Sigma (/ˈsɪɡmə/ SIG-mə; uppercase Σ, lowercase σ, lowercase in word-final position ς; Greek: σίγμα) is the eighteenth letter of the Greek alphabet. In...

mathematical analysis and in probability theory, a σ-algebra (also σ-field) on a set X is a nonempty collection Σ of subsets of X closed under complement, countable...

p ( σ 2 ∣ ν 0 , σ 0 2 ) = ( σ 0 2 ν 0 2 ) ν 0 / 2 Γ ( ν 0 2 )   exp ⁡ [ − ν 0 σ 0 2 2 σ 2 ] ( σ 2 ) 1 + ν 0 2 ∝ exp ⁡ [ − ν 0 σ 0 2 2 σ 2 ] ( σ 2 ) 1...

σ ) = φ ( ln ⁡ x − μ σ ) d d x (   ln ⁡ x − μ   σ ) = φ (   ln ⁡ x − μ   σ ) 1   σ   x   = 1   x   σ 2   π     exp ⁡ ( −   ( ln ⁡ x − μ ) 2   2   σ 2...

Look up sigma, Sigma, Σ, σ, or ς in Wiktionary, the free dictionary. Sigma (Σ or σ, word-final lowercase ς) is the 18th letter of the Greek alphabet. Sigma...

is said to be σ-compact if it is the union of countably many compact subspaces. A space is said to be σ-locally compact if it is both σ-compact and (weakly)...

anticommutator gives [ σ j , σ k ] + { σ j , σ k } = ( σ j σ k − σ k σ j ) + ( σ j σ k + σ k σ j ) 2 i ε j k ℓ σ ℓ + 2 δ j k I = 2 σ j σ k {\displaystyle...

defined on a σ-algebra Σ of subsets of a set X is called a finite measure if μ(X) is a finite real number (rather than ∞). A set A in Σ is of finite measure...

measure theory and functional analysis — the cylindrical σ-algebra or product σ-algebra is a type of σ-algebra which is often used when studying product measures...

] = 3 σ i i 2 E ⁡ [ X i 3 X j ] = 3 σ i i σ i j E ⁡ [ X i 2 X j 2 ] = σ i i σ j j + 2 σ i j 2 E ⁡ [ X i 2 X j X k ] = σ i i σ j k + 2 σ i j σ i k E ⁡...