as @waiwai933 has already found the answer, this question should not remain unanswered. Here is a formatted abstract from the relevant blog.
Here’s how it works. Starting with a list of the last 3,000 active
- drop questions containing any of your ignored tags
- drop closed questions if you lack the reputation required to vote for reopening
- drop questions scoring -4 or lower
Next, apply the following score formula to the remaining questions:
- your interesting tags +1,500 per interesting tag, up to +2,000 total
- your top 40 scoring tags maximum of +1,000 per tag (scaled), up to +2,000 total
- question score +200 × score, up to +1,000 total
- total answer score -200 × score, up to -1,000 total
- number of answers -200 × answers, up to -1,000 total
- number of views -15 × views, up to -1,000 total
- question last activity date -1 × (seconds / 15)
Count it all up and take the top 90 by score.
We also mix in a few random questions from the last 3,000 — 10% (9)
for logged in users and 20% (18) for anonymous users.