Steam's Discovery algorithm got updated

Valve have recently updated Steam's Discovery algorithm, which will show users precise and more diverse games in the Recommendation Feed, as well as the "More Like This" and the "Recommended for You" sections of the store.

Valve felt that previously the algorithm would only show players some of the more popular games and the feed didn't feel very personalized, so the changes made to it should improve the number of games shown, and maybe even recommend some hidden gems:

Previously, when customers would look for games by browsing the recommendation feed at the bottom of the homepage or the "More Like This" sections, they weren't seeing as many different games as we would've liked. Furthermore, we were receiving lots of feedback that "Recommended for You," felt too biased towards only the most popular games and didn't feel very personalized. We wanted to determine how to respond to this feedback, so we went in search of bugs and decided to run an experiment.

We found some bugs, such as the "Similar by Tags" section of the Recommendation Feed, which had a bug that top-rated games (a category that doesn't change very often) were driving too much of what players saw. We changed that. We also found that in some places our timescale used to calculate popularity was too narrow, resulting in unpredictable visibility for some games. So we expanded the time period we use in those calculations.

The company wanted to ensure that all the games shown in these sections would be truly relevant to an user. They made sure the games shown would make the players engage with them (click through, wishlist the games, buy them).

In these changes, "Recommended for You" became less biased towards popular games, and showed games that are more relevant to individual customers. As it turned out, customers in the experiment group were more likely to click on the games shown in the recommendations section, at a rate almost 15% higher than the control group. The increased personalization means there is an even greater variety of games being shown in this section, and customer impressions are more evenly distributed among them.

To get a feel for the breadth of titles that were being visited, we measured how many games members of the experiment group visited via the "Recommended For You" section compared to a sample of customers who were not in the experiment for a few days. The results were very promising: we saw a 75% increase in the number of unique games visited, and a 48% increase in the average visits per game.

From the looks of it they already had some success with these changes:

Store areas driven by Tags, such as "More Like This," saw increases in purchase and wishlisting across a broader set of games. It shouldn't come as much of a surprise, but by increasing qualitative specificity and showing a wider range of titles, more customers found things they didn't know they wanted.

You can read the full article here.