
Millions log into every day, letting fly with , tales of social awkwardness and . This is the war for Reddit 鈥渒arma points鈥: the crucial upvotes and downvotes from internet strangers, which govern how content is displayed across Reddit. A user鈥檚 karma score, displayed next to their username, reflects how much other people like the things they have submitted. Make no mistake, it鈥檚 a serious business.
Now computer scientists from Stanford University in California have put Reddit under the microscope. Their goal is to understand what user-controlled factors, beyond the content itself, contribute to a post鈥檚 success 鈥 and the acquisition of karma.
鈥淭here鈥檚 a very high chance that your content will get missed out on Reddit,鈥 explains lead author Himabindu Lakkaraju, who will present the work at the in Cambridge, Massachusetts, on 17 July. 鈥淲e basically asked whether branding is important on Reddit, and it turns out it is.鈥
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To explain how titles, community and timing affect posts鈥 popularity, Lakkaraju analysed an archetypal Reddit image 鈥 a . Lasers shoot from Lincoln鈥檚 eyes. It is perfect Reddit content.
The image鈥檚 first submission, to the 鈥減ics鈥 subreddit under the title 鈥淚鈥檓 not sure I quite understand this piece鈥, garnered just 62 karma points. Subreddits are where people post submissions that pertain to a specific character. But one year later an opportunistic Redditor was 10 times as successful in the 鈥渇unny鈥 subreddit, with the simple title, 鈥淢URICA鈥.
To figure out what鈥檚 driving these kinds of differences, Lakkaraju and colleagues analysed a set of 132,000 submissions. For starters, they found that each image on Reddit was resubmitted an average of seven times. They also found that Reddit has a memory, and it鈥檚 about 45 days. The chances of negative reactions to reposted content becomes much milder after that point.
There are optimal times to post too. Lunchtime is best for the most popular subreddits like pics, gaming and atheism. The team also found that some subreddits work much better for cross posting than others: reposting from 鈥済ifs鈥 to 鈥渟pace鈥 is a good idea, while 鈥渇unny鈥 and 鈥済ifs鈥 tends not to work so well.
The team took the analysis further by training a machine learning algorithm on the most successful posts in their dataset, measuring which words and combinations of words were most often associated with successful posts. This led the team to predict the popularity of Reddit posts fairly accurately, although they tend to underpredict the largest popularity spikes.
Lakkaraju says that content is important, but can only take a post so far. 鈥淧eople want to get things noticed in the community very badly,鈥 he says. 鈥淪o they think: 鈥榃hat can I do to account for the other factors so that my content gets noticed as much as possible?'鈥