Do Authors Base Characters on People They Know?

Where do we get new ideas for our stories? Some writers know exactly how the idea for a plot came to mind. There are crime novel writers who read cases in the newspapers or attend court cases which inspire them. I heard a story about a famous author of women's fiction falling out of her chair in a restaurant while trying to catch what the diners at the next table were saying.
Where do I get my ideas? I don't have any set method for doing it. Sometimes it is a phrase I've heard while sitting on the bus, sometimes the idea just comes out of the blue.
I've been house-sitting in the country these past few weeks. I have much more time to read and browse social media than when I am at home, although I can't really explain why that is so. Perhaps it is the quietness that does it. 
Be that as it may, I have done a lot of reading and I came across the term "imposter syndrome" several times. Oddly enough, this helped me with one of my characters in my Christmas novel which I am currently working on. I hasten to add that I do not know anyone suffering from it - the syndrome not the novel - but I do know a lot of people who have to work very hard at their jobs.
I think, on reflection, that all writers put bits of character from people they know into their stories. There are bossy people, stroppy people, really nice people who make you feel inadequate, go-getters, losers. In other words, there is a whole world of people out there, people you know and like and people who make you pick up your coat and make a run for it. They all make up that fascinating patchwork quilt known as humankind. And that is grist to a writer's mill.