1. J

    Time Sample Space and Event

    A telephone call from a certain person is received some time between 7:00 A.M. and 9:10 A.M. every day. Define a sample space for this phenomenon, and describe the event that the call arrives within 15 minutes of the hour. The sample space is straight forward S = {[7, 55/6]}, but the event is...
  2. J

    Drawing Two Coins

    Define a sample space for the experiment of drawing two coins from a purse that contains two quarters, three nickels, one dime, and four pennies. Q - Quarter N - Nickel D - Dime P - Penny S = {QQ, QN, QP, QD, DN, DP, NP, NN, PP} This is the book answer. I am wondering why the sample space did...
  3. J


    The table shows the number of boys and the number of girls in each year group at Springfield Secondary School. There are 500 boys and 500 girls in the school. Year Group Number of boys Number of girls 7 100 100 8 150 50 9 100 100 10 50 150 11 100 100 Total 500 500 Azez took...
  4. J

    Sample Space of a Coin

    (a) What is the sample space of tossing three coins? (b) A coin is tossed 3 times in a succession, and the total number of times heads comes up is noted. What is the sample space? Is the answer for those 2 questions the same?
  5. R

    Samplind Distribution

    Hello everyone, I'm not a native english speaking girl and i need your help because i dont understand this exercice at all: Please help me, at least let me understand better the question. Thank you in advance. (Bow)(Bow)
  6. sepinaz

    Can we model the experiments as a stochastic process and estimate the sample size?

    I have an image with the size `5575x9440` and I'm implementing a modified version of the algorithm used in this paper on it, but because the code performance is low right now, I have divided the image to `52628` submatrices of the size `25x40 (1000 pixels)` and my first experiments show that...
  7. T

    Power analysis for sample size that measures heterogeneity

    Hi I hope someone can help me with this question here. I would like to do a power analysis for sample size, but I am unsure how to approach it because I am measuring heterogeneity in my dataset. Here are the details: I have two different types of cell lines and I am measuring the growth of...
  8. I

    What is the probability that the sample mean will be within 1 hour of the population

    The mean television viewing time for Americans is 15 hours per week (Money, November 2003). Suppose a sample of 60 Americans is taken to further investigate viewing habits. Assume the population standard deviation for weekly viewing time is σ = 4 hours. a. What is the probability that...
  9. A

    Choice of Sample Size for Testing Means

    Here they've made a mistake of using Zα/2 since that will be for a two sided test. This particular question is a one sided test so Zα should have been used. Also they multiplied the population variance by 2. Now, my question is how did they calculate that symbol in the denominator. The symbol...
  10. A

    Sample Size for expensive tests

    How do we calculate sample size? Some homosapiens have poked and grunted an assertion of approximately thirty, without giving reason. That is insufficient justification to present to a board for approval of expensive trials. How then do we measure and assess the merits of sample size? For a...
  11. A

    Choice of sample size for testing means

    Is there a reason why this person altered the original formula by multiplying the population variance by 2?
  12. C

    Sample size needed to create bell curve

    Hello again, My boss has looked at my assessment data for my class of thirty children and is querying the accuracy of my data, because my data, when she plots it on a graph, doesn't form a bell curve, unlike the data submitted by my colleagues. I'd like to argue the point that such a...
  13. P

    Random sample Poisson distribution

    Hello, I was hoping someone could help explain how to do this problem. I am pretty stuck. Thanks! X1....X50 is a random sample with Poisson distribution with lamba = 5. What is P(4.5 <= Xbar <= 5.3)?
  14. M

    binomial sample probability

    Twenty-percent of the residents of Boston were born outside of the United States. A random sample of 400 residents is to be selected. Without using the Z table, compute the approximate probability that at least 22% of those in the sample were born outside of the United States. I really don't...
  15. R

    minimum required sample size

    Can I use the following formula in Excel to calculate the required sample size for some A/B testing for various differing groups? a = Base lines response rate b = uplift in base line response rate minimum required sample size = 26*POWER(SQRT(a*(1-a))/(a*b),2) source...
  16. T

    Does changing our expected results change what our sample size should be?

    I had this question from a school assignment, and my thinking is no that what we expect does not change what our sample size would be. I know a larger sample size is best, but , For example 1. If we have a Fair 3 sided dice and expect 1, 2, or 3 to have equal probability of coming out, and we...
  17. D

    Chi square test sample size

    Hello, Does sample size affect the chi square value and Cramer's V? Can someone explain? Thank you!
  18. sakonpure6

    Finding the sample mean

    Hello, I am not sure how to solve for the sample mean in this problem. Would the sample mean of the people who vote for part X be 234/1000 =0.234? That seems too low. Thank you for your time.
  19. A

    Computing the sample proportion

    I did what It says to compute the sample proportion. Divide the number of success (543) by the sample size (1025). Why is it still wrong?
  20. H

    Find the Sample Size

    Roll two fair dice. Each die has six faces. • Let A be the event that either a 3 or 4 is rolled first, followed by an even number. • Let B be the event that the sum of the two rolls is at most 7. The sample size i got is A = [ (3,2), (3,4), (3,6) (4,2) (4,4)...