The document analyzes passages from the short story "The Bet" to characterize the banker. It provides three examples:
1) The banker is described as "younger and more nervous" and "suddenly carried away by excitement", directly characterizing him as impulsive.
2) The banker is directly characterized as "spoilt and frivolous", indicating he sees the large sum of money as insignificant due to his wealth.
3) When mocking the young lawyer's willingness to stay in prison, the banker indirectly characterizes himself as dismissive and insincere, requiring the reader to infer his true feelings.