Given that each item shows a positive or negative number as its rating, it is unclear to me what the effect of a 5-, 3-, or 1- star ratings is against the net score for that item. I'm reasonably certain what the net effect will be, but it isn't totally obvious. The fact that it isn't so obvious is a friction point that makes me somewhat less likely to interact.
Using the familiar pattern of the binary up/down as arturadib has suggested (and taking a page from StackOverflow, Reddit, etc.) would make the interface much more familiar to me.
Though a binary up/down system would make this point irrelevant, I'll add it to the conversation anyway: It seems to me that over a long enough period of time, the rating for many items (using a 5 star system) will average near 3.
Congratulations on getting Listry out in the wild. Looking forward to witnessing future developments!
There may be value in the determination of consumer-side article rank by a (weighted) average that encompasses both the net rank of items posted to the article + the rank of the article itself.
I'm sure you've already thought about the item/article interaction in terms of effect on overall article ranking. UI/X-side, the effect (of ranking an item within an article) is unclear now, and I am fine with that as an early user.
Moving forward, developing a ranking formula that weighs article rank against net rank of all of the article's items will be a usage-informed improvement that provides great value to users.
That ranking formula, as well as making the result of a "ranking" interaction obvious to the user, will help the understanding of how such interactions work.
With a social answering/ranking/voting application, creation of, and/or tweaks to, the formula that determines the effect of interactions will have a huge influence in shaping the culture of the individuals that interact with the application.
Some people may express their honest preference, but a major motivation for people to interact with something like this is to change the average, and voting at the extremes maximizes their power.
* https://www.nytimes.com/2011/08/21/magazine/do-you-suffer-fr...
So you really won't be losing much information with a two value (eg, upvote/downvote) system.