Online reviews are everywhere, whether you're looking for a movie to watch, a hotel to stay in or a new air fryer. Many of us read these reviews carefully, even though we probably know that not all reviews are unbiased — or even real. Now, researchers have found out something interesting about online reviews: women generally rate things higher than men. The researchers looked at more than 1 billion online reviews on five different websites, including Amazon, Google and the movie site IMDb. They found that, on average, women rate things more positively than men, and are more likely to give five-star reviews. The research team then did two smaller studies to find out why this might be. They said women don't actually like things any more or any less than men, but they still generally leave better reviews. In one of those smaller studies, more than 1,100 people were asked to rate art made by artificial intelligence software. They were asked to rate the art privately and then publicly. Privately, there was not much of a difference between male and female ratings. But when participants were asked to write public reviews, women were less likely to post lower ratings, especially when they really didn't like the art. The researchers said women may feel more worried than men about the consequences of writing bad reviews. They added that everyone should be able to write reviews without being worried about the consequences.