Right angle Right angle In geometry and trigonometry, a right angle is an angle of exactly 90° (degrees), corresponding to a quarter turn. If a ray is placed so that its endpoint is on a line and the adjacent angles are equal, then they are right angles. The term is a calque of Latin "angulus rectus"; here "rectus" means "upright", referring to the vertical perpendicular to a horizontal base line. Closely related and important geometrical concepts are perpendicular lines, meaning lines that form right angles at their point of intersection, and orthogonality, which is the property of forming right angles, usually applied
Less-is-better effect Less-is-better effect The less-is-better effect is a type of preference reversal that occurs when the lesser or smaller alternative of a proposition is preferred when evaluated separately, but not evaluated together. The term was first proposed by Christopher Hsee. In a 1998 study, Hsee, a professor at the Graduate School of Business of The University of Chicago, discovered a less-is-better effect in three contexts: "(1) a person giving a $45 scarf (from scarves ranging from $5-$50) as a gift was perceived to be more generous than one giving a $55 coat (from coats ranging from $50-$500); (2) an overfilled ice