We can verify that all of above complexity (nearly) matches the corresponding lower bounds.

There are mainly two types of domain adaptation formulas:covariate shift[44, 37, 29, 13] and label shift [27, 2, 1], while we focus on the former in this paper since it appears more natural in recognition tasks and attracts more attention in the literature.

And{φi(x)}arep-orthogonal: Z φi(x)φj(x)p(x)dx=δij. (4) δij is 0 when i 6= j, 1 when i = j. S(m)U(m) =U(m)Λ(m), (7) Li Zhang (lizhangfd@fudan.edu.cn) is the corresponding author with School of Data Science, Fudan University. More specifically, the relation between any two tokens is reconstructed via sampled bottleneck tokens. Further,exact Gaussian kernel attention computation leads totraining difficulties. However, it turns out to suffer from a similar failure.