Female-led films make more money

[Sturmundcalm]

great to see the data start to provide cold, hard, financial reason for producers/studios starting to prioritise women on screen actually being real human beings rather than the hero's wife/girlfriend/mother

www.theguardian.com/film/2018/dec/12/women-outperform-men-at-the-box-office-study

When they say "female" I wonder what they mean

Let's face it, a film that can't pass the bechdel test probably isn't as good (on average) as one that can. That result should be no surprise.

On the male vs female lead thing, I wonder whether something similar is going on? A crap film with a female lead may be less likely to get made than a male one. I think there are also a certain proportion of reductive, dumb male led action films made every year, in a way that perhaps doesn't have a female led equivalent. Thus having a female lead correlates (at least to some extent) with higher quality.

When they say "female" I wonder what they mean

I think they check the star's bio and see whether it says they like pink. I can't imagine how else you'd know whether someone is a woman :-)

On the male vs female lead thing, I wonder whether something similar is going on? A crap film with a female lead may be less likely to get made than a male one

That is quite likely. Also, if you hire a famous female actor, she likely had to be better to get where she is than a famous male actor.

And of course, there's just not enough films with female leads to fulfill the demand for them, so women are more likely to go see a random film if it has a female lead than if it has a male lead, which also results in it being more sucessful.