I am currently writing my masters thesis in computer science. I've heard that one should avoid writing "I".
In cases where one describes what was done and it doesn't matter who did it, I understand why writing "I" should be avoided. I, however, wonder if it is ok in the following case:
In the following, it is assumed that the reader knows XYZ. In case the reader needs a refresher on any of those topics, I recommend ...
It is a subjective statement which is not necessary, but might help students who might in future read it. I should probably point out that a CS master thesis is expected to have about 80 pages, hence length-wise it doesn't really matter. It should be clear that it is subjective; if I changed it to the passive (it is recommended...) then it sounds as if there is a consensus in the community.
Some people recommend writing "the author". It, however, sounds strange and it is absolutely clear that "I" is "the author". Hence I don't see an advantage in doing so except for beating automatic tools / grading sheets.