Compare scrooges character at the beginning and at the end of a Christmas carol

At the beginning of the text it is said of Scrooge that

No warmth could warm, no wintry weather chill him. No wind that blew was bitterer than he, no falling snow was more intent upon its purpose, no pelting rain less open to entreaty.

Scrooge is so mean and unpleasant and lacking in compassion for his fellows that even seeing-eye dogs for the blind recognize him and pull their masters away from him. Scrooge likes to be alone because other people irritate him, and he likes the darkness and cold because they are cheaper than sitting warm in the light.
In the end of A Christmas Carol, after the visitations of the three ghosts, Scrooge describes himself, saying:

I am as light as a feather, I am as happy as an angel, I am as merry as a schoolboy. I am as giddy as a drunken man. A merry Christmas to everybody!

He has become generous and caring. He "frisk[s]" around his apartment, laughing heartily. He buys a giant turkey for the Cratchits, and he is generous to the man that he sends to purchase it for him. Scrooge even has trouble shaving because he can't stop dancing around. He gives plenty of money to the men who were collecting for the poor the day before, and he even goes to his nephew's house for Christmas dinner rather than keep to himself.