What's the age difference in movies?

In response to my last post about the distribution of ages of actresses and actors, a Reddit user suggested investigating further the age difference between female and male movie stars. In my first simple analysis, I only compared the average ages of both groups in the overall sample. Now, the next step is to check on a movie basis if there is an age difference between the leading actress and her co-star.


First I needed to identify the two leads of each film (2000-2015, with 10,000+ votes) to calculate the age difference. Unfortunately, there is no direct way to get this information from the IMDb dataset. I, therefore, used a quick-and-dirty approve and chose the first actress and actor in the IMDb cast credits as leads. If I did not find both an actress and an actor in the first three entries (in credits order), I removed the whole movie from the sample. With this method, I was able to get the leading actresses and actors of 1,201 movies. Note that they are not necessarily movie couples. I am aware that a manually selected sample would have been better but considering the simplicity of my approach; I think that the results are acceptable for this analysis. Feel free to check it yourself here.


When we look at the box-plot of the age differences, we can see that on average the leading actor is five years older than his female co-star. It also tells us that in approximately 75% of all movies in our sample have an older male lead. Based on this data, the answer to the question from the title is “Yes” even though the age gap might be not as big as expected.

Age Gap Boxplot

Finally, I also created a density plot which summarizes all data points in a nice looking, colorful graph. The area below the gray dashed line stands for all the movies in which the leading actor is older :

Age Gap Plot