the amount (of money or goods or services) that is considered to be a fair equivalent for something else; "he tried to estimate the value of the produce at normal prices"
relative darkness or lightness of a color; "I establish the colors and principal values by organizing the painting into three values--dark, medium...and light"-Joe Hing Lowe
evaluate or estimate the nature, quality, ability, extent, or significance of; "I will have the family jewels appraised by a professional"; "access all the factors when taking a risk"