Haha. You need to get more subjects. Three won't tell much at all.
I'm not sure how you'd measure style exactly, but I see your point. I think it's probably somewhat true. Maybe there's a way to measure articulation, dynamics, or something objective like that. What I've heard is men being more aggressive. Women being more concerned about tone, maybe expression, not making anything stand out too much, but also not having the oomph sometimes.
You might also be testing people's perception of whether they think the performer is male or female here though, not an actual difference in the performance itself.
Still an interesting enough experiment.
You could probably do this online somehow, as long as you trust the people who volunteer to become subjects. There's survey monkey and you're able to post sound clips on here.