Variance Definition and 357 Threads

Having a lot of trouble with a particular problem in the topic of variance. The problem is: "Suppose you are organizing a game where you charge players $2 to roll two dice and then you pay them the difference in scores. What is the variance in your profit from each game? If you are playing a...

I have trouble understanding operators and observables: Does <A> the average value of an observable and the variance depend on the state of the system? What does it have to do with the Hamiltonian? Thanks!

Suppose you are conducting a hypothesis test to compare two sample means from independent samples, with the variance unknown, but you know it is the same for both populations. Then you use the pooled estimate of the variance given by [ (n1 - 1)s1^2 + (n2-1)s2^2 ] / (n1+n2-2) I was just...

I have just started University and we have been doing t-tests however in our Computer labs we are supposed to do the Levenes Test. I have done the levenes test from our data of males and female heights in our class. i was just wondering what a value of F = 0.001 and Sig. 0.982 would mean. the...

So i need to find the variance of a number of dice rolls. I know that i use the following formula: N ∑ ( X i - µ)2 i = 1 σ2 = --------------- N but i don't know how to use it. I feel really stupid asking this but i am really lost right...

*** PART I. *** THREE QUESTIONS ON "COULOMB'S LAW" The value of the constant "K" in what appears to be the "ORIGINAL" Coulomb's Law depends upon the nature of the medium. [ K = 1/4pi*epsilon ] where epsilon is the "absolute permittivity of the medium". In many modern books, I...

I am having trouble with this question. Let X equal the number of flips of a fair coin that are required to observe the same face on consecutive flips. (a) Find the p.m.f. of X. if found the p.m.f. to be f(x) = (\frac{1}{2})^{x-1} for x=2,3,4,... (b) Give the values of the mean, variance...