Billy is a college graduate and buys technology devices the first day they are available. He does research on his purchases before making them, and is not persuaded by other's opinions about his product choices. Billy likely belongs to the category of in the context of diffusion of innovation.

Billy likely belongs to the category of EARLY ADOPTERS in the context of diffusion of innovation.

Explanation:

Billy could easily be categorized as an innovator except that he researches about the device that he is going to buy. Innovators generally take the risk and try new things, then they figure out if the device was worth it or not. Generally they try new things just for the sake of being new.

Early adopters on the other hand, still purchase new devices quickly, but they tend to analyze their purchase decisions and options. They do no just buy new things because they are new, but try to buy things that they can actually use.

Generally innovators are people that can afford buying useless stuff (high tolerance for product failure), tend to be very young (teenagers or early 20s) and have enough spare money to do so. While early adopters show a more rational buying behavior.