Philosophy. Diversity has many forms. These include, but are not limited to, gender, race and ethnicity, age, geographic location, and mathematical school. The health of mathematics relies on most conferences/seminars/workshops allowing mathematicians with different mathematical perspectives to mingle.
Best practices in considering diversity will deal with all of these at once. Measurable attributes such as gender or age often serve as the "canary in the coal mine" for less obvious forms of insularity that may have an even more immediate negative impact on the mathematics of the conference. For brevity, we will often refer to women below, but the guidelines apply to other underrepresented groups.
- The too long long list. Come up with a list in the usual way, whatever that means in the context of your event. If the list isn't representative of the full diversity of mathematicians, then ask each member of the organising committee to come up with some mathematicians in the underrepresented group(s). The result will be a long and diverse list of suitable invitees. Choose your short list from this long list. You may find this process results in an "over-representation" of the underrepresented group. That is okay.
- Broaden your base. Think more broadly about the field from which you're recruiting: are there mathematicians working in other fields with overlapping interests? Also, young mathematicians are often a good source for finding a diverse group of speakers (with a caveat; see next bullet point)
- Do not always invite the same senior women. Conversely, don't have a list of eighteen senior men and two young women.
- Question reasonable-sounding assumptions. This can over-determine the situation. For example, if you say "we had a pure speaker last year, so they must be applied, and they were from the US last year, so they must be European" then you've cut your pool to a quarter of its original size, which may be less representative.
- Look at the big picture. Look at data for the last N years, or look at conferences your target audience has been to recently, for a one-off event. For example, if for each of the last five years, the keynote speaker for your general audience event was a pure mathematician, then applied mathematicians become one of the underrepresented groups for the "too long list".
- Explicitly reject the "no good women" claim. See the bullet points above for ways of generating lists of suitable women. If the specific suggestions in this document have not been helpful, there are many other resources available, and it is worth searching online for further guidelines and suggestions.
Approved by Council, 10 November 2017