Hey Denis, I'm slowly getting myself acquainted with Otava and found your doc extremely helpful and very well written!
I'll post here some of my reading notes, slightly reworded to read like comments in case they might be useful to you. > https://github.com/apache/otava/pull/126/files#diff-b38fe588c0481132e3185c6c184fcb9a1208b32ae5a03dd92b12df4b0dfa46eeR23 Is there a practical reason to allow the first element in the data series to be a change point on its own, but not the last? If there is, it might be nice to highlight it, as it's pretty subtle just looking at the paragraph here. > This process yields a series of change points $$0 < \hat{\tau}_1 < \hat{\tau}_2 < \cdots < \hat{\tau}_k < T$$. nit: $$1 \leq \hat{\tau}_1 will be consistent with the initial definition (for me it's also less confusing, as the sequence here is not zero-indexed). > https://github.com/apache/otava/pull/126/files#diff-b38fe588c0481132e3185c6c184fcb9a1208b32ae5a03dd92b12df4b0dfa46eeR32 and > and the coefficient in front of the second and third terms in $$\hat{\mathcal{E}}$$ are binomial coefficients. Aren't the coefficients in front of these terms reciprocals of binomial coefficients? > Non-deterministicity of the results due to the permutation significance test "Result non-determinism" vs "Non-deterministicity of the results"? > Starting with a zero-indexed time series Is this fundamentally needed? The shift from the one-indexed concepts above might be slightly confusing and e.g. invalidates the boundaries for \tau and \kappa which we defined before and are using here without redefining. Maybe we should just redefine the boundaries again, alongside with s (even if it might seem obvious what it should be). > https://github.com/apache/otava/pull/126/files#diff-b38fe588c0481132e3185c6c184fcb9a1208b32ae5a03dd92b12df4b0dfa46eeR73 and > https://github.com/apache/otava/pull/126/files#diff-b38fe588c0481132e3185c6c184fcb9a1208b32ae5a03dd92b12df4b0dfa46eeR75 Should we also define base values for B(s, s + 1, \kappa) and C(s, \kappa - 1, \kappa) to avoid dividing by zero for one-element sequences? This also links to some extent with my confusion about having one-element sequences and allowing the first, but not last element to be a change point, as well as to Henrik's comment on the PR that the first element in the example image shouldn't qualify as a change point. Regards, Dimitar On Tue, 10 Feb 2026 at 06:13, Alexander Sorokoumov < [email protected]> wrote: > Thank you for this contribution, Denis! I've responded to the PR with a few > suggestions. It is an awesome improvement to our documentation that will > help with explaining how Otava works. After the PR is merged, I will also > publish it to the website. > > Best, > Alex > > On Sun, Feb 8, 2026 at 11:54 PM Denis Shchepakin < > [email protected]> > wrote: > > > Hello everyone, > > > > Created a PR with an E-divisive algorithm doc as per issue here: > > Description > > of Underlining Statistic Methods Used · Issue #100 · apache/otava > > <https://github.com/apache/otava/issues/100>. Any feedback is welcome. > > > > Best, > > Denis > > >
