# Singular matrices

1. Feb 23, 2007

### calli

1. The problem statement, all variables and given/known data

Hi, no variables, eqns or any of that here:) I was hoping some of you brilliant people could help me in finding some real world examples of where singular matrices occur. I do know that most real world problems yield matrices that are singular and therefore not invertible. We can use a generalized inverse on these problems, but im finding it difficult to find some real world examples of this, specifically in the field of finance.

2. Relevant equations

3. The attempt at a solution

2. Feb 24, 2007

### SGT

In real world applications singular matrices occur very seldom, since the elements are real numbers.
What is common is badly conditioned matrices: matrices whose determinant is not zero, but is very close to. In this case, small fluctuations in any parameter yields enormous variations in the result.

3. Feb 24, 2007

### calli

singularity

hey thanks so much.

I have been looking at ill-conditioned matrices. I was hoping to find some specific financial application that yields ill-conditioned matrices. (i.e. there condition number is very large)

4. Feb 24, 2007

### SGT

What makes a matrix singular or ill-conditioned is the value of the elements. Any application can have those types of matrices, depending on the data.