The latest wrinkle in "implicit" gender bias: Professors who don't say enough nice things about their female students when writing letters of recommendation.

From Inside Higher Education:

“Gender Differences in Recommendation Letters for Postdoctoral Fellowships in Geoscience,” published this week in Nature Geoscience, says women are only about half as likely as men to receive letters containing language that describes them as excellent, rather than just good.

Of course, maybe women are only about half as likely as men to be excellent rather than just good geoscientists.

But that possibility didn't receive much attention from the study's lead author, Kuheli Dutt. Dutt, assistant director for academic affairs and diversity at Columbia University's Lamont-Doherty Earth Observator. Dutt told Inside Higher Ed that geology and other earth sciences are "a very male-dominated field."

Women in the geosciences receive 40 percent of doctoral degrees but hold less than 10 percent of full professorships, according to the study, and there's a significant leak in the faculty pipeline at the postdoctoral level.

Here's how the study worked:

An available institutional database of recommendation letters from 2007-12 (stripped of identifying information) made for a rich data set through which to explore the “question of whether men and women were described differently,” Dutt added. So she and her co-authors — Danielle Pfaff, Ariel Bernstein and Joseph Dillard, all Ph.D. candidates at Columbia Teachers College, along with Caryn Block, professor of psychology and education at the college — got to work.

In all, they analyzed 1,224 recommendation letters from 54 countries, considering overall tone based on descriptive language. Phrases such as “scientific leader,” “brilliant scientist,” “role model” and “trailblazer” could put candidates into an “excellent” category. Lower-key phrases such as “highly intelligent," “very productive” and “very knowledgeable,” in the absence of supporting information, tended to get candidates into the “good” category.

About 21 percent of letters turned out to be “excellent.” But just 15 percent of the 362 letters for female applicants were in that category, compared to 24 percent of the 862 letters for male applicants.

But uh-oh:

The study did not control for qualifications, meaning it’s possible that the men in the sample had stronger qualifications that would lead to more powerful descriptions by letter writers.

Hmmm:

Dutt acknowledged this limitation, but said that given the global nature of the data set, “it is highly unlikely that there is a worldwide systemic deficit in the quality of only the female geoscientists.”

As might be expected, the remedy for this widespread failure on the part of budding female geologists to win the appellation "trailblazer" in a recommendation letter is…reeducation camp for their professors:

Dutt suggested starting with “meaningful dialogues on implicit bias, be it at an institutional level or at a larger level.” To attract the best talent, she said, “we need to address any hidden biases that systemically disadvantage one or more segments of the population. And since postdoctoral years are the early career years for geoscientists, women are potentially disadvantaged right from the beginning of their careers.”

And soon enough, every single woman applying for a postdoc in geology will be labeled a "brilliant scientist.." That will solve the problem!