Union
$$A \cup B =$$
{ agreeableness, conscientiousness, earth, extraversion, fire, metal, neuroticism, openness, water, wood }
Symmetric Difference
$$A \ominus B =$$
{ agreeableness, conscientiousness, earth, extraversion, fire, metal, neuroticism, openness, water, wood }
Cartesian Product
$$A \times B =$$
{ (agreeableness, earth),
(agreeableness, fire),
(agreeableness, metal),
(agreeableness, water),
(agreeableness, wood),
(conscientiousness, earth),
(conscientiousness, fire),
(conscientiousness, metal),
(conscientiousness, water),
(conscientiousness, wood),
(extraversion, earth),
(extraversion, fire),
(extraversion, metal),
(extraversion, water),
(extraversion, wood),
(neuroticism, earth),
(neuroticism, fire),
(neuroticism, metal),
(neuroticism, water),
(neuroticism, wood),
(openness, earth),
(openness, fire),
(openness, metal),
(openness, water),
(openness, wood) }
Big Five personality traits