What is the difference between the sortino and the omega ratio?

1

Omega uses standard deviation of negative returns for the denominator and sortino uses standard deviation of total returns in the denominator.

2

Omega uses a probability density function of negative returns for the denominator and sortino uses downside deviation for the denominator.

3

There is no difference, they both use the accumulated variability of returns to make a judgement on portfolio efficiency.

4

Omega uses semivariance for the denominator and sortino uses the probability density function of negative returns in the denominator.

5

Omega uses semivariance for the denominator and sortino uses semivariance in the numerator.