I'm assuming that by "analogies" you mean ways in which Steinbeck's characters resemble the mouse in Robert Burns' poem in having her best-laid plans turn out to be futile. The main analogy would be in the plan of George and Lennie to have their own farm. Then Candy is drawn into their plan and has his hopes destroyed too. Curley's wife wanted to go to Hollywood and get into the pictures, but she ended up a prisoner on an isolated farm, married to a man she hated. Crooks is very much like the wee mousie in Burns' famous poem. So far, his little nest has not been destroyed, but it is insecure because his physical condition and advancing age will eventually lead to his being discharged and evicted. In the meantime that little room off the stable seems very much analogous to the home the mouse has dug for herself and lined with dry grass and filled with food for the winter. I think that makes four "analogies." A fifth would be most of the other men working on the ranch. Slim seems fairly safe because he is highly valued as a skilled worker, but the other bindle stiffs, including George himself, are about as helpless and insignificant as so many little mice. The most they can hope for is a bunk in a big room and some grub. They have no security whatever--and security may be what Steinbeck had chiefly in mind when he wrote that story and The Grapes of Wrath. He believed that society should provide what is generally called a "safety net" for people, so that they wouldn't be devastated by old age or sickness or economic hard times.