This article in Aesthetics for Birds has some interesting statistics on the percentage of papers authored or co-authored by women and minorities in the top print aesthetics journals: Journal of Aesthetics and Art Criticism and British Journal of Aesthetics. About 20% of articles in these journals are written by women in the period from 2010 onwards. When we look at memberships of professional aesthetics organizations, the percentage of female aestheticians is about 32%. So that means women are underrepresented in JAAC and BJA. What can account for this disparity? JAAC keeps a record of gender and geographic location of submissions.
Sherri Irvin finds "It is notable that over the past three years, women authors have submitted to JAAC at a rate substantially higher than the rate at which they are published in JAAC from 2010-2014, and closer to the proportion of women members in the ASA. During 2 of the last 3 years, the acceptance rate for women has been lower than for men. Though the differences seem small (only 2-3 percentage points), another way of putting them is that in 2012-3, men were 21.4% more likely than women to have their manuscripts accepted, while in 2013-4, they were 11.6% more likely." She also writes "US submissions tend to be accepted at a rate slightly over 20%, while submissions from non-English-speaking countries tend to be accepted at far lower rates".
JAAC practices double-anonymous refereeing. I am in the statistics, since I've co-authored an article that was published in JAAC in 2011. My co-author and I were very pleased with thoroughness of our reviewer, who is one of the few experts on the aesthetics of paleolithic art. We could guess who he was, and it turned out (as he later communicated with us) he also had an inkling as to who we were. Aesthetics is a small world. The only time I reviewed for JAAC I didn't know who the author was, so I believe I reached a verdict that was unsullied by considerations of the author's identity. But was it? Thoughts about the identity of an author can play a role in one's decision, even if you don't want to, this is after all how implicit bias works.
There are several clues in a text that might elicit implicit biases. For instance, citation practices: in my experience, early-career philosophers tend to be more thorough in their review and citation of sources than more senior people (I'm not aware of statistics on this, though, so it might be a wrong impression). Also, the tone of a mature author is something that is very hard to emulate - as Marcus Arvan writes, it is hard even to convey what it is, but there is something about the writing style of confident, established, native English-speaking authors that reviewers unconsciously pick up on and respond positively to. People who aren't native speakers find it even harder to write in this way. We are more likely to respond positively to an engagingly-written piece, even if the points it makes are rather banal.
The author might give clues about the person they are in other ways. For instance, giving examples about the geographic location of buildings in New York city, or aspects of American culture might signal that the author is American (e.g., using a Pontiac or the MoMa in thought experiments). The author might use breastfeeding or other female gendered examples, indicating they are female. JAAC only had 22.4% female reviewers.
Sherri Irvin's piece revealed that people outside the English-speaking world have a much harder time to get their papers accepted at JAAC [update: the overall acceptance rate of people from non-English speaking countries over 3 years of 3.5%]. This is obviously a big problem. Some journals offer proofing services, and I know people in France and The Netherlands who employ professional proofreaders, but both are in senior positions and can afford it. However, it seems rather harsh to impose such a cost on non-native speakers with small budgets.
So often we can at least hazard a guess as to who the author is, especially if the field is small. And even if we don't, there are so many clues in the style of the piece, citation patterns, examples, that thoughts about the author's identity unwittingly come to mind. In the Philosophers' Cocoon, I recently wrote about my personal reviewing practices, and in point (3) I raise this point: What strategies can we, as reviewers, employ to mitigate implicit biases? Just thinking that considerations about an author's geographic location, etc. could impact one's decision is a start, but I don't think it's enough.