Feel free to play around with my code, which is available here. Some days - between an unchecked global pandemic, the breakdown of voting rights, widespread police brutality, and whatever else is adding stress to your life - the world feels pretty chaotic. But even amid this apparent chaos, our world contains a lot of predictable structure. This is because we’re surrounded by natural covariance: taller people also have bigger feet, fitter people have a lower heart rate, and being outdoors also means being exposed to more light (and Vitamin D!
All code for these analyses is available here. Imagine that you’re an epidemiologist who’s curious whether people who fall ill with COVID-19 differ from those who don’t along several dimensions that measure their health and demographics. Or, imagine that you’re a cognitive neuroscientist who’s curious whether a particular brain region responds differently to two types of images - for example, large and small objects. In both cases, you might want to use a classification analysis to understand whether the categories (infected vs.