing an easy quiz, dying young) skew left.
Show the answer
Right (positive) skew: Personal wealth across a country, Reaction times (cannot go below zero, occasionally very slow)
Left (negative) skew: Scores on a very easy quiz, Age at death in a country with good healthcare
Why
Wealth and reaction times have rare very-high values (right tail); easy-quiz scores and age at death have rare very-low values (left tail). The rare extreme end is the tail, and the tail names the skew.
Practise Data Distributions and Skewness
The app has 6 more questions on this lesson, and keeps your place in the course. Psychology I is free to start.
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