@splinterboost is an example for an auto-vote - I have just published this article, and already got a vote from it. It's not huge, but it occurs without review - nobody can read an article that long in 20 seconds :-D I don't know if they have algorhythms in place that help against abuse.
Another part are voting trails - one can follow a trail of a person they trust, and automatically vote on the articles that person is curating. I do that, too, because it also leads me to interesting articles. As example, I found the value post by following a downvote-trail which lead me to downvotes on comments from someone who likes to insult a lot, like really a lot. That rude person now tags me regularly in rant-posts about downvoting trails, which is interesting to read since it gives a different perspective.
@splinterboost is awesome. I have about 1400 HP delegated to them and they pay me in hive every day (usually between 0.3 and 0.6). I don't know their algorithm, but they do have one. In the past I know that they didn't give upvotes for posts under a certain word count.
Thank you for letting me know! I have 100 HP delegated to them, which is a lot - I was thinking about undelegating until my own stake grows more, but until now, I haven't decided on it yet :-D