HOMEWORK:     (click here for comments / solutions to the HW)   

Please spend at least 1 if not 2 hours a night reading the material/looking at the proofs/making sure you can do the algebra. Below is a tentative reading list and homework assignments. It is subject to slight changes depending on the amount of material covered each week. I strongly encourage you to skim the reading before class, so you are familiar with the definitions, concepts, and the statements of the material we'll cover that day.

 

 

Future problems:

Monte Carlo Exercises: (1) write a program to estimate the area of a quarter of the unit circle; (2) let f be a probability distribution with finite mean and variance. Prove there exist a and b such that (i) g(x) = f(x+a) has mean zero and the same standard deviation as f, and (ii) h(x) = g(bx) = f(b(x+a)) has mean 0 and variance 1. This result is important because it normalizes different distributions and makes them more easily comparable. For a nice distribution, you don't really start to see the shape until the third or fourth moment (in general). This feature is responsible for some incredibly universality of behavior (see the Central Limit Theorem in Math 162). Page 375: #3, #8. Page 390: #4, #7, #10, #15, #18, #31.


Extra Credit: (1: 1 point) Prove Newton's result that you may assume all the mass of a sphere of radius 1 with uniform density is concentrated at the center. As the book proves this using potentials, you must prove this by direct integration of the force. (2: 2 points) Assume the force of gravity is given by (GMm/rn-1) er in n-dimensional space. Here er is the unit vector in the r-direction. Thus the magnitude of the force is GMm/rn-1 and it is radial. Prove or disprove: we may assume all the mass of a sphere of radius 1 with uniform density is concentrated at the center (ie, the force this exerts is the same as the force of the sphere).