How they are counting whether a pin is popular or not? I had something like this in mind:
{reposts}*150+{comments}*100+{likes}*50-{time}/150
They probably won't tell anyone outside... But from my experience, popularity algorithms start off like the one you suggested, but tend to be refined and get more complex over time. Every similar algorithm I have been developing so far kept evoluting for months even after go live. As people try to trick the algorithm into making their own stuff more popular than other stuff, additional constraints are added to avoid this.
Most probably there will be more factors involved, e.g.
- clicks
- score depending on user score of the users who took action (reposted, commented, ...), i.e. commented twice by "VIP" users is more popular than commented twice by newbies
- ...
来源：https://stackoverflow.com/questions/12472365/what-is-the-pinterests-popular-pins-algorithm