Golden-crowned Sparrow

I usually have to go somewhere out of town to see Golden-crowned Sparrows, a winter visitor to Oregon. However, today this one showed up among the Junco's in my yard. In a few months he will be up north again, spending the breeding season somewhere in Alaska or western Canada. The question is: Is this bird an adult wearing the subdued winter plumage, or an immature bird still waiting for his first bright adult head pattern of gold and black?