selecting

  1. Y

    Selecting a median curve?

    Interested to see how people would do this... :confused: I have fitted a number of curves to my data sets, and plotted them together. What I want to do is show the 'median curve', as this is a more appropriate 'average' than the mean in this case... They all have the same y-intercept at...
  2. N

    Selecting bag A

    Bag A contains 6 green discs and 4 red discs Bag B contains 3 green discs and 7 red discs I am twice as likely to select a disc from bag A as i am from bag B write down the probability that I will select from bag A? let probability of bag B is P, then 2P + P= 1 m P=1/3 Answer is 2/3 , is...
  3. U

    Help with selecting mathematical readings

    Hi guys, I'm doing a quantitative finance research project (which includes quite a fair bit of probability and statistics) that is based on the following papers: "Systemic Risk and Sovereign Debt in the Euro Area" - Deyan Radev (can be downloaded here: Systemic Risk and Sovereign Debt in the...
  4. J

    Selecting the Sample Size...Please help!

    Suppose you wish to estimate the difference between the mean acidity for rainfalls at two different locations, one in a relatively unpolluted area and the other in an area subject to heavy air pollution. If you wish your estimate to be correct to the nearest 0.1 pH, with probability near 0.90...
  5. M

    Selecting the right Shower Tap for your Bathroom

    A bath room is among the essential parts of any home as it is the area which leads to healthy living. When individuals purchase or create a home, they make sure their bathroom has full functionalities required. The most important feature coming from all is a shower tap. Bath taps function by...
  6. P

    Selecting balls numbered 1 through 4 from an urn

    An urn contains four balls numbered 1 through 4. The balls are selected one at a time without replacement. A match occurs if ball numbered m is the mth ball selected. Let the event Ai denote a match on the ith draw, i = 1,2,3,4. a) Show that P(Ai) = 3!/4! b) Show that P(Ai Intersection Aj) =...
  7. G

    Help for selecting an intraclass correlation

    Dear all, I would like to compute ICCs to estimate the variance in various measures attributable to membership in the 20+ groups in which those measures were administered. However, I'm unclear about which ICC is most appropriate (two-way vs. one-way, mixed vs. random, absolute agreement vs...
  8. X

    Selecting pair of items

    Suppose there are 10 different pairs of socks in a drawer. In other words, there are 20 singleton socks in total in the drawer. I randomly pick 2 socks out from the drawer. What is the probability that the 2 socks that I picked out is a matching pair? My answer to this question is 1/2. But I...
  9. S

    Selecting balls from a bag.

    i have a bag of 6 black balls and 14 white balls. What is the probability of getting 3 black balls out?
  10. D

    Selecting a team under restriction.

    A team of 11 students is chosen randomly from a class of 40 students for a sports event. In the past two years, 15 of these 40 students have participated in this event at least once. What is the probability of selecting for the team at least 3 but no more than 5 students from the group of 15...
  11. S

    Selecting money from a bag.

    A bag contains 5 ten dollar bills, 7 twenty dollar bills, and 6 fifty dollar bills. What is the probability of drawing. a) either ten or twenty dollar bill? b) either twenty or fifty dollar bill?
  12. F

    Probability of selecting 5 numbers from 1-40, no two being consecutive

    Supposing we select 5 integers at random from 1 to 40 inclusive. How could we find the probability of none of these numbers being consecutive? I know we have 40 choose 5 outcomes total. I'm having trouble figuring out how many ways two or more of the 5 numbers would be consecutive though.
  13. D

    Selecting a matrix for linear combination

    Hello all, I'm having trouble with a homework problem and am looking for some guidance. The problem is as follows: "Over Z3 select a matrix X such that the set of all linear combinations of 1m and X is a 9-element field." (The 3 is Z3 and m in 1m are supposed to be sub-scripted) What I...
  14. S

    please help in selecting the events of probability

    I have the following probability assesment table no.of blemishes-0,1,2,3,4,5 probability-0.34,0.25,0.19,0.11,0.07,0.04 I was trying to select an event A i.e more than 2 blemishes and event B which is 4 or fewer blemishes. means P(A>=2) and P(B<=4) inorder to calculate P(A) & P(B)how...
  15. Z

    Need help selecting learning material

    I'm only eligible for math70(Elementary Algebra) and would like any suggestions on books and the such for getting confident enough to score into math 130(College Level Algebra) if not higher. Any input is very much appreciated.
  16. fardeen_gen

    Number of ways of selecting r letters?

    If out of 3n letters there are n\ As,n\ Bs\ \mbox{and}\ n\ Cs, show that the number of ways of selecting r letters out of these is the same as selecting (3n - r) letters out of them. If n < r < 2n + 1, show that the number of ways of selecting r letters is given by \frac{1}{2}(n + 1)(n + 2) + (r...
  17. R

    selecting independent variables from the general solution

    I have got a general solution for the equation xy'' - y' + 4x^3y = 0, x > 0 by converting to the normal version of the self adjoint form and solving with an auxiliary equation I have y = Acos(2x) + Bsin(2x) It then asks to select two independent solutions and verify the wronskian...
  18. C

    Selecting regression variables

    Hi, I am building a regression model to predict housing price, and so far I have 6 variables in the model, and they are all statistically significant, two of them are as follows: x1 (p=0.000296029) x2 (p=8.4599E-13) Then I added the interaction variable (x1x2) between x1 and x2, and...
  19. K

    What is the probability of selecting

    Three applicants are to be selected at random out of 4 boys and 6 girls. What is the probability of selecting? (i) All girls (ii) All boys (iii) At least one boy.
  20. K

    Probability of selecting the first urn.

    Ok here it goes, One urn contains 3 red and 7 white marbles. A second urn contains 2 red and 8 white marbles. One urn is selected and a ball drawn. The probability of selecting the first urn is 0.4 and the probability of selecting the second is 0.6. If a white ball is drawn, find the...