Anchor with just one feature
KimBenjaminTang opened this issue · comments
Hello, I was experimenting with the provided jupyter notebook "Anchor for text.ipynb" and changed the example text "This is a good book ." to a much longer text (an actual book review)
For some reason though, the resulting anchor only shows one feature/anchor and nothing else seems to be considered. Is that the intended behavior or are longer texts not suitable with anchor?
Take a look at the examples (click the little boxes below). I'm guessing the model being used has a bias for predicting positive, such that even replacing most tokens in your long review with UNK does not cause a prediction of negative. If that is the case, an empty anchor or any arbitrary anchor is 'correct', i.e. under the assumption that the perturbation is replacing things with UNK this is a sufficient condition for a prediction of 'positive'.
Ah okay, I understand it now, thanks!
It just surprised me that out of this long text as input, only one word was selected as the anchor. But I understand it with those examples better.