Recent content by Orphen89

I think I understand what you mean - I did what I think you meant (i.e. P(G | "she said it was G") = P(G and "she said it was G") / P("she said it was G").) and I got (.1*.75)/(.1*.75+.25*.9) = 0.25, which does seem a lot more accurate than my previous answer, and after drawing up the table you...

Bump, could someone please check if I have the correct method down?

Okay, I *think* I understand what you're trying to say. Does this mean that P(G | she said it was G) = 0.1 * 0.75 + 0.25 * 0.9 (instead of 0.1)?

Homework Statement A particular brand of cars, say ABC, comes in only two colours, white and grey. Exactly 90% of ABC cars in a particular town are white and 10% are grey. Mrs Z, a witness to a bank robbery, claims to have seen the thieves escaping in an ABC grey car, which taking into...

Ah okay, I think I know what you mean now - I was taking the value for c = 1 as the interval over 0 ≤ x < 1, so I thought I got it wrong. Also, thanks for all the help Dick you've given me this week (you actually helped me out with a PMF question earlier this week as well which I didn't get...

Homework Statement (1 + 2*x exp(−y))dx − (1 + x^2) exp(−y)dy = 0 with y(0) = 0 Show that the equation is exact and hence find the solution of the initial value problem on the interval 0 ≤ x < 1. The Attempt at a Solution For the differential equation, after solving everything with...

Yup, I was meant to write .15+.3 for the second one. Sorry, my class actually hasn't covered cdfs just yet (we've only done pmfs and are learning about binomial and poisson random variables at the moment). Do you know another way to do it with pmfs, or is it irrelevant in this case? Also...

Homework Statement Let X be a random variable with PMF x 0 2 4 5 p(x) 0.15 0.30 0.30 0.25 (The x values above are supposed to match up with the p(x) values) Find P[2 < X < 4], P[X \leq 3] The Attempt at a Solution Okay, I kinda have an idea...

Homework Statement Consider the use of cubic splines to interpolate a set of data. Suppose at some stage in the calculation we arrive at the following spline functions for two consecutive intervals \tilde{f_{0}} = x^{3} + ax^{2} + bx + c over the interval -1 \leq x \leq 1 \tilde{f_{1}} =...

Wow, I think I finally understand how to do it now. Thanks for all the help Random Variable, you managed to explain the probability generating function to me better than my tutor =D

Really? I think you might be right, because I can remember hearing that that was the answer... I originally thought that (using the data), I could create a probability generating function with a/(1-a) - 1/3 - 1/4 - 1/6, with a = x/2 Do you know where I have gone wrong, (or if I even have...

Sorry about that! I forgot about that part - it is pn=1/2^n for n \geq 3. Thanks for all the help Random Variable, I appreciate it (all this Generating Function stuff is going to be on an exam coming up in a few weeks...)

Sorry I just have one more question - does this mean that for p0= 1/3, p1=1/4, p2=1/6 and pn=1/2^n that the probability generating function is equal to -(7x-6)/(4(x-2)) + 1/3 + (1/4)x + (1/6)x^2? Also, if it is incorrect, could someone please show me the correct method? For some reason I'm...

Thanks for the quick reply! I just have two questions: In the second line, is it supposed to be 1/2 or 1? And in the third line, you're basically just subtracting the p0 value from G(x) right? Thanks for the help.

Homework Statement Consider a branching process with branching probabilities given by P0=1/2 and Pj=1/3^{j} for j \geq 1 Find the probability generating function: \sum^{\infty}_{n=0} p_{n}x^{n} The Attempt at a Solution Now, the answer is supposed to be G(x) = (x+3)/(2(3-x)), but I...