How does topic following on Quora work?

When you follow a topic on Quora, your Feed will start to include its activity — new questions and answers. (Note that you aren't guaranteed to see all of their activity in your feed — this depends on the amount of activity from other topics and people you're following. )

You can follow any topic on Quora through a few different ways:

On a computer:

  • Anywhere you see a topic name, for example as you're reading feed or are looking at the topics that a question is tagged with, you can hover over it and see an option to follow it
  • From any topic page, you can click on the green “Follow Topic” button, located just below the topic name and description

On mobile:

  • You can click on topic names, which will take you to a topic page
  • From any topic page, you can tap on the green “Follow Topic” button

How do I add topics to a question on Quora?

There are a couple ways you can add topics to a question:

  • When adding a new question, one of the steps is topic selection. As you go through the process, Quora will suggest topics to add to the question. You can select from these, as well as search for and add other topics.
  • Once a question is added to Quora, you can add topics by going to that question, and clicking on the link that says "Edit Topics." This link is below the list of topics on the left-hand side of the page.

How specific should topics on Quora be?

We're not totally sure exactly what the right answer to this is yet, but here are some things to think about:

The most important thing that topics are used for is distribution.  A good way to decide if it makes sense to add a topic to a question is "Would people who signed up to monitor questions about topic X want to see this question?" Adding a topic to a question causes that question to show up in the home page feed of everyone following that topic (the details of this may change over time, but in general, following a topic is sort of like subscribing to questions associated with that topic.)

There are some other less important considerations that you might want to think about.

– Clarification: Adding topics to a question can help other editors clarify the question text and give good answers. We're still trying to figure out whether a question should be defined entirely by the text of the question or the tuple (question text, question details) or whether topics should be part of the definition of the question.  So, in general, its probably a good idea to add a topic to a question if it helps others understand your question better.

– Expertise and topic-specific bios:  When we show answers that others give, we'll show a topic-specific bio for anyone who has one on a topic associated with the question.  In addition to just showing the topic-specific bio, we'll probably at some point give more weight to answers that come from people who've demonstrated expertise in a given topic area.  So, if you ask a question like Where is the best sushi in Palo Alto?  then it could make sense to add the topic Sushi to the question since, if a famous sushi chef visited Palo Alto and surveyed the restaurants there, he might have an opinion, and if he answered the question, we'd want to take into account that he really knew what he was talking about (with regards to sushi,) and we'd also want to be able to convey that through his topic-specific-bio (ex. "Sushi Chef for 43 years, Owner of Shiro's Sushi in Seattle until 2007, etc.")  So, in that case, a set of topics like Sushi, Palo Alto, CA ,Restaurants in Palo Alto seems reasonable.

Another thing to think about is that it depends on the number of people who are signed up to follow each topic and how deep each topic area is.  For example, if it were early 2005, it might make sense to have just one topic for Facebook (product) because it was just a little website with a few thousand users, but now it makes sense to have different topics for Facebook Platform , the Facebook API , Facebook (company) , etc.  I don't think there's an a priori way to determine what level of specificity makes sense for a given question; it will generally be a good idea to take into account how much attention is focused on the topics that could logically make sense on the question.

In general, it probably makes sense to add a number of topics that encompass a range of specificity and also lean towards adding more topics rather than fewer if you're having trouble deciding.

How does Quora categorize questions? What algorithms do they use?

Right now, we don't automatically add any topics to questions for the most part*.  The main reasons for this are that, since the site is still getting off the ground, we need to build out the set of topics that belong on the site, and also because we think humans can do a better job.

Once we have a critical mass of topics on the site, we'll probably experiment with suggesting topics and maybe even adding them to new questions automatically.

* There are two exceptions to this: (1) If you do add a follow-up question, the follow-up question starts with all the topics of its parent.  (2) If you ask a question from a topic page, then that topic is automatically attached to the question.

How can I follow every topic on Quora?

The Browse page will show recent new topics, but they get bumped frequently.

You could also just clone my topics from my profile page, as I've been following more every day, but you'd have thousands of clicks ahead of you and that's not a responsive solution to your question.  Suggested Topics is similar, but will take longer to use.

I don't know of an automated way of accomplishing what you want.

Keep in mind, once you hit 4k topics, your home feed will become roughly unusable.  It's not advisable to follow every topic, for now.

Also keep in mind, I'm not following all topics because it's impossible to find orphaned topics (those not attached to any questions) in any reasonable way.

H/T Dev Nag for asking me to answer this one.

Should we combine topics when tagging questions?

First, see How specific should topics on Quora be?

We don't have plans for a feature that would automatically compute topic intersections at the moment, so for now, a question should be added to all topics that it reasonably fits under. That means that a question about a merger in Silicon Valley should be added to Silicon Valley, Silicon Valley M&A, and "Mergers and Acquisitions".

Sometimes topics are too general for a question. For example, there's a United States topic. A question about a restaurant in Palo Alto shouldn't be added to the United States topic because it's unlikely that very many of the people following United States would be interested, even though the restaurant is technically in the US.

Should Quora have a topic hierarchy?

I feel that Quora should not have a topic hierarchy.  In every case I've encountered on the web, a database of information that has a topic hierarchy has been overly-complex, opaque, and difficult to browse.

While tree-structures are a tempting way of classifying information for computer scientists, in reality they are often difficult to navigate.  One problem is that it's not always obvious what "branch" of the tree to go down, as the topic a user is looking for may not fit into any of the top-level (or simply higher-level-than-the-known-level-of-specificity) categories.  At that point, the user is unable to determine whether they need to be more broad in their thinking with regards to what they are looking for (i.e. maybe they are classifying it incorrectly in their own minds) or if the specific topic simply doesn't exist in the hierarchy at all.  The problem is that a topic hierarchy demands an assumption of completeness while simultaneously guaranteeing that it is not complete while leaving the user ignorant after any failed search about whether or not their intended target exists in the hierarchy.  This problem is sometimes partially solved with a search function residing parallel to the topic hierarchy, but this solution can fail if the user is searching for a close synonym to a topic that does exist.

I would greatly prefer a solution where topics are linked to "related topics" constantly generated and refined by users, producing a connected-graph "topic cloud."  Over time, this would link topics to synonyms and related topics, and allow for easy browsing/search: users would be able to crawl from one related topic to the next (instead of tree-walking a hierarchy, which is something that only makes sense to computer scientists), and searches that landed on a semantically-neighboring topic would have a higher probability of eventually directing the user to the item they are looking for.  In a hierarchical classification method, semantically-neighboring topics can often be very far away because the tree requires that only one criterion for classification be used, while free-links can be made based on any criteria at all.

I feel that this is a similar question to whether pages on the internet should be classified within a book-like index (as early Yahoo is an example of) versus just linking to each other willy-nilly in a big random cloud of semantic association.

Is it possible to follow topic combinations in Quora?

This is not currently possible. If you follow multiple topics, we'll prioritize questions that match several of them. Alternatively, you can create a new topic that includes the intersection of the two topics. (for example: "Facebook and Foursquare" or "Ultimate Frisbee in Mountain View")