(a) Show that the diagonal entries of a positive definite matrix
are positive numbers.
(b) Show that if B is a nonsingular square matrix, then
BTB is an SPD matrix.(Hint. you simply need to show the
positive definiteness, which does requires the nonsingularity of
B.)
a) Show that if A is a real, non-singular nxn matrix, then
A.(A^T) is positive definite.
b) Let H be a real, symmetric nxn matrix. Show that H is
positive definite if and only if its eigenvalues are positive.
b) a matrix is skew symmetric if AT=-A.If A is a
skew-symmetric matrix of odd order,show that A is not
invertible
c)Let A and B be n*n matrixes with detA=detB not equal to 0,If a
and b are non zero real numbers show that det
(aA+bB-1)=det(aB+bA-1)
Rules for positive definite matrix.
What are they? My text book explains them in a very confusing
way.
Also:
"A matrix A is said to be positive definite if it is symmetric
and if and only if each of its leading principal sub matrices has a
positive determinate"
How do I get the leading principal sub matrices?
Let A be a 2×2 symmetric matrix. Show that if det A > 0 and
trace(A) > 0 then A is positive definite. (trace of a matrix is
sum of all diagonal entires.)
Based on the confusion matrix what would be the answer?
True Positive equals 40, false positive equals 30, false
negative equals 10, true negative equals 60