Charles Dickens' classic novella "A Christmas Carol" still resonates because of its central theme that a person can always change, U.S. researchers say. Naomi Wood, a Kansas State University professor of English who specializes in children's and Victorian literature and culture, says "A Christmas Carol," 170 years after it was written, is a compelling story about the Christmas holiday not as a religious observance, but as an aspect of the social contract -- the time when those who "have" experience joy in sharing with those who "have not." "It's also a story of transformation. Scrooge's story offers the possibility that one can change for the better, become a better person and grow a bigger heart," Wood says in a statement. Dan Hoyt, a Kansas State University assistant professor of English who teaches Dickens' work, says "A Christmas Carol" accurately captures sentiments that many people feel around the holidays, and gives a refreshing message amid the commercialism that surrounds Christmas. "Much of Dickens' work, including 'A Christmas Carol,' has comic touches and is intensely sentimental. Just about everyone can appreciate those qualities during the holiday season," Hoyt says. "It champions generosity and compassion, and when Christmas feels commercialized in so many ways, that message is powerful and comforting." Wood says some of the many screen and stage versions of "A Christmas Carol" overlook the social criticism that is a prominent theme in the novella, Wood says. "The story is a feel-good parable about the joys of individual charity, but the book also demands its readers look at the vast economic system that produces 'want' and 'ignorance,' which Dickens personifies as society's hideous and starving children," Wood said. "Dickens wanted his readers to care about the 99 percent, and even more for the 47 percent -- the people who aren't served by the moneyed and privileged 1 percent."