Talk Ranking: Measures of Quality

FindLectures.com ranks talks differently than Google or more traditional full text search engines.

To encourage discovering new topics, it attempts to show a variety of topics and speakers in the results, until you narrow using a search term or facets. This helps to replicate the experience of browsing a library. This is notably different from Amazon or Youtube, which show you topics based on what you previously watched.

If talks aren’t of high quality, browsing a collection at random leads to a lot of dead-ends. FindLectures tracks some quality measures to improve this experience, listed below. Most of these are experimental, so not every factor may work correctly or apply to everything.

One of the goals of FindLectures is to surface speakers who are doing interesting work, but who are not focusing on marketing their efforts. Consequently, I’ve tended to treat some ranking factors as binary values (you have written a book or you haven’t). This ideally acts as a low-pass filter on talks, without eliminating people who are early in their careers.

Note that popularity is largely ignored - I see this as a measure of how good the speaker is at marketing themselves. On social media, there are many sizeable communities that focus their efforts on rigging the rankings of various sites (e.g. Google image search, reddit, etc).

Quality factors on text

  • Does the talk start with a long introduction?
  • Does the speaker say “um” frequently?
  • Do they speak excessively quickly or slowly?
  • If the speaker uses an esoteric vocabulary, the talk may be good for practictioners of their field, but poor for others.

Speaker Attributes

  • Is the speaker getting invited to a lot of conferences? - Is there a wikipedia entry about the speaker?
  • Did the speaker write a book? Who is the publisher?
  • Does the speaker get invited to many different conferences?
  • Does the speaker get invited back to the same conference?
  • Did someone else vet this speaker? (E.g. a conference or university)

History

  • How old is the talk?
  • Are there books written about the speaker?

Audio

  • Is the audio in both channels (if stero)
  • Are there mic problems (clipping, etc)
  • How well can a machine transcribe the text? If the stated transcript is very different from a generated transcript, it may indicate unclear audio.
  • Length (minutes) - 20-45 minutes is ideal

Video

  • Are there slides? (Indicates some preparation)
  • Are there closed captions?
  • Is the camera stable?

Other measures

  • Did someone recommend this speaker / conference / course?