Variance

[markub3327]

Hi,

exists any proof for these equations?

I understand it as condition probability with multiple conditions, that is defined as:

x_0 is as I understand from real data distribution that could not be Gaussian.
x_t is a combination of x_0 distribution and Gaussian distribution parametrised by β_t.

Similarly in the DDIM is not the proof behind the mean and variance definition:

Thanks.

[AugChiang]

I recommend reading this blog! https://lilianweng.github.io/posts/2021-07-11-diffusion-models
It really helps me to understand the whole equations.