This is stating that "workers who double majored in college have more stable earnings than workers who majored in a single subject, meaning they’re less susceptible to sharp swings in income." I think the world requires increasing specialization in knowledge and cross-/multi-disciplinary skillsets are required to achieve excellence. But for this particular effect from the article (earning stability) I wonder if it's more related to a selection bias.

I believe people who successfully double-major these days are likely to be more reliable at work. With that increasing specialization, if your niche is experiencing a broad downturn it would seem especially difficult to find another role (though obviously when one does open up, there would be less competition for it). Particularly because:

> “They have a wider funnel, a broader set of opportunities to select from, and this seemed to affect their earnings years later,”

My feelings here differ from that OSU professor's. Personally I feel that after about 5-8 years of experience, it gets increasingly difficult to transition your career out of your original niche. For younger employees it certainly opens up the opportunity to change careers to any ~entry-level role related to either of their degrees, but mid-career and senior roles generally want someone with specific experience, and few entry-level roles will consider mid-career candidates with unrelated experience.

So I do wonder if people who get dual degrees are simply the type of worker who are less likely to get laid off in the first place, regardless of whether they're filling a niche role or something that is garden-variety for one of their degrees.