Triple-double (volleyball) Triple-double (volleyball) Triple-double is defined as an individual performance in which a player accumulates a double digit number total during one match in three of five statistical categories: Aces, kills, blocks, digs, and assists. The expression probably came from similar basketball jargon; the term "triple-double" was coined by former Los Angeles Lakers public relations director Bruce Jolesch in order to showcase Magic Johnson's versatility. The most common way for a player to achieve a triple-double is with kills, blocks, and digs, usually attained by hitters (i.e., middle blockers or outside hitters) who are skilled defensively. Occasionally, setters record a triple-double,
Quadruple product Quadruple product In mathematics, the quadruple product is a product of four vectors in three-dimensional Euclidean space. The name "quadruple product" is used for two different products, the scalar-valued scalar quadruple product and the vector-valued vector quadruple product or vector product of four vectors . The scalar quadruple product is defined as the dot product of two cross products: where a, b, c, d are vectors in three-dimensional Euclidean space. It can be evaluated using the identity: or using the determinant: The vector quadruple product is defined as the cross product of two cross products: where a, b, c, d