Recent content by grad

Sorry mate but both your solutions are wrong. You can easily prove this if you try to find P(2,5) or P(1,5) or whatever you want... Does anybody know if such a formula even exists?

Thank you for your answer but what exactly is C?

Well, I 've already seen that but I don't understand how these formulas work. Could you explain a little bit more if you can understand them?

Thank you

That's not correct. Let's suppose we toss a coin 3 times (N = 3) and we want a run of exactly 2 heads (L = 2). Then the combinations that include runs of HH are only two: THH and HHT The total combinations are 2N=3=8 So, P(2,3) = 2/8 = 1/4 Your answer gives 2-N= 1/8

What is the probability that a run of exactly L consecutive heads (or tails) appears in N independent tosses of a coin? Please help me with this one... I 've searched everywhere but I can't find a general answer, for example P(L,N) = ...

Thank you!

Var(Sn) = E(Sn2) = E(Z12 + Z22 + Z32 + ... + Zn2) =* E(Z12) + E(Z22) + ... + E(Zn2) = 1 + 1 + ... + 1 (n times) = n *variables are independent and uncorrelated Is this correct then?

Hi, I know that the expectation E(Sn) for a one-dimensional simple random walk is zero. But what about the variance? I read in http://en.wikipedia.org/wiki/Random_walk#One-dimensional_random_walk" that the variance should be E(Sn2) = n. Why is that? Can anyone prove it? Thank you...

MATLAB code: ceil(400.*rand(1,36)) LOL!

Thank you! I later found out that \sqrt[]{a*b}=\sqrt{a}*\sqrt{b} is NOT correct for NON-REAL numbers.

I am sure that it's a stupid question that has allready been answered in the past, but I couldn't find the solution anywhere. Well I want to know why the following attached equality is not true: