<p>This ends up being a non-answer, but I figured I would share some analysis I did. For a while I've been concerned that the site's continual progress rests on the shoulders of a relatively few individuals. It is expected that a relatively few contribute a lot, but I felt the balance here was even more perilous than in some of the other sites I marginally participate on. Or put another way, if 5 of the top users depart the site in one fell swoop I worried we would not have a functioning site anymore.</p>

<p>My perceptions seem to be inaccurate though when examining the data - or at least several of the other sites mentioned face the same issues.</p>

<p>Comparing the long tails of several of the sites mentioned here in terms of the proportion of users that answer questions vs. the proportion of all answers we appear to be pretty similar to Physics, GIS, and MathOverflow in terms of the empirical CDF. The Math and Mathematica site have an even greater amount of inequality than we do here, with 20% of the people answering near 95% of the questions. TCS (theoretical computer science) is the most equitable of the sites listed here, and fits Pareto's 80-20 mark. We are closer to 85-20 - although the interesting part of the bend is closer to around 10% of the users answering questions.</p>

<p><img src="https://i.stack.imgur.com/8ek3H.png" alt="enter image description here"></p>

<p>Here is a slightly <a href="https://dl.dropbox.com/s/t2r2ph0abd4dvnd/ECDFChart.html" rel="nofollow noreferrer">larger version of the figure with tool tips</a> (although they don't help very much given the overlap of the lines).</p>

<p>So although I definitely agree attracting more users should be a long-term goal of the site, from this it doesn't appear to me that we have a problematic imbalance <em>of expert users answering questions</em>, at least relative to some of the other sites listed. </p>

<p>Data for this analysis can be found <a href="https://www.dropbox.com/sh/w3a7yg3ryi0bmsd/AACwAD6_t5bpyN6D-aAHYhr3a" rel="nofollow noreferrer">here</a>. I used <a href="http://data.stackexchange.com/stats/query/203684/the-long-tail-of-answers" rel="nofollow noreferrer">this query</a> at the Data Explorer to gather the csv files for the different sites. </p>
