Perhaps the biggest data set of all is the collection of actions, choices, and preferences that each person performs throughout the day, which is called his or her data exhaust. Using such data for scientific purposes is called citizen science. This is noisy data in that most of it is irrelevant or even misleading, but there are ways to cull signal.
That’s not my understanding of what citizen science means. I’ve seen it used when non-scientists (“citizens”) help professional scientists. The Wikipedia definition is
projects or ongoing program of scientific work in which individual volunteers or networks of volunteers, many of whom may have no specific scientific training, perform or manage research-related tasks such as observation, measurement or computation
Bird-watching, for example.
My self-experimentation is not citizen science. I am not doing it to help a professional scientist nor as part of a project. I do it to help myself — in contrast to professional science, which is a job. Almost all self-experimentation by professional scientists and doctors has been done as part of their job. So let me coin a term that describes what I do: personal science. Science done to help the person doing it.
I believe personal science will grow enormously, for several reasons: 1. Lower cost. The necessary equipment, such as software, costs less and less. I use R, which is free. 2. Greater income. People can afford more stuff. 3. More leisure time. 4. More is known. The more you know, the more effective your research will be. The more you know the better your choice of treatment, experimental design, and measurement and the better your data analysis. 5. More access to what is known. For example, Dennis Mangan discovered via the internet that niacin had cured restless leg syndrome. 6. Professional scientists unable to solve problems. They are crippled by career considerations, poor training, the need to get another grant, desire to show off (projects are too large and too expensive), and a Veblenian dislike of being useful. As a result, problems that professionals can’t solve are solved by amateurs. The best-known example is the invention of blood-glucose self-monitoring by Richard Bernstein, who was not a doctor when he invented it.